How to Update and Troubleshoot Problems with the ProSim737 Avionics Suite

The backbone of the simulator is the avionics suite, and for the simulator to run effectively this software must be reliable, feature rich, and robust. 

There are several avionics suites available to simulate the avionics and functionality of the Boeing 737; Project Magenta, Sim Avionics, and ProSim-AR being the most popular.  I have not mentioned Precision Manuals Development Group (PMDG), as PMDG is marketed as a desktop simulation not used widely in a hardwired simulation.

Many virtual flyers assume, that when they purchase an avionics suite, the software will replicate all the aircraft systems, be compatible with their computer and simulator hardware, and probably not need to be updated. Unfortunately, this is rarely the case.

In this article, I will discuss the following:

  • The ProSim User Interface;

  • The ProSim Version Manager;

  • Various troubleshooting protocols;

  • Other potential problems;

  • Updating the Navigational Database; and,

  • Updating the Flight Model.

Version 3

This article was primarily written for Version 2.30.  ProSim Version 3.00 introduced several new features to the Version Manager which enhance troubleshooting and backing up specific files.  Some of the more important changes have been added into this article.

The Reason and Need for Updates

Technology is rarely static, and developers if they are to encapsulate new technology must provide updates to their products.  This evolution can be likened to a game of ‘leap frog’; as something new is released, developers ‘tweak’ their software to take into account new technology while (hopefully) still maintaining compatibility with legacy systems.   

Another reason for updates is that there is not an avionics suite that completely encapsulates 100% of all systems (and functionality) used in the B737.  A possible close exception is PMDG, but as mentioned earlier, this is a desktop simulation (I am not including Level D/Type 7 simulators).

Each company that produces an avionics suite has a specific method to how its software is installed, maintained, and lastly kept up-to-date with improvements, fixes and software upgrades.  For example, Sim Avionics beta test changes and improvements themselves (or to a select group of individuals) and then release a version update.  This is in contrast to ProSim-AR, who release a beta for client appraisal.  Then, after bugs and shortcomings are rectified, release a final release.

ProSim-AR - frequent updates

The avionics suite developed by ProSim-AR for the Boeing 737 Next Generation is feature rich, easy to install and run, and the software is for the most part very robust.   The company ‘appears’ to be committed to ensuring that their software operates across a wide range of computer hardware, and interfaces with as many mainstream hardware components as possible (for example, CP Flight, SimWorld, Open Cockpits, Flight Deck Solutions, etc.).  In my opinion, the company is very proactive in interfacing with new technology to gain the maximum benefit that new technology brings, which includes increased market share and profitability (for ProSim-AR).

With this in mind, ProSim-AR release updates to their software on a very frequent basis.  

Understanding the Basics of the ProSim737 File Structure

It is important to understand the basics to how the ProSim737 file structure is set out, as this will provide guidance to the best way to install an update, and if a problem occurs, troubleshoot.

The ProSim737 suite contains the following modules, located in a folder of the same name.  

(i)      ProSim737 (main system module);

(ii)     ProSim-CDU;

(iii)    ProSim Audio;

(iv)    ProSim Display;

(v)     ProSim MCP (Version 2.30 only);

(vi)    ProSim Panel; and,

(vii)   ProSim737 Hardware Connector;

NOTE:  In Version 3.00 the ProSim MCP module has been amalgamated into the main ProSim 737 main module.

The folders can be installed to either a server (the computer that has flight simulator installed) or any number of clients (computers networked to the server computer).  Duplicate instances of the same module with the exception of the main system and MCP module, can also be installed.  

When installing duplicate modules (instances) of the same name (for example Captain and First Officer CDU or ProSim Display) to the same computer, do not rename the .exe file.  Rather, create a shortcut to the .exe file and rename the shortcut to a specific name (for example, CDU Capt and CDU F/O).

The ProSim737 folder and MCP folder (Version 2.30 only) must be installed to the server computer for optimal performance.  The other folders can be installed to the server or client computer, either as single or duplicate instances.

The ProSim737 folder contains the main system module and this is the module that interfaces with all other modules.

The folders can be installed anywhere on the computer, however, it’s not recommended to place them in the same folder (ROOT folder) where flight simulator is installed.

Important ProSim737 Files

Each ProSim737 folder contains a configuration (config) file.  The configuration file contains information pertaining to screen position, functionality, IP address, etc.  The most important configuration file is located in the main ProSim737 folder.  This file, amongst the things, holds the information that relates to specific hardware, functionality and button assignments.  All configuration files are named config.xml.

Important files, located in the main ProSim737 folder, are the:

(i)     Companyroutes.xml;

(ii)    Config.xml;

(iii)   ConfigMCP.xml (Version 2.30 only);

(iv)   TransitionAltitudes.xml; and the,

(v)    Cockpitsetup.xml.

The configuration files are important.  These files should be regularly backed up.

Other files that relate to the update process are the updatelog.txt and changelog.txt. The updatelog.txt contains information concerning to the latest update, while the changelog.txt provides a list of changes that has occurred in the various ProSim737 releases.   

Important Points:

  • The most important configuration file is the config.xmlfile located in the main ProSim737 folder.  This file contains all information that relates to configuration, customization, and hardware.  It should be regularly backed up.

  • For optimal performance it's recommended to install the main ProSim and MCP module to the server computer.

  • When installing duplicate modules to the same computer, always create and rename a shortcut to the .exe file.  Do not rename the actual .exe file.

User Interface and Version Manager

The User Interface enables you to customise the avionics suite, configure hardware components, update, and troubleshoot problems.

The interface is straightforward to use and I urge you to become familiar with its tab /page layout and content.  I will discuss some of the troubleshooting features of the interface later in this article.

Included in the interface is a Version Manager that can be used to update the avionics suite.  When connected to the Internet, the Version Manager compares the release date of the currently installed avionics suite to the latest available release. 

The Version Manager enables the avionics suite to be updated from within ProSim737.  It's accessible from the User Interface (help/updates).

The Version Manager has three tabs:  Releases, Add-ons and Pre-releases.

Releases tab will display a list of final ProSim737 releases (along with release information and the date it was available).  To install the latest release, or to roll back to an earlier release, you select the install link in the Actions title.  This will cause the selected release to download and be installed to your computer copying over (and updating) a previous release installed.

Add-ons tab displays various add-ons that ProSim-AR have made available.  An example being the ProSim737 aircraft flight model.

Pre-release tab will display a list of beta releases.  Operation is identical to the releases tab discussed above.

One of the advantages of the Version Manager is that it enables you to quickly update the avionics suite to a beta pre-release, final release, or roll backwards to an earlier release.  It also provides information concerning the beta release (Release Notes tab), in addition to enabling you to monitor respective updates to the 737-flight model (Add-ons tab).

Three methods can be used to update the ProSim737 avionics suite:

(i)     Download the latest release from the ProSim-AR website (standalone requiring installation);

(ii)    Download the latest release from the Version Manager (zip file); or

(iii)   Download and install from the Version Manager a beta pre-release or final release.

There is no preferred method, however, option (iii) is the easiest way.

Version 3.00 Improvements to the Version Manager

In Version 3.00 additional improvements have been made to the Version Manager to aid in troubleshooting and the backing up of important files.

Opening the main ProSim menu and selecting Options (located beneath Connected Hardware) will open a Configuration File Manager & Mapping page.  This page displays the hardware family, type and mapping and whether the hardware is in use or not by ProSim (denoted by the colour).

Highlighting an item (text will change to red) and clicking the mappings section will open an additional table that displays a description of each function and its output port number for that particular interface card.  If you click the mappings table number a page opens displaying what function that card is connected.

Finally, at the bottom of the table are two tabs that enable you to create or restore a backup of the config.xml file (discussed in detail later on). 

A backup of the file is saved to C:\Program Data\ProSim-AR\ProSimB738\Backup\.  The config.xml backup is date named enabling consecutive backups of this file to be made and saved.

Beta Pre-release or Final Release ?

ProSim-AR regularly adds functionality and improvements to their avionics suite via beta pre-releases.  A beta pre-release enables users to test their hardware set-up with a release prior to it being finalised.  As such, beta pre-releases often have bugs, shortfalls and other problems associated with them. 

ProSim-AR have a dedicated web-based forum, and request that beta users provide feedback on a pre-release.  This enables issues to be rectified prior to making available a final release via the Version Manager.

The Updating Process

The ProSim737 Version Manager (if used) is smart enough to replace all files within the ProSim737 folder system, with the exception of configuration files and any file ending in .xml (these files are kept intact). 

However, if a release is downloaded from the ProSim-AR website, or the ZIP file option is used, then it will be necessary to manually insert the configuration files to their respective folders.  

ProSim737 updates in sequence.  This means, that after the software has been downloaded, the main ProSim737 module will be installed and run  first.  Then as each .exe file for each additional module is run, that module will update. 

A pop-up box will display 'updating configuration' as each module updates its content and synchronises with the main ProSim737 folder.  When an update to a module has been completed, the software will generate the updatelog.txt file (as discussed earlier). 

The time taken to update across a network between server and client computers depends upon your network speed; usually less than 30 seconds.  

Although theoretically not required, the Scenery Database (config/database) should be checked to ensure it's path is connected to the correct folder in Flight Simulator.  It also doesn't hurt to rebuild the database.  Rebuilding the Database following an update ensures that the link between the database, ProSim737 and Flight Simulator has not been corrupted.

Important Point:

  • Configuration files are generated in each folder as the .exe for each module is opened (run).

Customising How ProSim737 Updates

There are three ways that the User Interface can be set-up to update the avionics suite:

(i)     Manual updating;

(ii)    Ask before updating; and,

(iii)   Automatic updating.

The method is customised in the User Interface, accessible from the drop down box (config/configuration/updates).  The interface also has a box that an be checked/ticked if you want the interface to monitor when a beta release becomes available; a screen pop-up will be displayed when you open the avionics suite.

Backups and Install from Backup

I recommend keeping a complete copy of each ProSim737 folder from the server and client computer.  By backing up the complete folder, you are also backing up the configuration and other important .xml files.

Theoretically, the Version Manager negates the necessity to maintain a backup of ProSim737 (or the configuration file), as the configuration and other .xml files are maintained intact.  However, by keeping a complete copy of the last ‘working’ release, it’s easy to ‘change out’ between releases (roll back or forward).  

All you need to do is delete the ProSim737 folders from the computer, and then copy/paste the earlier folders to the same locations.  All the files are intact and ProSim737 will load whatever release has been installed.

If you don't want to keep a complete copy of the folders and files, then it's also straightforward to roll back to an earlier release by using the Version Manager. The manager will download the selected release from the ProSim-AR server and install it overwriting the newer release on the computer.

My preference is to keep a complete copy the release and copy/paste if you want to roll back.

Automatic Backup of Config.xml File

The Version Manager has a handy tool automated within the software. It will now examine and compare the config.xml file during the updating process.  If the file is different between the two copies, the Version Manager will create a back-up copy called config-old.xml.

The auto backup provides a second level of protection to this important file.

Version 3.00 introduced the ability to easily backup and restore the config file.  Open the User Interface and select the small arrow (adjacent to options).  This will open a second window that examines what interface cards and hardware ProSim is connected with.  At the bottom of the page there is a command that enables you to save the config file or restore a backed up config file.  The file is saved within the ProSim file structure or you can select a preferred folder.

Important Points:

  • Always make a backup up your configuration (config.xml) files.  The config.xml file is the most important file in ProSim as it records your configuration and various user selected settings.

  • If downloading and installing a fresh copy of a release from the ProSim-AR website, then the configuration files will need to be manually added to each folder (from your backed up files).

  • Updates using the Version Manager replace all files within the ProSim737 folder system, with the exception of configuration files and any file ending in .xml.

  • The Version Manager displays the current release of ProSim737 you have installed.

  • A good idea to backup a copy of all the ProSim737 folders on both server and client computers.  Doing so allows you the option to easily replace a ProSim737 release with an earlier release number.

  • After running any update, the ProSim737 Scenery Database should be rebuilt.

Troubleshooting Updates

This section is not the ‘Holy Grail’ to resolve all problems.  Rather, it’s what should be done prior to requesting help from the ProSim-AR Development Group.  Some of the methods used to troubleshoot are quite simple, yet effective.

Occasionally there may be a problem with an update.  The update may cause one of the module’s .exe files to loop continually (open/close/open/close), or there may be limited functionality, or perhaps the ProSim737 main module will continually crash.

Recommended Initial Troubleshooting Protocols

Before spending valuable time in advanced troubleshooting, I suggest you check/do the following:

(i)     Shutdown all computers and restart;

(ii)    Ensure that all modules within all folders on the server and client computers have been updated to the new release (check the update file in the folder or check the release version number by right clicking the screen display and selecting configuration);

(iii)    Close and open all ProSim737 modules on the server and client computers;

(iv)   Check to ensure that the correct IP address is recorded for each display window opened.  To check this, right click the opened screen and select configuration.  This will open the screen’s user interface.  Check that the correct IP address recorded in the server box;

(v)    Check the version of .Net Framework on your client and server computer (discussed later);

(vii)  Replace the configuration file (config.xml) in the main ProSim737 folder with a copy of your backup configuration file;

(viii)  Delete all ProSim737 folders from your server and client computers and download/install from the ProSim-AR website a fresh copy of ProSim737 (remember to replace the configuration files in the ProSim737 folders to maintain your functionality settings and screen position); and,

(ix)     Open the User Interface (config/configuration) and confirm that the correct simulator (ie: FSUPIC, Sim Connect, MSFS) is listed in the options box.  Also ensure the enable embedded MCP beta is not selected, all installed  I/O modules and software are operational, and the simulator is connected.  Furthermore, check that all appropriate drivers have been selected for the add-on components and software you are using (config/configuration/drivers).

Usually problems are resolved by restarting your computer, reinstalling the config.xml file, or reinstalling ProSim737 from a fresh download.  

On rare occasions, the configuration file in the main ProSim737 module may have become corrupted during the update process (jumbled and altered assignments).  If you suspect a problem with the config.xml file, copy/paste your backup configuration file to the main folder.

Often, the easiest and fastest method to alleviate issues and save considerable time is to DELETE all instances of ProSim737 from the server and client computers and reinstall.  Before doing this make sure you have a backup of any files you may wish to keep (configuration files, etc.). 

Download the latest release of ProSim737 from the ProSim-AR website.  Copy the folders to the same location and add a copy of the respective configuration file to each folder.  Then, download the beta release (if required).

A quick word when trying to detect where a problem may be occurring.  Always test with a minimal or vanilla setup.  By this I mean deactivate on-line weather and winds and do not connect any add-ons other than those installed into the flight simulator platform (P3d, etc).  Test with a minimal setup; if everything is OK, then add the next program and so forth.

Advanced Troubleshooting, Log Files and the Input Debugger

If the above-mentioned ideas have failed, or the problem relates to a switch, toggle or USB disconnection of hardware, then the next option is to use some of the features available in the User Interface.  Namely the: System tabs, Driver tab, Input Debugger, Logging features, and Debug Mode. (config/configuration/main tab/drivers tab).  Let's look at each in turn.

Main Tab

After opening the User Interface, the first tab that is usually seen is the Main tab.  The Main tab displays a list of registered and connected interface cards.  It also displays the add-on software components that are specific to your simulator configuration.  This screen is ‘live’ meaning that as you add or remove a device or interface card from the computer the connection (and list) will be updated.

The main tab is particularly helpful in identifying hardware USB disconnects (Windows USB disconnect ding-dong sound). 

In the case of USB disconnects, note any interface cards that you have connected that are either not displayed in the list, or flash on and off simultaneously with the ‘ding-dong’ sound; this will most likely be the offending card/device.  Often removing and replacing the USB connection will resolve a problem.

If the problem is a connection or functionality problem that relates to an add-on component (for example SimWorld MCP, CP Flight, Flight Deck Solutions, etc.).  Click the + symbol adjacent to the name of the device in the software list. This will expand the selected folder for the item in question.  Components not operating correctly, or not connected will be highlighted in red.

Enlarging on the above.   if you select option under I/O modules (located in the main menu) you are presented with 'storecurrentlistasrequired'.   This is a very handy feature in that it saves, as a profile, the interface cards used. If at anytime the cards connected to ProSim737 do not match this list, the disconnected card/harware will be displayed in red.

Important Point:

  • The list displayed in the Main tab includes all legacy components (for example, interface cards that previously may have been used but are now not connected).  To reflect the most up-to-date items, the configuration file in main ProSim737 folder must be edited.  This post in the ProSim-AR forum explains how to remove these entries: Removing Old Entries in Config File.

Drivers Tab

One of the advantages in using ProSim-AR, is that the developer has pre-installed and checked the connectivity of drivers for several add-on hardware components.  This removes the need to regularly update drivers.

The Drivers tab displays a list of all drivers that can be used with ProSim737.  For an add-on component to function, the driver specific to that component must be selected (checked/ticked/turned on).  If it isn't then the component will fail. 

If you have updated ProSim737 to a newer release, and have not used the Version Manager (manual update from the website), then there is a possibility that the correct drivers for your components have not been selected.

Functionality - Checking Inputs and Outputs (System Tabs and Input Debugger)

There are two ways that the User Interface can be used to check whether the movement of a component (input/output) is being registered by ProSim737 and operating correctly:  the System tabs and the Input Debugger.

System Tabs

The System tabs correlate to various aircraft and simulator systems, and when opened will display a list detailing the functionality of that particular system.

If the switch, toggle or whatever component in question is manipulated, there will be a corresponding indication shown in the Systems tab for that component.

I'm unsure if the System tabs were designed with problem troubleshooting in mind. Nevertheless, the various tabs can provide useful and helpful information and should form part of your troubleshooting system. 

Input Debugger

The Input Debugger (help/input debugger) is very easy to use, and the information it generates in its text box may help determine where a problem may reside.

The first time the Input Debugger is selected, a display window (debugger window) will open showing dozens of entries; the list can be confusing to read.  It's recommended to clear the list to make the debugger easier to use (press the clear list tab). 

With the Input Debugger open, you physically move the component in question (switch, toggle, lever, etc).  As soon as you move the component, you will note that its input, output and other related information is displayed in the debugger window.

The use of the Systems tab and Input Debugger is an ideal way to check that ProSim737 has registered the movement (input/output) of a component.

There is also a MCP debug option located in the config file of the MCP module (Version 2.30).  Opening the debug option in the MCP only displays information concerning the MCP.

Debug Mode

The debug mode is an advanced option that should only be used when requested by the Development Group (config/configuration/main/debug mode).   Some explanation of the mode is needed.

ProSim737 will only generate a crashlog.txt that relates to problems within its own software; it will not generate a crashlog.txt file if the problem is located outside of its software.  In such circumstances, the debug mode can be used to force ProSim737 to generate a crashlog.txt file.  This may aid in troubleshooting.

The debug mode will generate a large volume of entries, which to anyone but a software developer will be  nonsensical.  The generated files should be sent to the Development Group.

A further debug mode is located in the MCP tab (config/configuration/main/MCP).  As the name suggests this debugging tool should only be used when there are problems occurring with the MCP.

Important Points:

  • If the problem you are experiencing does NOT generating a crashlog.txt file (after deleting the file), then the problem is NOT related to the ProSim737 software, but rather to an outside source.

  • The debug mode should ONLY be used to generate the crashlog.txt file, after which it should be turned off.  Furthermore, it should only be used if requested by the Development Group.

Log Files

ProSim737 generates a number of log and crashlog files that can be examined to determine problems.

The two primary files, which are located in the main ProSim module folder are the log-System.txt and crashlog.txt files.

Further log files (log-Display.txt, crashlog,txt, log-Audio.txt, etc) can be found in the various ProSim modules (for example, display folders, CDU folder and audio folder).  Secondary log files can also be generated for LNAV and VNAV using HTP protocols.   Scrutinizing these files can often provide incite to the cause of a problem.

The log files, with time can become quite voluminous.  This is because additional information is added to the log every time ProSim737 is opened.  Often it’s easier to view a file that displays information that relates to the last simulation session. Therefore, when trying to troubleshoot an issue, it's a good idea to delete the log-System.txt and crashlog.txt files; the software will automatically generate both files from scratch when ProSim737 is re-run, and the resultant entries will only record the data from the last simulator session - this makes for easier reading.

Sometimes more detail is required in a log file.  To select more detailed (aka verbose) logging, open the User Interface (config/configuration/main/logging).  In the Main tab, beneath Logging and Updates, there is a drop down box - select either normal or verbose logging. 

It’s recommended, when using the simulator, to leave logging set to normal (unless testing).  The reason for this is because the verbose option will generate a significant increase in the number of entries to the various logs with a subsequent increase in system resources.  

If a crash log file is not generated for some reason, navigate to the Windows Event Viewer.  The Event Viewer may provide further information (Google Event Viewer if you are unsure what this is).

In addition to the primary log files, secondary log files can be used to harvest information pertinent to a specific system; for example, VNAV and LNAV.  These files should only be enlisted when requested from the Development Group. 

LNAV log files can be viewed by opening your web browser and selecting 127.0.0.1:8080/lnav or vnav (you replace the address with your own address).

An additional log, that more or less duplicates the information found in the system-log.txt file can be viewed by accessing the web-based URL (help/web access URL's) - http//10.1.1.6 8080/log.  A shortcut to this can be found under the help tab in the ProSim User Interface window.  Web-based URL's were used in earlier versions of ProSim

Important Points:

  • ProSim737 will generate a new log-System.txt and crashlog.txt file if either of the files are deleted. 

  • Whenever posting to the ProSim-AR forum a question concerning a problem, its a very good idea to attach the log-System.txt and crashlog.txt files to the thread.  These files can then be perused by the Development Group.

Other Potential Causes of Problems

The list could be infinite!  However, the following 'potential culprits' seem to regularly cause problems for some users.

Opening Sequence of ProSim737 Modules and Flight Simulator

Sometimes following an update, ProSim737 will crash (drop-out).  If this should occur, there may be an issue with the sequence that the various programs are opened (run).

Theoretically, all the ProSim737 modules should connect automatically with the main ProSim737 module no matter what sequence they are opened. This said, changing the sequence that the ProSim737 main module is opened can resolve the issue.

Some users have reported that opening P3d/FSX before ProSim737 resolves drop-out issues, while others indicate the opposite.  Likewise, some users report that the main ProSim737 module should be opened prior to opening the other ProSim737 modules.

Whatever the sequence, changing the sequence that programs are opened should form part of your initial troubleshooting regime.

Important Point:

  • Always start of the ProSim737 System module using 'Administrator Rights'.

Windows Power Management Settings

If a USB device disconnect occurs after a period of elapsed time, then the computer’s Power Management Settings should be checked.

The Power Management Settings  enable the computer to turn off a device to save power; this is done following a period of elapsed time, or after a device has not been used for some time (for example, USB devices and display monitors).

Earlier operating systems maintained the settings established in Power Management, however, Windows 10 has a nasty habit of changing the Power Management settings without warning.  Therefore, the first check should be the device manager to check that the settings are as they should be.  

In the Device Manager dialog box, expand the Universal Serial Bus controllers tab, right-click each USB Root Hub, and click Properties. In the USB Root Hub Properties dialog box, click the Power Management tab.  The setting that allows the computer to turn off the device must be turned OFF (do not tick/check).

Additionally, check the Power and Sleep options. Depending on the operating system used, there may also be other tabs associated with power options.  Search Advanced Power Settings/USB/ and suspend/disable power management or sleep function.

USB Disconnects and Other Hardware Issues

The list is almost infinite.  However, for those using a number of interface cards and relays, a potential problem can be located with the USB cable, cleanliness and tightness of USB connections (including any USB hub), and loose wiring (especially if connectors have been used).

Clean the USB connections with a quality cleaner to ensure cleanliness and make sure the USB connectors are tight.  If the connectors need tightening, this can easily be done by pushing the small tabs inward on the female USB connection.

Surprisingly, wires that have been connected to relays by connectors can also work their way loose either from the connector blade on the relay or from the connector themselves.  This is caused by the continually opening and closing of the connected relays (movement and vibration), and by the continual heating and cooling of the wires (which can loosen wires from the connector).

Terrain Database (DEM) Installation

The Terrain Database is a separate folder downloaded from the ProSim-AR website.  The data when downloaded is in a zip file which when uncompressed should install the terrain data to a folder called DEM located at:  C:/Program Data/ProSim-AR/

Sometimes the installer doesn't function correctly.  If this happens, uncompress the files to your computer's desktop (or wherever) and copy the folder called DEM (and its files) to the location above.  When done correctly you should have folder called DEM in C:/Program Data/Prosim-AR/DEM

Once the files are installed, run the ProSim737 main module (.exe file) and enter the menu at the top of the User Interface.  Select CONFIG and rebuild the database.  The User Interface should have displayed 'Terrain Database Available'.

The information from the terrain database is recorded in the logdbbuild.txt file located in the main ProSim module folder.

Navigraph Data Installation

Navigraph is the navigation database used by ProSim737.  It is a purchased separately to ProSim. 

The correct navigation database (at time of writing) to download from the Navigraph website is ProSim737 2.24b1 (and above).

Navigraph have an installer (FMS Data Manager) which a standalone program that is free to use.  When setup correctly, the installer will download, uncompress, and install the Navigraph files to the correct folder structure on yuor computer.

Once the database is installed or updated, the ProSim737 main module (.exe file) must be run, and the database rebuilt (User Interface - select CONFIG and rebuild the database).   The database AIRAC cycle number will be displayed in the User Interface.

If the database does not update, there is a possibility that either that downloaded file is corrupt, or more than likely the database has been installed to the incorrect folder structure.

In this case, uncompress the downloaded files to your computer desktop (or anywhere) and copy the database to C:/Program Data/Prosim-AR/Navdata.  

Important Point:

  • Whenever you install the Navigraph database, rebuild the database and check the AIRAC cycle.

.Net Framework

Without going into detail, .Net Framework (pronounced Dot Net) is a language that is designed to bridge other computer languages so that they can be understood.  .Net Framework is designed and written by Micro$oft, and ProSim-AR have used it in newer releases of ProSim737.  

.Net Framework must be installed to all client and server computers.

Windows 10 Updates

Windows 10 has a feature that automatically updates essential files (as determined by Micro$oft) when the computer is connected to the Internet.  Often, the user is unaware that the files have been updated, as the update occurs in the background.

Sometimes a problem will occur when a Windows update deselects features in ProSim737 that are required.  For example drivers.

The Windows 10 updating feature can be deactivated if you use Windows 10 Professional, however, it cannot be deactivated in the Home edition (without registry hacking and other work-arounds). 

Batch Files and Shortcuts

It’s common for individuals to use a batch file to open ProSim737, or at the very least to use a shortcut to the original .exe file within a specific folder.  It’s also commonplace to rename the .exe file to something meaningful other than ProSim Display (of which there are several instances).  

DO NOT rename the original .exe file.  Rather make a shortcut to the file (right click and make shortcut) and rename this file.  If you do rename the original .exe file, the Version Manager will not replace the renamed .exe file and the release update will fail.

Hardware/Mapping

The config.xml file contains the information needed for ProSim to connect with whatever hardware you are using.  Often this hardware changes as items become obsolete and are replaced - for example, interface cards may be updated.  The Hardware/Mappings section of the config file will not these changes.  Rather, it will add new hardware mappings to the list.

To clean up the mappings section, it is necessary to open the config.xml file in a text editor and delete all entries between the <Hardware> section headers.  When the ProSim main menu is opened, a new hardware/mappings section will be generated that includes only the current hardware connected.

ProSim737 Flight Model

ProSim737 has a dedicated flight model for P3D and MSFS-2020.

The flight model has a built in installer which makes the process of installing straightforward - providing you follow the instructions as written by the developer in the opening screen.  The flight model is installed to the main P3D folder or to the community folder if using MSFS-2020.  If using the later, the flight model can be installed to a generic folder outside of the community folder and then linked to the community folder.

Prior to installing a new flight model, it is recommended to uninstall the earlier flight model.  This can be done by using the add/remove program options in Windows or by opening the uninstaller program that comes with the flight model.  Whichever option is selected, you must understand that the installation of the newer flight model will replace any existing files that relate to the model.

The files that are affected are those that reside in the aircraft folder.  The below folder is the location of the folder in my computer running MSFS-2020.  Your location will be different, however, the bolded entry is generic for all users.

D:\\Flight Simulator\MSFS2020Community Folder\Aircraft\prosim-B738-v2023\SimObjects\Airplanes\prosim-b738-2023.

Installation of a new flight model will replace any altered files, additional sound files, and added aircraft liveries with default files.  I strongly recommend that you backup the aircraft folder prior to updating the flight model.  After the new flight model is installed, you can then change-out any files that you want from the previous model.

Important Point:

Always backup the aircraft folder.  Uninstalling or installing a new flight model will delete and replace any files within the aircraft folder with default files.

Dedicated Forum and Requesting Help

ProSim-AR has a dedicated forum that is actively monitored by the Development Group. 

If unable to resolve your issue, the log.txt and crashlog.txt files can be posted to the forum along with a detailed subject line and description of the problem.  In most cases, the Development Group rectify problems quickly.  Failing this, you can submit a support ticket via the ProSim-AR website.

Important Points:

  • I cannot emphasis the importance of a detailed subject line.  It's counter intuitive to think that someone will open a thread that says "Help Me" or "Problem PS Doesn't Work" as opposed to "Marker Sound Not Working With PS Audio", or "MCP Disconnects when Opening ProSim".

  • When your issue has been resolved, open the thread and write RESOLVED in the title line.  This will stop forum members from opening your post to offer help, when in fact the problem is solved.

Disclaimer

The above mentioned information is valid as at the time of writing with Release Version 2.28b3.  However, ProSim-AR frequently update their software, and a future update may change what I have documented.

Final Call

The procedure to update the ProSim737 avionics suite is relatively straightforward, and the updating process streamlined and effective.   Nevertheless, the avionics suite is a complex piece of software and problems can occur following an update.  

The User Interface and Version Manager are powerful tools that can be used to customize the way that ProSim737 is updated and configured, and be used to troubleshoot problems.  Additionally, highly detailed logs can be generated which can be used by the Development Group to aid in rectifying problems.  This said, often the easiest solution to resolve a problem is to reinstall ProSim737 to its virgin state (from the ProSim-AR website), and reinstall your backed up configuration files.

This article has dealt primarily with updating and some of the potential problems that may develop; troubleshooting has only been briefly addressed.  Despite this, the above-mentioned recommendations should rectify most of the problems that may present when updating the avionics suite.

Acronyms and Glossary

  • Development Group - ProSim737 Development Group (software developer).

  • Level D/Type 7 Simulation - Full flight simulator (FFS) is a term used by national (civil) aviation authorities (NAA) for a high technical level of flight simulator. ... A Level D/Type 7 simulator simulates all aircraft systems that are accessible from the flight deck and are critical to training.

  • Manipulate - A term to mean move.  It could be a switch, toggle, button, lever or anything else that can be physically moved.

  • Run - Term meaning to run or open a program.

  • User Interface - The User Interface used to access the customizable features of ProSim737.  The User Interface is accessible by clicking the ProSim737 icon.

  • Version Manager – ProSim737 user interface used to configure and customise the ProSim737 avionics suite.

Update

  • Updated 11 April 2020

  • Updated 19 March 2023 (amended to include important changes made to the Version Manager in Version 3)

Correcting Lag in ProSim737 Weather Radar

This short article relates only to the ProSim737 avionics suite.

The software that controls the avionics suite enables many features to be displayed on the Primary Flight Display (PFD) and Navigation Display (ND), and it's paramount that the PFD and ND display the best possible rendentation of the avionics that is possible.  Anything less will detract from the simulation experience.

ProSim-AR (the developers of ProSim737) are constantly updating their software to facilitate new features, functionality, and improve on existing functionality within the avionics suite.

One area of improvement recently implimented has been the detail that the terrain and weather (from the weather radar) is displayed on the ND.  

Performance Issue

Although the improvement is welcomed, many enthusiasts have reported performance issues when the terrain, or more specifically, the weather radar is displayed.  The condition usually becomes worse when other functionality, such as waypoints, airports, stations, and data are also selected on the EFIS to display on the ND (in addition to terrain and weather radar).  

The performance spike presents as a stuuter, lag, or pause, and this becomes more evident when the aircraft is climbing or banking; the altitude tape in the PFD stutters, as does the compass rose as it moves to a new course heading.

Attempting to Resolve Lag

ProSim-AR have attempted to resolve the issue of lagging, by releasing an alterative method to how the software interprets and displays the data (Direct2D).  Although the use of Direct2D has been ‘more or less’ resolved the display lag or stutter, other problems have surfaced such as the positioning and clarity of the displayed fonts.

It’s important to realize that the lagging issue is not a direct result from a low performance computer or graphics card.  Although using a high-end computer and graphics card will help to provide the necessary ‘grunt’ to display the data without any lagging.

Possible Solution to Lag

On my simulator set-up, I was using one computer monitor and one instance of ProSim737 (ProSim Display) to display the data on the PFD and ND.  Using this combination, my set-up always exhibited lagging and stuttering.  

Recently, I decided to run one instance of ProSim Display for the PFD and another for the ND, while displaying both the PFD and ND on the same computer monitor.  In other words, I separated the resources that are used to display the PFD and ND.

I was surprised that this combination resolved the lagging problem.  I can now operate the ND with waypoints, airports, stations and data, and change between the weather and terrain display without any major lagging being evident on the altitude tape of the PFD or ND compass rose (assuming the aircraft is climbing and/or banking).

Configuration

Setting up the two instances of ProSim Display to feed directly to one computer screen is straightforward.  However, configuring the position of the PFD and ND so that they are adjacent to each other and can be seen simultaneously can be ‘tricky’.  It does take a little bit of time to set up.

Prior to changing anything, always make a back-up copy of your config file.  This file, amongst other things, contains the last position of your various displays on the computer monitor.  The config file is located with the ProSim Display folder.

Excess Data Display

The ND will often display the words 'Excess Data'.  This message indicates that the ND is not capable of displaying all information.  If you deselect an ND option on the EFIS, the display will usually extinguish.  The display also appears on the the ND in the real aircraft.

The message can be disabled in the ProSim737 Instructor Station.

Final Call and Disclaimer

This simple procedure resolved the issue of display lagging on my simulator, however your ‘mileage’ may differ.  Each computer is unique.

If it doesn’t work, then delete the config file and replace it with the backed-up copy.  This will revert the position of the displays to your earlier set-up.  

At the time of writing this article, I was using ProSim737 Version 219b10 with Lockheed Martin P3d Version 4.4 and 4.5.

Repair Backlighting on Throttle Quadrant

The rear of the First Officer side trim lightplate showing one of the two terminals that the wiring loom connects to

During a recent flight, I noticed that the bulbs that illuminate the backlighting for the trim and flaps lightplate (First Officer side) had failed, however, the backlighting on the Captain-side trim lightplate was illuminated.  My first thought was that the 5 volt bulbs that are integrated into the lightplate had burned out; after all, everything has an end life.

Backlighting - Wiring Loom

The wiring loom that supplies the power for the backlighting enters the throttle quadrant via the front firewall, and initially connects with the trim lightplate and parking brake release light on the Captain-side.  A Y-junction bifurcates the wire loom from the Captain-side to the First Officer side of the quadrant, before it snakes its way along the inside edge of the quadrant firewall to connect with the First Officer side trim lightplate, and then the flaps lightplate.  The wiring loom is attached securely to the inside edge of the throttle casing by screwed cable clamps.

The backlighting for all lightplates is powered by 5 volts and the backlighting on the throttle quadrant is turned on/off/dimmed by the pedestal lighting dimmer knob located on the center pedestal. 

Finding the Problem

Ascertaining whether the bulbs are burned out is uncomplicated, however, assessing the terminals on the rear of each lightplate, and the wiring loom the connects to the lightplates, does involve dismantling part of the throttle quadrant.

The upper section of the throttle quadrant must be dismantled (trim wheels, upper and side panels, and the saw tooth flaps arc).  This enables the inside of throttle quadrant to be inspected more easily with the aid of a torch (lamp/flashlight).  When removing the trim wheels, be especially vigilant not to accidently pull the spline shaft from its mount, as doing so will cause several cogs to fall out of position causing the trim mechanism to be inoperable.

After the lightplates have been removed, but still connected to the wiring loom, a multimeter is used to read the voltage of each respective terminal on the lightplate. If the mutlimeter indicates there is power to the terminals, then the bulbs should illuminate. 

What surprised me when this was done, was that the bulbs worked perfectly. Therefore, it was clear the problem was not bulb, but wire related.

Process of Elimination

The process of elimination is the easiest method to solve problems that may develop in complicated systems.  By reducing the components to their simplest form, a solution can readily be attained.

Alligator wire connects power from Captain-side lightplate to the First Officer lightplate.  Note the frayed outer layer of the white aircraft wire.  The gold colour is a thin layer of gold that acts as a fire retardant should the wiring overheat

If you suspect that the wiring is the problem, and don't have a multi meter, then a quick and fool safe method is to connect an alligator cable from the positive terminal of the Captain-side lightplate to the respective terminal on the First Officer lightplate.  Doing this removes that portion of the wiring harness from the circuit. 

In this scenario, the  bulbs illuminated on both trim lightplates.  As such, the problem was not bulb related, but was associated with the wiring loom.

It must be remembered that the wire used to connect the backlighting in the throttle quadrant is OEM wire.  As such, the age of the wire is the same age as the throttle quadrant.  

Inspecting the wire loom, I noticed that one of the wires that connected to the terminal of the lightplate was severed (cut in two).   I also noted that the original aircraft wires had begun to shed their protective insulation layer. 

Aircraft Wire and Insulation Layers

The high voltage and amperages that travel through aircraft wire can generate considerable heat.  This is why aircraft wire is made to very exacting standards and incorporates several layers of insulation that surround the stranded stainless steel wire.  The use of high-grade stainless steel also provides good strength and resistance to corrosion and oxidation at elevated temperatures.  

The green wire has been severed.  A possible scenario was that the wiring loom had been pulled slightly loose from the throttle chassis, and had become caught in the flaps mechanism.  When the flaps lever is moved, the mechanism can easily crimp (and eventually sever) any wire in its path.  If you observe the white wire you can see the insulation that is shedding

Interestingly, one of the insulating layers is comprised of gold (Au).  The gold acts as an effective fire retardant should the wires overheat.

The breakdown of the upper insulating layer is not a major cause for concern, as a 'shedding' wire still has enough insulation to not arc or short circuit.  However, the wire should be replaced if more than one layer is compromised, or the stainless threads of the wire are visible.

Possible Scenario

When inspecting the wiring loom, I noted that one of the screws that holds the cable clamp to the inside of the throttle casing was loose.  This resulted in part of the wire loom to 'hang' near the flaps arc mechanism.    It is possible that during the throttle’s operational use, the movement and vibration of the aircraft had caused the screw to become loose resulting in the wires hanging down further than normal.  It appears that the wire had been severed, because it became caught in the mechanism of the flaps lever.  

Unlike reproduction throttles, the parts used in an OEM throttle are heavy duty and very solid; they are designed to withstand considerable abuse.  The speedbrake lever, when activated can easily cut a pencil in two, and the repeated movement of the flaps lever, when moved quickly between the teeth of the flaps arc, can easily crimp or flatten a wire.

Rather than try to solder the wires together (soldering stainless wire is difficult) and possibly have the same issue re-occur, I routed the wires from both lightplates (trim and flaps) directly to the 5 volt bus bar located in the center pedestal. 

I could have removed the wire loom completely and replaced it with another loom, however, this would involve having to disassemble the complete upper structure of the throttle quadrant to access the wire loom attachment points on the inside of the throttle casing; something I was not keen to do.

Final Call

OEM parts, although used in a static and simulated environment can have drawbacks.  Apart from age, the repeated movement of mechanical parts and the vibration of the spinning trim wheels, can loosen screws and nuts that otherwise should be securely tightened. 

Acronyms

  • OEM – Original Equipment Manufacturer

  • Wire Loom – Several wires bundled together and attached to a fixed point by some type of clamp

Using OEM Panels in the MIP

OEM Captain-side DU panel.  Note the thick engraving and specialist DZUS fasteners

The introduction of the Boeing 737 Max has meant that many carriers are updating their fleets and retiring earlier production 737 NG airframes.  This has flow on benefits for flight simulator enthusiasts, because more and more OEM NG parts are becoming available due to NG airframes being stripped down and recycled.  

Although some items, such as high-end avionics are priced outside the realm of the average individual, many other parts have become reasonably priced and are often a similar price to the equivalent reproduction part.

This article primarily relates to the panels used in the Main Instrument Panel (MIP), and lower kick stand.  The term panel means the aluminum plate that is secured to the framework of the MIP, and lightplate refers to the engraved plate that is secured to the panel.

Do You Notice The Difference

This is a common question.  The resounding answer is yes – the difference between OEM and reproduction parts can be noticed, especially if you compare the identical parts side by side.  This said, some high-end companies manufacturer panels that are almost indiscernible from the OEM panel.  These panels are bespoke, expensive, and usually are only made to a custom order.  Therefore, it really depends on which manufacturer/company you are comparing the OEM panel against.

Close up detail of OEM lightplate and general purpose knobs

By far the biggest difference between an OEM and reproduction panel, other than appearance, is the tactile feel of a knob, the overall robustness of the panel, and the firmness felt when rotating a commercial-grade switch; the later feels very accurate in its movement. 

There is litle compromise with backlighting as an OEM panel has a consistent colour temperature and intensity without hot and cold spots.  

Using a real panel helps to provide immersion and, as your're using a real aircraft part there is no second-guessing whether the panel is an accurate copy; using an OEM panel is literally 'as real as it gets'.  Furthermore, it’s  environmentally friendly to use second hand parts.  New parts (reproduction or otherwise) are made from  finite resources. 

Limitation

Not every OEM part can work in a home simulator.  For example, the OEM potentiometer responsible for the dimming function in the lower kickstand DU panels cannot be used.  This is because Boeing use a rheostat instead of a potentiometer.  Without going into detail, a rheostat is designed to take into account 115 volts AC commonly used in aircraft.  If using these panels. you will need to change the rheostat to a high-end commercial potentiometer.  

Table 1 outlines 'some' of the main differences between the OEM panels and their reproduction equivalents.

Table 1:  Main differences between OEM and reproduction panels (MIP only).

The information presented in the above table, should not be taken in a way that reflects poorly on the manufacturer of reproduction panels.  There are a few high-end companies whose panels are indiscernible from the real item; it’s the purchaser’s knowledge and the manufacturer’s skill that will define whether a reproduction panel replicates the real item.  ‘Caveat Emptor’should always be at the forefront of any purchase decision.

Potential Problems Using OEM Panels in the MIP

Potential problems often surface when attempting to mate OEM parts to the framework of the MIP.  This is because reproduction MIPs rarely echo the identical dimensions of their OEM counterpart. 

OEM Stand-by instrument panel. Although difficult to see from a picture, the overall robustness of this panel surpasses all but the very best reproductions

It's not possible to document every potential problem, as all reproduction MIPs are slightly different to each other.  However, some issues encountered may be the misalignment of screw holes between the MIP framework and the OEM panel, the inability to use the panel's DZUS fasteners, the panel being too large or too small for the MIP in question, or the open framework structure at the rear of the panel (which incorporates the wiring lume and Canon plugs) interfering with the infrastructure of the reproduction MIP, or the mounting of the computer screens.

In general, OEM panels cannot be mounted to a reproduction MIP without major work being done to the framework of the MIP.   The solution is to use a MIP that has been designed 1:1 with the OEM MIP, or fabricate a MIP in-house to the correct dimensions.

Specifics to the FDS MIP

The MIP used in the simulator is manufactured by Flight Deck Solutions (FDS), and although the MIP is made to a very high quality, the dimensions of the MIP are not 1:1. 

The most problematic issue is that the MIP length is slightly too narrow to enable the OEM panels to be fit correctly to the front of the framework.  For example, the OEM chronograph panel is 1 cm wider than the FDS chronograph panel.  Furthermore, most of the OEM panels (such as the standby instrument, chronograph and landing gear panel) measure 130 mm in height as opposed to the FDS panels that measure 125 mm in height.  This causes problems when trying to line up the bottom of each panel with the bottom of the display bezels. 

The standby instrument panel does fit, however, there is a few centimeters of space between the panel and the adjacent display bezel frame.  In the real aircraft, the display bezel and the edge of the standby instrument panel almost abut one another.  The autobrake panel does fit as do the lower kickstand panels.

FDS use screws to attach their panels to the upper MIP framework, however, OEM panels use DZUS fasteners.  The screw holes on the FDS MIP do not align with the position of the DZUS fasteners in the OEM panel.  The lower MIP panel (kickstand) in the real aircraft also incorporates a DZUS rail to which the panels are attached.  The FDS kickstand does not use a DZUS rail, and screws or reproduction DZUS fasteners are needed to secure the OEM kickstand panels.

The above said, FDS does not state that their MIP is I:1, and when asked will will inform you that OEM panels will not fit their products without considerable fabrication.

DZUS fastener that secures DU panel to the MIP framework

Specialist DZUS Fasteners

The OEM panels used in the upper MIP incorporate into the panel a specialist DZUS fastener.  This fastener is used to tightly secure the panel to the framework of the MIP; screws are not used.  Screws are only used to secure the lightplate to the panel. 

The DZUS fastener is shaped differently to the fasteners used to secure the panels located in the lower kickstand, overhead and center pedestal, and these parts are not interchangeable. 

Reproductions rarely replicate these DZUS fasteners.  However, like many things it's often the small things that make a difference (at least aesthetically).

Rear of OEM Captain-side DU panel.   Note heavy duty rotary switches (Cole & Jaycor brand), neat and sturdy wiring lume, and easy connect Canon plug.  The use of the correct bracket in the panel enables the AFDS unit to fit snugly to the panel.  Note the depth of the external frame which can cause placement issues

Advantages Using OEM Wiring Lume and Canon Plugs

A major plus using any OEM panel is that the part usually includes an expertly-made wiring lume that terminates at Canon plug.    If possible, the original wiring lume should be kept intact and additional wiring should be done from the Canon plug.  It’s very difficult to duplicate the same level of workmanship that Boeing has done in relation to the wiring.  Furthermore, the wire that has been used is high-end aviation grade wire.

OEM landing gear panel. Like any OEM part, the neatness in relation to the wiring is immaculate.  A Canon plug enables the panel to be connected to a lume which then connects with whatever interface card is in use

The Canon plug deserves further mention, as the use of a Canon plug (or any connector for that matter) enables you to easily remove the panel for service work should this be required.  If at all possible, the original Canon plug (and wiring) should be used because it’s neat and tidy and ensures a good connection.  However, if the correct Canon plug cannot be procured then a reproduction plug should be fabricated.  There is nothing worse than having to disconnect wires from an interface card to remove a part.

Configuring an OEM Panel

Configuring an OEM panel to use in flight simulator depends on which panel you are referring to. 

Panels with knobs, toggles and switches are relatively straightforward to interface with a respective interface card (Phidget card, PoKeys card, FDS SYS card or similar).  Determining the pinouts on the Canon plug that control backlighting requires the use of a multimeter, and then connection to a 5 volt power supply.  If the panel includes annunciators (korrys), then these will need to be connected to a 28 volt power supply (using the correct pinouts).

Technology is rarely static, and there are other ways to interface and configure OEM panels.  The ARINC 429 protocol is becomminginceasingly common to use along with specialist interface cards, and these will be discussed in separate articles.

Rear of DU panel showing korry connections and AFDS bracket

The Future

The FDSMIP can, with some work, be modified to mount the OEM panels.  However, an easier option is to find another MIP that has been designed to mount the panels, or fabricate a MIP in-house to OEM dimensions.

Final Call

Aesthetically, nothing beats the use of an OEM panel, and the panels used in the upper MIP and lower kickstand offer little comparison to their reproduction equivalents, with possible exception to bespoke reproductions. By far the biggest challenge is determining the pin-outs for the Canon plug, but once known, configuration using a Phidget or other traditional card is relatively straightforward. 

As straightforward as it may seem, potential problems surface when attempting to mate OEM panels to an existing reproduction MIP.  To resolve these issues, often a replacement MIP is needed that has been made to the identical dimensions of the OEM counterpart.

Additional Information

The following articles may provide further information in relation to using OEM parts.

Acronyms

  • ARINC 429 - Aircraft communication protocol

  • DU - Display Unit

  • Lume - A harness that holds several wires in a neat way

  • OEM - Original Equipment Manufacturer

  • MIP - Main Instrument Panel

Adding Liveries to ProSim737 Flight Model

The livery for the JALTRANSOCEAN Air, which depicts a whale shark is spectacular.  Why would you not want to use liveries when some look like this.  The whale shark inhabits the waters that this particular airline fly to (southern Japan) - © DavE-JetPhotos

Flight simulator enthusiasts enjoy flying the livery of their choice, whether it be a cargo carrier such as FedEX, or a livery from one of the many passenger airlines that fly the Boeing 737 airframe.  

Airlines have unique liveries that identify the carrier.  Often the design is specific to the country or to a particular motif unique to the airlines.  For example, QANTAS depicts a red kangaroo on its tail and Aeroflot always depicts the Russian flag on its tail wing.  Some liveries relate to airline branding, others can be nationalistic (those carrying flags on their tail wings), and others can be just for fun - such as Taiwanese airline's Eva Air 'Hello Kitty' livery.  Wikipedia has an interesting list of airlines that have liveries that relate floral emblems, animals, flags and the like.

Some software companies, for example PMDG, have developed livery add-ons that can be installed by a self-extraditable .exe file;  it’s only a matter of clicking the .exe file and following the prompts, and the information, textures and changes are automatically installed behind the scenes by the software.  

The ProSim737 flight model (developed by ProSim-AR) does not at the time of writing provide a self-executable file for add-on liveries; users must install liveries manually.  Thankfully, the steps to install a livery are generic, and have been more or less the same since FS9 and FSX.

This article will address how to install an aircraft livery to the main aircraft folder for ProSim737 using the ProSim737-800-2018 Professional aircraft using Prepar3D (P3D). 

Important Points:

  • As of March 2020 there are a number of differing ProSim737 flight models, each generating a different folder name and a slightly different naming profile in the aircraft section in the aircraft.cfg file.   I have updated the relevant information in this article to reflect the 2020 Version 155 visual model and Version 2.42 flight model.

  • Liveries used in Version 2 flight and visual models are not compatible with the Version 3 flight and visual model.

For those users who use the ProSim737 Version 2 flight and visual model, the process of installing liveries is similar, however, the ProSim737 folder structure is different.  Also, the older liveries use a different method to create the textures (not PBR).

Back-up

Before proceeding with any amendment to the aircraft folder, make a backup of the ProSim737 aircraft folder BEFORE making changes.  It’s also wise to copy the default aircraft configuration file.  This can easily be done by right-clicking the file and saving as a copy.  The copy can reside in the same folder, as it will have the word ‘copy’ annotated to the file name.

It’s good policy to do this just in case a problem is experienced.   If a problem presents itself, it’s an easy matter of deleting the aircraft folder and replacing it with the original, or replacing the aircraft configuration file.

The Basics

We are interested in three components:  

(i)      The ProSim737 default aircraft folder;

(ii)     The add-on livery texture folder; and,

(iii)    The aircraft configuration file (aircraft.cfg).

Note that the default ProSim737 aircraft is installed via a self-executable file that installs the default 738 aircraft to the correct folder.

File and Folder Structure

The ProSim737 aircraft software installs the aircraft to the following folder: D://Documents/Prepar3D V4 Add Ons/ProSim-AR/Simobjects/Airplanes/ProSim737-800-2018 Professional

Important Points:

  • D:// may differ.  It depends upon what drive you installed ProSim-AR and whatever flight simulator platform you use.

  • The aircraft folder name may be different as this relates to what ProSim-AR call their newer released flight models).

One interesting livery is British Airways (BA).  All BA aircraft depict the Union Jack on their tail.  In the 18th Century, England had colonies throughout the world and it was often stated that ‘the sun never set on the Union Jack’.  With the loss of her colonies the sun definitely now sets on the Union Jack, however, it probably never sets on British Airways as there is always a BA aircraft somewhere in the world.  Screen grab of ProSim737 BA livery. © Matthew Fitzjohn

This folder falls outside the main P3D folder architecture, however, various files are automatically linked to P3D so they aircraft can be flown and seen in the game.  In my setup I have two drives, which is why the Prepar3D folder is located on D Drive rather than C Drive.  Your drive may feature a different drive letter.

Livery Texture Folder

An add-on livery is usually downloaded from the Internet in zip file format.  Once the zip file is extracted, you will see a number of folders and files.  At the very least there will be a texture folder, in which is stored the various bitmaps and images necessary to amend the default aircraft with that livery.   There may also be a thumbnail image of the livery and a ‘read_me’ file.

The ‘read_me’ file is important, as this often will contain the correct edits for the livery that need to be added to the aircraft configuration file.

Non-mipped Images

The developer of the livery may also have included additional folders such as non-mipped images.  Opening this folder will reveal an alternate texture folder.  

Textures developed from non-mipped images are displayed differently by P3D and often provide slightly better detail that standard textures.  This may be advantageous if you often zoom into the aircraft to view close-up detail.  There are many variables that affect the appearance of non-mipped textures, including graphic card settings, computer specifications, and P3D settings.  For most users, the use of non-mipped textures in not necessary.  However, ‘horses for courses’, so test and choose whatever is appropriate to your circumstances.  

Mip-Mapping

Mip mapping can be a confusing topic (the naming itself causing confusion). 

Basically, textures are created using one of two methods which generate textures that have been either mip-mapped or non mip-mapped.

With regard to the ProSim aircraft, the mip-mapped textures will always give you better performance, but less visible detail, whereas non mip-mapped textures will be sharper, crisper but will require more resources from your graphics processing unit (GPU).

Important P3D Settings

If using P3D and wanting to take full advantage of mip mapping (mip-maps), it is important to understand that mip-map textures are defined by the slider settings in P3D. 

The Texture Resolution setting in P3D has the most impact on how mip-map textures are displayed.  The maximum slider value is 4096x4096.  However, if the setting is set to a lower value (for example, 2048x2048), the highest resolution displayed will be that value (2048x2048).  If the aircraft texture us made from bitmaps that are 4096x4096, the 2048 setting will not enable the full resolution of the original bitmap to be seen; you will only see a second-order textures (textures at a lower resolution with less detail).

The same principle relates to the Texture Resolution slider setting that controls the vector-based scenery which simply regulates the largest mip-map to be called and displayed.

Another often forgotten variable, that can impact on both mip-maps and non mip-maps is the overall resolution the screen(s) being used.  A higher resolution screen will always display a better quality image irrespective of the mip-maps used.

Concerning frames rates (FPS).  Mip mapping has very little effect on frame rates.  However, using mip-maps will definitely ease and free up resources on the GPU.  Interestingly, this is in contrast to sceneries which can decrease frame rates considerably dependent upon the mip-mapping that has been used to create the scenery textures.  This is because the mapping affects a large area, whereby the mapping in the aircraft is minimal in comparison.

The Anti-liaising settings (AA settings) used in P3D can also have a marginal affect of how mip and non mip-mapped textures display.

Aircraft Configuration File

The aircraft configuration file is important as it contains, amongst other things, the necessary instructions to display whatever aircraft has been selected from the P3D aircraft list.  

The configuration file is set out logically with higher-level entries (top of page) identifying the various liveries that have been included in the main ProSim737 aircraft folder.  By default, the ProSim737 flight model installs a number of liveries to the aircraft folder and automatically amends the entries in the configuration file.

In the example below taken from the aircraft configuration file, the text that relates to the aircraft livery.  Bolded sections need to be edited for each livery.  If using the 2020 Version 3.42 flight model and Verson 1.55 visual model  see entries in blue (different folder naming).

  • [fltsim.XX]

  • title=Prosim_AR_737_800_PRO_2018_Virgin_Australia

  • sim=Prosim738_Pro

  • model=

  • panel=

  • sound=

  • //sound=cockpit

  • texture=VIRGIN

  • atc_heavy=0

  • atc_flight_number=209

  • atc_airline=Velocity

  • atc_model=737-800

  • atc_parking_types=GATE,RAMP

  • atc_parking_codes=VOZ

  • ui_manufacturer="Prosim_AR"

  • ui_createdby="ProSim-AR"

  • ui_type="737-800"

  • ui_variation="PROSIM_AR_Pro_2018_Virgin_Australia"

  • ui_typerole="Commercial Airliner"

  • atc_id=PS209

  • visual_damage=0

----------------------------------------

  • [fltsim.XX]

  • title=ProsimB738 PBR 2020 - Japan Airlines

  • sim=Prosim738_Pro

  • model=

  • panel=

  • sound=

  • texture=Japan Airlines

  • atc_heavy=0

  • atc_flight_number=887

  • atc_airline=ALL NIPPON

  • atc_model=737-800

  • atc_parking_types=GATE,RAMP

  • atc_parking_codes=JAL

  • ui_manufacturer="Prosim_AR"

  • ui_createdby="ProSim-AR"

  • ui_type="737-800"

  • ui_variation="ProsimB738 2020 Japan Airlines Livery"

  • ui_typerole="Commercial Airliner"

  • atc_id=PS209

  • visual_damage=0

Installing Textures to ProSim737 Aircraft

A: Copy the aircraft texture folder for the livery (from the download) and paste the folder into the ProSim737-800-2018 Professional folder located in simobjects/airplanes.

B: Open the aircraft configuration file (for editing). This file is located in the main aircraft folder.  Make sure you back-up this file or copy it BEFORE making changes.  This will enable to you to revert to the original file if a mistake is made.

C: Copy the aircraft details from the downloaded 'read_me' file and add them to the configuration file.  The correct place to add the details is below the last aircraft listed.  If the ‘read_me’ file does not have this information, then it will be necessary to add the information yourself.

By far the easiest method to do this is to copy/paste the last aircraft listing, and then re-name the segments accordingly.  In the example above, I have bolded the sections that need to be edited.

The most important edits are the texture= ?, title= ? and ui_variation= ?. These three entries directly influence whether you will see the livery in the P3D aircraft list and in the game.  It’s very important that the texture= ? be the exact name of the texture file in the aircraft folder; your livery will not be able to be seen if this is not done.  In some instances, the name of the texture folder may be an airline’s name (texture.virgin) or a three letter aircraft code such as texture.ual (United Airlines).  

D: The FLTSIM number also needs to be edited to reflect the correct sequence order in the configuration file. Make sure each aircraft has a sequential number. If you have three aircraft liveries, the files will be [fltsim.01], [fltsim.02], [fltsim.03].  Be especially vigilant to copy all brackets, equal signs and commas (syntax) as these are necessary to see your aircraft in P3D.

Problems and Troubleshooting

By far the easiest way to troubleshoot a problem, such as the aircraft not being visible in the P3D aircraft folder, is to delete the aircraft configuration file and reinstall the original backed up file.  Then redo your work ensuring there are no mistakes.  If your mistakes relate to the actual texture folders, then delete the complete folder and reinstall the original backed up folder and start again.  Most problems relate to typo errors such as forgetting to include the correct syntax (punctuation marks).

Screen capture showing the P3D aircraft selection folder.  Note the ‘show only favourites’ star, which when selected, will cause that livery to be displayed in the list at the expense of liveries not selected by the star.  Also, note the additional identifier in the vehicle type column (737-800 CARGO)

Setting Up the P3D Aircraft Folder for Ease of Use (favourites and type)

When you open P3D to select an aircraft, a graphical user interface (GUI) screen displays  the aircraft and liveries that are installed to the aircraft folder. 

This list can be long and unwieldy to navigate with the mouse, not to mention time consuming - you want to be able to identify your 738 liveries quickly and not wade through several versions of the aircraft you do not use.  To prune the number of aircraft you need to sort through, you can delete the unwanted aircraft from the aircraft folder, however, an easier method is to use the favourite functionality.

Select the favourite star for those aircraft/liveries you want to be see displayed in the aircraft list.   Once an aircraft /livery has been allocated as a favourite, it will always be displayed in the list, while those aircraft not ‘starred’ will not be displayed.  

If you have both cargo and passenger aircraft (or military versions of the B737), you may also want to segregate these aircraft by type.  This makes it easier to find a particular aircraft type.   This can easily be done by editing the title= ? and the ui_type= ? for that aircraft in the aircraft configuration file.  

In the example below the aircraft type has been edited to reflect a cargo aircraft (Aloha Air Cargo).  Editing the title is obvious as this changes the name in the P3D aircraft list.  However, editing the ui_type= ? enables you to change the aircraft type.  In the example below, I have included the word CARGO to differentiate cargo liveries from passenger liveries.  I have bolded the entries that need altering.

  • [fltsim.XX]

  • title=Prosim_AR_737_800_PRO_2018_Aloha_Air_Cargo

  • sim=Prosim738_Pro

  • model=

  • panel=

  • sound=

  • //sound=cockpit

  • texture=AAH

  • atc_heavy=0

  • atc_flight_number=211

  • atc_airline=Aloha

  • atc_model=737-800

  • atc_parking_types=GATE,RAMP

  • atc_parking_codes=AF

  • ui_manufacturer="Prosim_AR 2018"

  • ui_createdby="ProSim-AR"

  • ui_type="737-800 CARGO"

  • ui_variation="PROSIM_AR_Pro_2018_Aloha_Air_Cargo"

  • ui_typerole="Commercial Airliner"

  • atc_id=PS211

  • visual_damage=0

Livery List

Liveries for the Version 3 flight model can be downloaded from the ProSim-AR forum.

I also have a small collection of ProSim737 Version 3 liveries in the file download section.

Final Call

Adding various liveries can be fun and adds a element of realism, especially if you fly in different regions and enjoy looking at the aircraft, or are a videographer that creates flight simulator videos.   Paring down the aircraft list in P3D to display only the aircraft and liveries you want to see, and then segregating aircraft based on type, can save considerable time and mouse use.

The livery for JAL Transocean Air – another viewpoint.  There is also a pink coloured livery.   Japan is one of my favourite regions to fly in.

String Potentiometers - Are They Worthwhile

Custom-made box housing Bourne 3500-3501 rotary potentiometer.  Note cable, dog lead clip, and JR Servo connection wires

A flight simulator enables us to fly a virtual aircraft in an endless number of differing scenarios.  The accuracy of the flight controls, especially when the aircraft is flown manually (hand flown) comes down to how well the aircraft’s flight controls are calibrated, and what type of potentiometer is being used to enable each control surface to be calibrated.

This article will examine the most common potentiometers used.  It will also outline the advantages in using string potentiometers in contrast to inexpensive linear and rotary potentiometers.

What is a Potentiometer

A potentiometer (pot for short) is a small sized electronic component (variable resister) whose resistance can be adjusted manually, either by increasing or decreasing the amount of current flowing in a circuit.

The most important part of the potentiometer is the conductive/resistance layer that is attached (printed) on what is called the phenolic strip. This layer of material, often called a track, is usually made from carbon, but can be made from ceramic, conductive plastic, wire, or a composite material.  

The phenolic strip has two metal ends that connect with the three connectors on the potentiometer.  It’s these connectors that the wires from a control device are soldered to.  The strip has a wiper-style mechanism (called a slider) that slides along the surface of the track and connects with two of the potentiometer’s connectors. 

The strip enables the potentiometer to transport current into the circuit in accordance with the resistance as set by the position of the potentiometer on the phenolic strip. 

As the potentiometer moves from one position to another, the slider moves across the carbon layer printed to the phenolic strip.  The movement alters the current (electrical signal) which is read by the calibration software.

Inexpensive rotary potentiometer.  This pot previously controlled the calibration of the ailerons.  The pot was inserted into the base of the control column (removed for picture) and held in place by the fabricated bracket.  It worked, but accurate calibration was time consuming

Types of Potentiometers (linear, rotary and string)

Potentiometers are used in a number of industries including manufacturing, robotics, aerospace and medical.  Basically, a potentiometer is used whenever the movement of a part needs to be accurately calibrated. 

For the most part, flight simulators use adjustable type potentiometers which, broadly speaking, are either linear or rotational potentiometers.  Both do exactly the same thing, however, they are constructed differently.  Another type of rotary potentiometer is the string potentiometer.

A linear potentiometer (often called a slider) measures changes in variance along the track in a straight line (linear) as the potentiometer's slider moves either in a left or right direction.  A linear potentiometer is more suitable in areas where there is space available to install the potentiometer. 

A rotary potentiometer uses a rotary motion to move the slider around a track that is almost circular. Because the potentiometer's track is circular, the size of a rotary potentiometer can be quite small and does not require a lot of space to install.

A very inexpensive linear potentiometer ($3.00).  The tracks on this pot are made from carbon and the body is open to dust and grime.  They work quite well, but expect their life to be limited once they begin to get dirty

Potentiometer Accuracy

The ability of the potentiometer to accurately read the position of the slider as it moves along the track is vital if the attached control device is to perform in an accurate and repeatable way. 

The performance, accuracy, and how long that accuracy is maintained, is governed by the internal construction of the potentiometer; in particular the material used for the track (carbon, cermet, composite, etc).  Of particular importance, is the coarseness of the signal and the noise generated (electrical interference). when the potentiometer has power running through it.

For example, cermet which is composite of metal and plastic produces a very clean low noise signal, where as carbon often exhibits higher noise characteristics and can generate a course output.  It’s the coarseness of the signal that makes a control device easy or difficult to calibrate.  It also defines how accurately the potentiometer will read any small movement.

Potentiometers that use carbon form the mainstay of the less expensive types, such as those used in the gaming industry, while higher-end applications that requite more exacting accuracy use cermet or other materials. 

Essentially, higher end potentiometers generate less noise and produce a cleaner output that is less course.  This translates to more accurate calibration.  This is seen when you trim the aircraft. 

A quality mid to high-end potentiometer, when calibrated correctly, will enable you to easily trim the aircraft, insofar that the trim conditions can be replicated time and time again (assuming the same flight conditions, aircraft weight, engine output, etc).

Simulators, Dust, Grime and Other Foreign Bodies

Flight simulators to control a number of moving parts, generally use a combination of linear and rotary potentiometers.  For example, a rotary potentiometer may be used to control the flight controls (ailerons, elevator and rudder) while a linear potentiometer may be used to control the movement of the flaps lever, speedbrake and steering tiller. 

Any component that has a current running through it will attract dust, and the location of the potentiometer will often determine how much dust is attracted to the unit.  A potentiometer positioned beneath a platform is likely to attract more dust than one located behind the MIP or enclosed in the throttle quadrant.

A rotary potentiometer is an enclosed unit;  it is impervious to dust, grime and whatever else lurks beneath a flight simulator platform.  In comparison, a linear potentiometer is open to the environment and its carbon track can easily be contaminated.  Once the track has become contaminated, the potentiometer will become difficult to calibrate, and its output will become inaccurate.

Sometime ago, I had a linear potentiometer that was difficult to calibrate, and when calibrated produced spurious outputs.  The potentiometer was positioned beneath the platform adjacent to the rod that links the two control columns.  When I removed the potentiometer, I discovered part of the body of a dead cockroach on the carbon track. 

This is not to say that linear potentiometers do not have a place – they do.  But, if they are to be used in a dusty environment, they must have some type of cover fitted.  A cover will minimise the chance of dust adhering to the potentiometer’s track. 

I use linear potentiometers mounted to the inside of the throttle quadrant to control the flaps and speedbrake.  The two potentiometers are mounted vertically on the quadrant’s sidewall.  This area is relatively clean, and the vertical position of the mounted potentiometers is not conducive to dust accumulation.

Ease of Installation

Both linear and rotary potentiometers are straightforward to install, however, they must be installed relatively close to the item they control.  Often a lever or connecting rod must be fabricated to enable the potentiometer to be connected with the control device.

String Potentiometers (strings)

Cross section diagram showing internals of string potentiometer. Diagram © TE Connectivity.

A string potentiometer (also called a string position transducer) is a rotary potentiometer that has a stainless steel cable connected to a spring-loaded spool. 

The string potentiometer is mounted to a fixed surface and the cable attached to a moveable part (such as a control device).  As the control device moves, the potentiometer produces an electrical signal (by the slider moving across the track) that is proportional to the cable’s extension or velocity.  This signal is then read by the calibration software. 

The advantages of using string potentiometers over a standard-issue rotary potentiometer are many:

(i)        Quick and easy installation;

(ii)       Greater accuracy as you are measuring the linear pull along a cable;

(iii)      Greater flexibility in mounting and positioning relative to the control device;

(iv)      No dust problems as the potentiometer is enclosed;

(v)       No fabrication is needed to connect the potentiometer to the control device (only cable and dog clip) and,

(vi)       Greater time span before calibration is required (compared to a linear potentiometer).

The importance of point (iii) cannot be underestimated.  The string can be extended from the potentiometer within a arc of roughly 60-70 degrees, meaning that the unit can be mounted more or less anywhere.  The only proviso is that the cable must have unimpeded movement. 

Attachment of the string to the control device can be by whatever method you choose.  I have used a small dog lead clip.  As the potentiometer is completely enclosed dust is not an issue, which is a clear advantage in that once the potentiometer calibrated, the calibration does not alter (as dust does not settle on the track).

I have used string potentiometers to calibrate the axis on the ailerons, elevators and rudder (one potentiometer per item), in addition to using  a dual-string potentiometer in the throttle quadrant to calibrate the two thrust levers.  Another single-string potentiometer controls the position of the flaps lever.

Cost

High-end commercial string potentiometers are not inexpensive.  Many are used in the medical industry where extremely tight tolerances must be met at all times.  The more accurate the potentiometer the more the potentiometer will cost.  But you have to look at the end product in use and the level of positional accuracy that's required.  While a high-end potentiometer can definitely be used, the accuracy you are paying for probably won't be needed or used by ProSim-AR.  Put another way, it's like buying a high tensile strength dog lead, when a piece of rope will do the same job.

If you search the Internet, you will find average priced string potentiometers, and these are the ones that will suit your application perfectly.

rotary String potentiometer.  This pot connects to the ailerons.  The stainless cable can be seen leaving the casing that connects with the aileron controls.  An advantage of string pots is that they can installed more or less anywhere, as long as there is unimpeded access for the cable to move

Fabricate Your Own String Potentiometer

As mentioned, whilst you can purchase ready-made string potentiometers, their cost is not inexpensive.  As a trial, a friend and I decided to fabricate our own string potentiometers.

The potentiometers used are manufactured by Bourns (3590S series precision potentiometer).  These units are a sealed, wire-wound potentiometer with a stainless steel shaft.  According to the Bourns specification sheet these potentiometers have a tolerance +-5%. 

Diagram showing spring-loaded spool. Diagram © TE Connectivity.

The potentiometer is mounted in a custom-made acrylic box in which a hole the size of the potentiometer's end, has been drilled into the lid.   Similar boxes can be purchased in pre-cut sizes, but making your own custom-sized box enables the potentiometer to be mounted inside the box in a position most advantageous to your set-up. It also enables you to place the mounting holes on the box in strategic positions.

Another small hole has been drilled in the side of the box to enable the stainless steel cable to move freely (see image at beginning of article).  If you want to allow the cable to move through an arc, this hole must be elongated to enable the cable to extend at an angle and move unimpeded. 

The cable (string) is part of a self-ratcheting spool (also called a retractor clip) which is glued to the inside of the box and connected directly with the stainless steel shaft of the potentiometer.  To stop the shaft of the potentiometer from spinning freely, a hole was drilled into the shaft.  A small screw secures the shaft to the inside the ratchet spool mechanism. 

The cable when attached to a solid point is kept taught by the tension of the self-ratchet spool (an internal spring controls the tension).   Ratchet spools are easily obtainable and come in many sizes and tensions.   Three standard JR servo wires connect the potentiometer to a Leo Bodnar BU0836A 12 bit Joystick Controller card.  A mini dog lead clip is used at attach the cable to the control device.

One of the major advantages when using string potentiometers is that the actual potentiometer does not have to be mounted adjacent to, or even close to the device it controls.  The line of pull on the cable can be anything within roughly a 70 degree arc. 

A string potentiometer that connects to the two thrust levers in the throttle quadrant

Applications

A string potentiometer can be used in the following applications: ailerons, elevators, thrust levers, speedbrake and flaps.  The string potentiometer can also be used for the rudder, however, as the input to the rudder is course, there probably is little advantage in using a string potentiometer in this application - a normal rotary potentiometer is suitable.

By far the most important of the above-mentioned applications are the ailerons, elevators and the thrust levers on the throttle quadrant.

Additional Information

Final Call

Previously, I used inexpensive linear and rotary potentiometers to control the main flight controls.  I was continually plagued with calibration issues, and when calibrated, the calibration was not maintained for more than few months.  Furthermore, manual flight was problematic as the output from each of the  (cheap) potentiometers was very course, which translated to less accuracy when using the ailerons and elevators.  Trimming the aircraft in any condition other than level flight was difficult.

Without doubt, the use of quality string potentiometers have resolved all the earlier calibration and accuracy issues I had been experiencing.  With the replacement potentiometers, the aircraft is easily hand-flown and can be trimmed more accurately.

Perhaps in the future I will ‘up the anti’ and purchase two commercial high-end string potentiometers (or use hall sensors), but for the time being the Bourns potentiometers suit my requirements.

Flight Management System (FMS) Software and its Relationship with LNAV and VNAV

OEM 737 CDU page displaying the U version of software used by the Flight Management Computer.  The page also displays the current NavData version installed in addition to other information

The procedure to takeoff in a Boeing 737 is a relatively straightforward process, however, the use of automation, in particular pitch and roll modes (Lateral and Vertical Navigation), when to engage it, and what to expect once it has been selected, can befuddle new flyers.  

In this article I will explain some of the differences between versions of software used in the Flight Management System (FMS) and how its relates to Lateral and vertical Navigation (LNAV  & VNAV). 

It’s assumed the reader has a relatively good understanding of the use of LNAV and VNAV, how to engage this functionality, and how they can be used together or independently of each other.

FMS Software Versions

There are a several versions of software used in the FMC; which version is installed is dependent upon the airline, and it’s not unusual for airframes to have different versions of software.

The nomenclature for the FMC software is a letter U followed by the version number.  The version of software dictates, amongst other things, the level of automation available.  For the most part, 737 Next Generation airframes will be installed with version U10.6, U10.7 or later.

Boeing released U1 in 1984 and the latest version, used in the 737 Max is U13.

Later versions of FMC software enable greater functionality and a higher level of automation – especially in relation to LNAV and VNAV.

Differences in Simulation Software

The FMS software used by the main avionics suites (Sim Avionics, Project Magenta, PMDG and ProSim-AR) should be identical in functionality if they simulate the same FMS U number.  

As at 2018, ProSim-AR uses U10.8A and Sim Avionics use a hybrid of U10.8, which is primarily U10.8 with some other features taken from U11 and U12.  Precision Manuals Development Group (PMDG) uses U10.8A.  

Therefore, as ProSim-AR and PMDG both use U10.8A, it’s fair to say that everything functional in PMDG should also be operational in ProSim737.  Unfortunately, as of writing, PMDG is the only software that replicates U10.8A with 97+-% success rate.

To check which version is being used by the FMC, press INIT REF/INDEX/IDENT in the CDU.  

Writing about the differences between FMC U version can become confusing.   Therefore, to minimise misunderstanding and increase readability, I have set out the information for VNAV and LNAV using the FMC U number.   

Roll Mode (LNAV)

U10.6 and earlier

(i)    LNAV will not engage below 400 AGL;

(ii)    LNAV cannot be armed prior to takeoff; and,

(iii)    LNAV should only be engaged  when climb is stabilised, but after passing through 400 feet AGL.

U10.7 and later

(i)    If LNAV is selected or armed prior to takeoff, LNAV guidance will become active at 50 feet AGL as long as the active leg in the FMC is within 3 NM and 5 degrees of the runway heading.  

(i)    If the departure procedure or route does not begin at the end of the runway, it’s recommended to use HDG SEL (when above 400 feet AGL) to intercept the desired track for LNAV capture;

(ii)    When an immediate turn after takeoff is necessary, the desired heading should be preset in the MCP prior to takeoff;  and,

(iii)    If the departure procedure is not part of the active flight plan, HDG SEL or VOR LOC should be used until the aircraft is within range of the flight plan track (see (i) above).

Important Point:

•    LNAV (U10.7 and later) can only be armed if the FMC has an active flight plan.

Pitch Mode (VNAV)

U10.7 and earlier

(i)    At Acceleration Height (AH), lower the aircraft’s nose to increase airspeed to flaps UP manoeuvre speed;

(ii)    At Thrust Reduction Altitude (800 - 1500 feet), select or verify that the climb thrust has been set (usually V2+15 or V2+20);

(iii)    Retract flaps as per the Flaps Retraction Schedule (FRS); and,

(iv)    Select VNAV or climb speed in the MCP speed window only after flaps and slats have been retracted.

Important Points:

  • VNAV cannot be armed prior to takeoff.

  • Remember that prior to selecting VNAV, flaps should be retracted, because VNAV does not provide overspeed protection for the leading edge devices when using U10.7 or earlier.

U10.8 and later 

(i)    VNAV can be engaged at anytime because VNAV in U10.8 provides overspeed protection for the leading edge devices;

(ii)    If VNAV is armed prior to takeoff, the Auto Flight Direction System (AFDS) remains in VNAV when the autopilot is engaged.  However, if another pitch mode is selected, the AFDS will remain in that mode;

(iii)    When VNAV is armed prior to takeoff, it will engage automatically at 400 feet.  With VNAV engaged, acceleration and climb out speed is computed by the FMC software and controlled by the AFDS; and,

(iv)    The Flaps should be retracted as per the flaps retraction schedule;

(v)    If VNAV is not armed prior to takeoff, at Acceleration Height set the command speed to the flaps UP manoeuvre speed; and,

(vi)    If VNAV is not armed prior to takeoff, at Acceleration Height set the command speed to the flaps UP manoeuvre speed.

Important Points:

  • VNAV can be armed prior to takeoff or at anytime.

  • At thrust reduction altitude, verify that climb thrust is set at the point selected on the takeoff reference page in the CDU.  If the thrust reference does not change automatically, climb thrust should be manually selected.

  • Although the VNAV profile and acceleration schedule is compatible with most planned departures, it’s prudent to cross check the EICAS display to ensure the display changes from takeoff (TO) to climb or reduced climb (R-CLB).  

Auto Flight Direction System (AFDS) – Operation During Takeoff and Climb

U10.7 and earlier

If the autopilot is engaged prior to the selection of VNAV:

(i)    The AFDS will revert to LVL CHG;

(ii)    The pitch mode displayed on the Flight Mode Annunciator (FMA) will change from TOGA to MCP SPD; and,

(iii)    If a pitch mode other than TOGA is selected after the autopilot is engaged, the AFDS will remain in that mode.

U10.8 and later

(i)    If VAV is armed for takeoff, the AFDS remains in VNAV when the autopilot is engaged; and,   

(ii)    If a pitch mode other than VNAV is selected, the AFDS will remain in that mode.

Preparing for Failure

LNAV and VNAV have their shortcomings, both in the real and simulated environments.

To help counteract any failure, it’s good airmanship to set the heading mode (HDG) on the MCP to indicate the bearing that the aircraft will be flying.  Doing this ensures that, should LNAV fail, the HDG button can be quickly engaged with minimal time delay; thereby, minimising any deviation from the aircraft’s course.

Final Call

I realise that some readers, who only wish to learn the most recent software, will not be interested in much of the content of this article.  Notwithstanding this, I am sure many will have discovered something they may have been forgotten or overlooked.

The content of this short article came out of a discussion on a pilot’s forum.  If there is doubt, always consult the Flight Crew Training Manual (FCTM) which provides information specific to the software version used at that particular airline.

Glossary

  • CDU – Computer Display Unit.

  • EFIS – Electronic Flight Instrument System.

  • FMA – Flight Mode Annunciator.

  • FMC – Flight Management Computer.

  • FMS - Flight Management System.

  • LVL CHG – Level Change.

  • LNAV – Lateral Navigation.

  • MCP – Mode Control Panel.

  • ND – Navigation Display.

  • PFD – Primary Flight Display


  • VNAV – Vertical Navigation.

ISFD Knob Fabricated

OEM ISFD (Image copyright Driven Technologies INC)

The Integrated Standby Flight Display (ISFD) is mounted in the stand-by instrument cluster in the Main Instrument Panel (MIP).  The ISFD provides redundancy should the Primary Flight Display (PFD) on the Captain or First Officer fail. 

The ISFD is not a common panel to find second hand, and working units are expensive to purchase.  I don't  have an OEM ISFD, but rather (at least for the moment) use a working virtual image displayed by ProSim737. 

ISFD knob.  Two versions: one replicates the taller NG style while the other is slightly shorter.  Although not functional, they provide a better representation of the plastic knob that previously was installed

Conversion of an OEM unit is possible, however, the unit would need to be fully operational, and  finding a working unit at a reasonable price is unlikely.  ISFDs are expensive and reuse is common.  If a unit does not meet certification standard, it's disposed of because it's broken and cannot be economically repaired.

ISFD Knob

The ISFD knob that came bundled with the MIP I purchased is very mediocre in appearance – in fact it's a piece of plastic that barely looks like a realistic knob.  I purposely have not included an image, as the design would be an embarrassment to the company that produced the MIP.

A friend of mine is a bit of a wizard in making weird things, so I asked him if he could make a knob for me.  He made two knobs – one based on the standard design seen in the Next Generation airframe and the other knob a shorter version of the same type. 

Knob being fabricated on a lathe

Attention to Detail

Attention to detail is important and each knob has the small grub screw and cross hatch design as seen on the OEM knob.  The knobs have been made from aluminum and will be primed and painted the correct colour in the near future.

A 2 axis CNC lathe was used to fabricate the knobs.  The use of a computer lathe enables the measurements of a real knob to be accurately duplicated, in addition to any design characteristic, such as cross hatching or holes to install grub screws.

Wind Correction (WIND CORR) Function - CDU

OEM 737 CDU showing WIND CORR display in Approach Ref page

Wind Correction (WIND CORR)

The approach page in the CDU has a field named WIND CORR (Wind Correction Field or WCF). 

WIND CORR can be used by a flight crew to alter the Vref + speed (speed additive) that is used by the autothrottle during the final approach.   This is to take into account wind gusts and headwind that is greater than 5 knots. 

Changing the Wind Correction to match increased headwind and gusts increases the safety margin that the autothrottle operates, and ensures that the autothrottle command a speed is not at Vref.

WIND CORR Explained

The algorithm of the autothottle includes a component that includes a speed additive.  The speed additive is 1.23 times greater than the stall speed of the aircraft (at whatever flap setting).  When the autothrottle is engaged, the speed additive is automatically added to Vref.   This provides a safety buffer to ensure that the autothrottle does not command a speed equal to or lower than Vref. This added speed is usually 'bled off' during the flare ensuring landing is at Vref.

Although the autothrottle algorithm is a sophisticated piece of software, there is a time lag between when the sensors register a change in airspeed to when the physcial engines increase or decrease their spool (power).   By having a speed additive (based on headwind and gust component) the speed of the aircraft (as commanded by the autothrottle) should not fall below Vref.

A Vref+ speed higher than +5 can be inputted when gusty or headwind conditions are above what are considered normal.  By increasing the additive speed (+xx), the  speed commanded by the autothrottle will not degrade to a speed lower than that inputted.

The default display is +5 knots.   Changing this figure will alter how the algorithm calculates the command speed for the autothrottle; any change will be reflected in the LEGS page, however not in the APPROACH REF page.

The data entered into the Wind Correction field will only be used by the Flight Management System (FMS) when the aircraft is following an RNAV approach, or when using VNAV to fly an approach that has been manually constructed in the CDU.  This is because these approach modes use the data from the FMS to fly the approach (as opposed to an ILS or other mode that doesn't use the FMS data). 

If hand flying the aircraft, or executing another approach type, Wind Correction is advisory (you will need to add the speed additive (Vref+ xx knots) by mental mathematics).

Important Points:

  • Wind Correction is automatically added to Vref when flying an RNAV approach, or when using VNAV to fly an approach that has been manually constructed in the CDU.

  • Wind Correction is advisory for all other approach types or when manually flying an approach; +xx knots must be added to Vref by mental mathematics.

How To Use WIND CORR

The WIND CORR feature is straightforward to use.   

Virtual CDU (ProSim737) showing the difference in landing speed with a Vref between a +5 and +13 Knot (Wind Correction) change.  Vref altered from 152 knots to 160 knots

Navigate to the approach page in the CDU (press INIT REF key to open the Approach Reference page).  Then double press the key adjacent to the required flaps for approach (for example, flaps 30).  Double selecting the key causes the flap/speed setting to be automatically populated to the FLAP/SPD line. 

Type the desired additive into the scratch pad of the CDU and up-select to the WIND CORR line.  The revised speed will change the original Vref speed and take the headwind component into account.  If you navigate to the LEGS page in the CDU, you will observe the change.

If the headwind is greater than 5 knots, then WIND CORR can be used to increase the additive from the default +5 knots to anything up to but not exceeding 20 knots. 

It’s important to understand that the figure generated in the CDU is the Vref speed.  This is the speed that the aircraft should be at when crossing the runway threshold or at a altitude of approximately 50 feet.  

To this speed you must add the appropriate wind correction - either by mental mathematics or by using WIND CORR (if flying an FMS generated approach).

Boeing state that the +XX knots should be bled off during the flare procedure ensuring that touchdown speed is at Vref, however this rarely occurs in real life.

Recall from above, that any change using the Wind Correction field will have no bearing on calculations, unless the aircraft is being flown in RNAV / VNAV, or the approach has been manually constructed in the CDU.

For a full review on how to calculate wind speed, refer to this article: Crosswind landing Techniques - Calculations. A prompt sheet is displayed for quick reference.         

Wind calculation cheat sheet

Important Variables - Aircraft Weight and Fuel Burn

To obtain the most accurate Vref for landing, the weight of the aircraft must be known minus the fuel that has been consumed during the flight.

Fortunately, the Flight Management System updates this information in real-time and provides access to the information in the CDU.  It's important that if an approach is lengthy (time consuming) and/or involves holds, the Vref data displayed on the CDU will not be up-to-date (assuming you calculated this at time of descent); the FLAPS/Vref display will show a different speed to that displayed in the FLAP/SPD display.  To update this data, double press the key adjacent to the flaps/speed required and the information will update to the new speed.

How To Manually Calculate Fuel Burn

If wishing to manually calculate the final approach speed well before the approach commences, then it's necessary to manually calculate the fuel burn of the aircraft.  Open the PROGRESS PAGE on the CDU and take note of the arrival fuel.  Subtract this value from how much fuel you have in the tanks - this is the fuel burn (assuming all variables are constant).

Interestingly, the difference that fuel burn and aircraft weight can play in the final Vref speed can be substantial (assuming all variables, except fuel, are equal).  To demonstrate:

  • Aircraft weight at 74.5 tonnes with fuel tanks 100% full – flaps/Vref 30/158.

  • Aircraft weight at 60.0 tonnes with fuel tanks 25% full   – flaps/Vref 30/142.

Important Points:

  • During the approach, V speeds are important to maintain.  A commanded speed that is below optimal can be dangerous, especially if the crew needs to conduct a go-around, or if winds suddenly increase or decrease.  An increase or decrease in wind may cause pitch coupling.

  • If executing an RNAV Approach or using VNAV, it's important to update the WIND CORR field to the correct headwind speed based on wind conditions.  This is because an RNAV approach and VNAV use the data from the Flight Management System (to which Wind Correction is added).

  • If an approach is lengthy (for example, during a STAR or when requested to hold), the Vref speed will need to be updated to take into account the fuel that has been used by the aircraft during the holding time. 

  • Changing the WIND CORR speed in the CDU, does not alter the Vref speed displayed on the Primary Flight Display (PFD).  Nor is the APPROACH REF page on the CDU updated.  The change is only reflected in the LEGS page.

  • Boeing state that the speed additive should be 'bled off' during the flare so that the actual landing speed is Vref.

Autoland

Autolands are rarely done in the Boeing 737, however, if executing an autoland, the WIND CORR field is left as +5 knots (default).  The autoland and autothrottle logic will command the correct approach and landing speed.

Simulated in Avionics Suite

WIND CORR may or may not be functional in the avionics software you use.  Wind Correction is functional in the ProSim737 avionics suite.

Additonal Information

A very good video that discusses this in detail can be viewed at FlightDeck2Sim.

 
 

Acronyms

  • CDU – Control Display Unit

  • FMC – Flight Management Computer

  • FMS – Flight Management System (comprising the FMC and CDU)

  • Vref - The final approach speed is based on the reference landing speed

  • Vapp – Vapp is your approach speed, and is adjusted for any wind component you might have. You drop from Vapp to Vref usually by just going idle at a certain point in the flare

  • Updated 21 March 2022 (increased clarity)

Differences in Colour, Manufacturer, and Layout in the Center Pedestal

There are several panels that make up the center pedestal, main instrument panel, and overhead in the Boeing 737 aircraft. Most of the panels are required by international law, and a carrier cannot fly if certain panels do not function correctly.

Although the aviation regulations require aircraft to have certain panels, there are panels that are airline specific. These panels are chosen when the aircraft is ordered from Boeing, or they may be installed at a later on. Similar to automobiles, there are a number of manufacturers of aviation panels and each panel, although having identical functionality may differ slightly.

All high-end simulators replicate the panels required by the authorities, and enthusiasts often fixate on a number of supposed issues. Namely:

(i)         The colour of the panel and lightplate;

(ii)        The position of the panel in the center pedestal;

(iii)       The backlighting of the lightplate (bulbs verses LEDs);

(iv)       The manufacturer of the panel, and;

(v)        The aesthetic condition of the lightplate.

Although seemingly important to a cockpit builder, to the casual observer, or indeed to many pilots, these attributes are of little consequence.  Nevertheless, it's understandable to a newcomer that all panels in the 737 Next Generation are identical between all aircraft.

Whilst it's true that all airlines must meet aviation standards for the type of operation they fly, the panel manufacturer and where in the pedestal the panel is located is at the discretion of the airline.  Furthermore, it's not uncommon to observe older style panels mixed with modern panels and to see lightplates that are illuminated by bulbs and LEDs side by side.

Note that some of this information probably pertains more to older Next Generation 737s than to the latest Next Generation released from Boeing.  I use the word 'panel' to denote an avionics module.

Air Alaska 737-700 pedestal.  Note higher than standard position of ACP panels and relocated position of the door lock panel.  Also high mounted position of rudder trim panel

Colour of Lightplates

The official colour shade used by Boeing is Federal Standard 5956 36440 (light gull grey).  However, OEM part manufacturers may use slightly different colour hues.  For example, IPECO use British Standard 381C-632 (dark admiralty grey) and Gables use RAL 7011.  This said, often an airline will 'touch up' a lightplate that is damaged or faded - this introduces a further colour variant. 

For example, a lightplate I acquired from a 737-500 airframe revealed three differing shades of grey beneath the final top coat of paint.  This is not to mention that, depending on the manufacturer of the lightplate, the final coat of paint may be matt, semi-matt or gloss.

From the perspective of an engineer, the colour (and to a certain extent aesthetic condition) is unimportant when replacing a defective part with another.  Time spent in the hanger equates to a loss in revenue by the airline.  Therefore turn-around times are as brief as possible and keeping an aircraft on the ground while procuring the correct shade of Boeing grey does not enter the equation.

Position of Panels in the Center Pedestal

Boeing recommends a more or less standard position for the essential panels in the center pedestal (NAV, COM, ADF, ASP, rudder trim, door lock and panel flood), however, the location of the panels is often altered by the receiving airline, and is to a certain extent is determined by what other panels are installed to the pedestal.  Areas (holes) in the pedestal not used by a panel are covered over with a grey-coloured metal blank.

LEFT:  This photograph of the center pedestal of a Boeing 737-500 was taken in 2016.  The aircraft is a freighter converted from a passenger aircraft.  Apart from the older style ACP panels, note the disparate displays between the NAV and COM radios.  Also note the position of the ADF radios and some of the other panels; they do not conform to what is usually thought of as a standard set-out.  Finally, note the scratches on the pedestal and on some of the panels and lightplates - they hardly look new.

Panels are manufactured by several companies, and often there appearance will differ slightly between manufacturer, although the panel's functionality will be identical.  The airline more often than not chooses which panel is used, and often the decision is biased by the cost of the panel.  Therefore, it's not uncommon to observe several airframes of a similar age with differing panels positioned in different areas of the center pedestal.

Panel Condition

Enthusiasts pride themselves in having a simulator that looks brand new.  However, in the real world a Level D simulator or flight deck rarely looks new after entering service.  Panels can be soiled and paint is chipped and scratched, and depending on age, some lightplates are faded to due to the high UV environment that is present in a flight deck.

So where am I going with this?  Enthusiasts strive to match their panels with those observed in a real airliner, however, more often than not this information comes from photographs distributed by Boeing Corporation, which nearly always depict panels in a standard position, especially in relation to the center pedestal. 

The variables noted by enthusiasts should not cause consternation, as real aircraft show similar variation.  Remember that in the real aircraft, colour, manufacturer, and to a certain extent aesthetic condition is not important - functionality is.

Backlighting and Dimming with OEM and Reproduction Panels

FDS-IBL-DIST-DIM.  A card that makes diming backlighting very easy.  Potentiometer is not shown

Many enthusiasts are now using Original Aircraft Equipment (OEM) panels in their simulators.  These panels are connected to Flight Simulator using a variety of interface cards.  Unless the flight deck uses all OEM panels, or all reproduction panels, there will be a difference in backlighting when the light plates are illuminated.

Reproduction panels, with the exception of expensive very high end types, will have exceptionally bright backlighting.  Manufacturers of reproduction panels want their panel to look good and appeal to a prospective buyer – this is why they have bright backlighting.  In contrast, OEM panels do not have  bright backlighting, and in some cases, depending upon the manufacturer of the panel, the backlighting will appear rather dim.  

Therefore, the brightness of the backlighting when using ‘run of the mill’ reproduction panels is not realistic in comparison to that observed in a real aircraft.

So how does a cockpit builder solve this conundrum of brightness if he or she has a mix of reproduction and OEM panels.  The solution is very simple – install a dimmer switch into your flight deck.

Dimmer Control

There are a number of 5 volt dimmer switches on the market and some are better than others.  For those with electrical knowledge it’s relatively straightforward to make your own dimmer switch, but what about the rest of us?  An excellent solution is the distribution board with built in dimmer control manufactured by Flight Deck Solutions (FDS).  The board keeps with the principle of KIS (keep it simple).  

FDS-IBL-DIST-DIM

The distribution board is well made, small, is fuse protected, and have the capability to connect up to 14 accessory LEDS or bulbs via propriety board connectors.  The board also can be used as a slave, meaning it can be daisy-chained to another board to increase the number items attached.

The distribution board includes a pre-wired metal potentiometer which allows all the LEDS/bulbs attached to the board to be dimmed from on to off or anywhere in-between.  The potentiometer is a standard size and fits the hole located in the panel lights panel on either a reproduction panel or an OEM panel.

One limiting feature that should be noted is that each distribution board will only support 10 amps - the rating of the fuse.  Therefore, depending upon the number of panels that you wish to connect to the board, it may be necessary to use two boards in parallel rather one board or an extension to the board.

Of more importance, the board operates flawlessly and is a very easy solution to maintaining an even brightness across reproduction and OEM panels; adjust the brightness of the reproduction panels to the same level as the OEM panels.

Connection

Connection is straightforward and requires +- 5 volts to be connected to the board.  Each LED (or bulb) that requires dim control is then connected to the board connectors.  If using an FDS panel this is very easy as the FDS panels already use the correct female attachment plugs (FDS also use bulbs and not LEDS).  Failing this, a little extra work is required to source the correct plugs and wire them to the +- wires that connect to the light plate.

Bulbs and LEDS

On another note, with the exception of late model airframes, the Next Generation B737 use 5 volt incandescent bulbs in their panels for backlighting.  This is in contrast to reproduction panels that, for the most part, use LEDS.  

The difference between bulbs and LEDS, other than construction, is the temperature they generate when turned on.  A bulb will generate considerable heat and the colour of the light will appear as a warmer hue.  A LED does not generate heat when turned on.  Therefore, an LED will have a cooler temperature and the colour of the light will be colder and more stark in its appearance.

However, before changing out all your bulbs or LEDS to maintain colour consistency, study the flight deck of a real aircraft.  Panels on all aircraft fail or need upgrading from time to time.  Therefore, it is not unrealistic to have a flight deck consisting of both LEDS and bulbs.  Airlines are in the business of making money, and pilots fly.  Neither are particularly interested in whether the ADF radio has a bulb or LED.

Additional Information

Soar-By-Wire has also discussed this subject.  Although his information relates to the Airbus, the same procedure can be done for Boeing OEM panels.

Disclaimer

I do not represent Flight Deck Solutions or any other manufacturer and have no received any fee or reward for discussing one of their interface components.

Further information pertaining to the distribution board can be found on the Flight Deck Solutions website.

A fellow enthusiast has written more information on his website about the distribution board as it relates to Airbus - Soarbywire.  What he has written is well worth the time reading.

Sounds Reworked - Flight Sim Set Volume (FSSV) - Review

Engine sounds will be at their highest at takeoff

Immersion is a perception of being physically present in a non-physical world.  The perception is created by surrounding the user of the simulator in images, sound or other stimuli that provide an engrossing total environment.  When something does not replicate its real world counterpart, the illusion and immersion effect is degraded.

Engine Sound Output

The sound output generated by a jet aircraft as heard from the flight deck is markedly different when the aircraft is at altitude.  This is because of differences in air density, temperature, the speed of the aircraft, drag, and thrust settings.  The noise emitted from the engines will always be highest at takeoff when full thrust is applied.  At this time, the noise generated from wind blowing over the airframe will be at its lowest.  At some stage, these variables will change and wind noise will dominate over engine noise.

As an aircraft gathers speed and increases altitude, engine sound levels lower and wind levels, caused by drag, increase.  Furthermore, certain sounds are barely audible from the flight deck on the ground let alone in the air; sounds such the movement of flaps and the extension of flight spoilers (speedbrake).

Being a virtual flyer, the sound levels heard and the ratio between wind and engine sound at altitude is subjective, however, a visit to a flight deck on a real jet liner will enlighten you to the fact that that Flight Simulator’s constant-level sound output is far from realistic.

Add On Programs

Two programs which strive to counter this shortcoming (using different variables) are Accu-Feel by A2A Simulations and FS Set Volume (FSSV).  This article will discuss the attributes of FSSV (Sounds Reworked).

Flight Sim Set Volume (FSSV)

FSSV is a very basic program that reads customized variables to alter the volume of sound generated from Flight Simulator.  The program is standalone and can be copied into any folder on your computer, however, does require FSUIPC to connect with Flight Simulator.  Wide FS enables FSSV to be installed on a client computer and run across a network.  

The following variables can be customised:

(i)     Maximum volume

(ii)    Minimum volume

(iii)   Upper mach threshold

(iv)   Lower mach threshold

(v)    Engine volume ratio

Each of the variables will alter to varying degrees the Mach, engine %N1, rounded engine speed and volume percentage.  

For the program to have effect it must be opened either prior to or after the flight simulator session is opened. 

FSSV pop-up screen showing customised variables (default) that can be set and current reads-outs for the simulator session

It’s an easy fix to automate the opening of the program to coincide with Flight Simulator opening by including the program .exe in a batch file

A pop-up window, which opens automatically when the program is started, will display the variables selected and the outputs of each variables.  If the window is kept open, the variables can be observed ‘on the fly’ as the simulation session progresses.  Once you are pleased with the effects of the various settings, a save menu allows the settings to be saved to an .ini file.  The pop-up window can then be set to be minimized when you start a flight simulator session.  

How FSSV Works

The program reads the sound output from the computers primary sound device and alters the various sound outputs based upon customized variables.  The program then lowers the master volume at the appropriate time to match the variables selected.  FSSV will only alter the sound output on the computer that the program is installed.  Therefore, if FSSV is installed to the same computer as Flight Simulator (server computer) then the sound for that computer will only be affected.

Possible Issue (depends on set-up)

An issue may develop if FSSV is installed on a client computer and run across a network via Wide FS, then the program will not only affect the sound output from the server computer, but it also will affect the sound output from the client computer.  

A workaround to rectify this is to split the sound that comes from the sever computer with a y-adapter and connect it to the line-in of another computer, or use a third computer (if one is spare).

In my opinion, it’s simpler to install and run the program via a batch file on the server computer that flight simulator is installed.  The program is small and any drop in performance or frame rates is insignificant.

Summary

The program, although basic, is very easy to configure and use - a little trial and error should enable the aircraft sounds to play with a higher degree of realism.  However, the level that you alter the variables to is subjective; it depends on your perception to the level of sound heard on a flight deck – each virtual flyer will his or her own perception to what is correct. 

The program functions with FSX and P3D flawlessly. 

Finally, If you are unhappy with the result, it’s only a matter of removing/deleting the folder you installed the program to, or close the program during your simulator session to return the sound levels to what they previously were. 

  • FS Set Volume can be downloaded at no charge here

Video

The below video is courtesy of the FSSV website.

 
 
 

Conversion of OEM CDU - Part Two

OEM CDU operational with ProSim737

In this second article, I will explain how the OEM Control Device Unit (CDU) was converted to enable a SimStack Foundation Board to be installed inside the unit and connected to ProSim737. 

SimStacks are manufactured by Simulator Solutions, which is a Sydney based company in Australia and their foundation boards can be used with ProSim737 and ProSim320 avionics suites. 

This is but one method to convert an OEM item to be used with flight simulator.

This article will mainly address the mechanical conversion of the CDU.  A future article, after flight testing,  will provide a review of SimStacks interface cards.

Conversion

Many of the OEM parts used in the simulator have been converted using Phidget cards, and to a lesser extent Leo Bodnar and PoKeys interface cards.  Phidgets provide a stable platform, despite the disadvantage that they, at time of writing, can only connect via USB to the server computer, and don’t enable every OEM function to be used in ProSim-AR.  The primary advantage of using Phidgets is that they have been used in a wide variety of applications, are inherently stable, and their configuration is well documented.

I decided that, rather than use Phidgets, a different system would be trailed to interface the CDU with ProSim737. 

he SimStack Foundation Board mounted on an angular bracket inside the CDU.  Fortunately there is ample room to mount the board inside the CDU

SimStacks by Simulator Solutions

The conversion of the CDU was done in collaboration with Sydney-based company Simulator Solutions Pty Ltd.  Simulator Solutions use their propriety interface boards called SimStacks to convert OEM parts for use in commercial-grade simulators.

SimStacks is a modular, stackable, and scalable hardware interface that is designed to integrate OEM parts into your simulator with little or no modification.    One of the many advantages in using a SimStack board is that the interface can connect with either the server or client computer via Ethernet (as opposed to Phidgets). 

To date, Simulator Solution’s experience has been predominately with the conversion of B747 parts and Rodney and John (owners) were excited to have the opportunity to evaluate their software on the 737 platform using ProSim737. 

Converting the CDU - Choose Your Poison

There are two main camps when discussing how to convert an OEM part.  The first is to use as much of the original wiring and parts as possible.  The second is to completely ‘gut’ the part and convert it cleanly using an interface that connects seamlessly with the avionics software in use (ProSim-AR).  A third option, although expensive and in many respects ‘experimental’, is to use ARINC 429. 

ARINC 429 is a protocol used in real aircraft to enable panels etc to be connected with the aircraft’s systems, and although it can be used in a simulated environment, it’s not without its shortfalls, in particular, the use of AC power (in contrast to DC power).

To use SimStacks the internal components of the CDU had to be removed, with the  exception of the internal shelf divider and keypad.  In hindsight, the pin-outs of the Canon plugs could have been used, but in doing so a female Canon plug would have been required, and for the use of a couple of pins, the price of a Canon female plug was expensive.

Keypad and Screen

The keypad and screen are the two most important parts of the CDU. 

The keypad forms part of the lightplate.  The backlighting for the keypad is powered by 21 5 Volt incandescent bulbs, strategically located to ensure even backlighting of the keys.

table 1: provides an overview of bulb location, part number and quantity

Like anything, bulbs have a limited left and, although OEM bulbs are renown for their longevity, there is always a chance that some bulbs are broken.  In this case, there were 3 bulbs that needed replacement.

Disassembling and removing the keypad from the main body of the CDU is straightforward; several small Philips head screws hold the keypad in place.  Once the keypad has been removed, any ‘blown’ bulbs can be replaced. 

The most important area is the keypad is what is called the terminus (bus).  Several wires from the keypad travel to the bus and then to the various (now removed) parts in the CDU.  The Simstack Foundation Board is wired to the bus, therefore, care must be taken to not damage these wires between the bus and the keypad. 

737 CL CDU showing older green coloured text displayed on CRT screen

I found that the wires were quite short and needed to be lengthened; this can be done by splicing longer wire to the existing wire.  Although it's possible to replace the wire to the keypad, this would entail re soldering the wires to the various keypad points - a process that requires very exact soldering.

CRT screen showing thick curved glass

CRT and LCD Screen

The Classic CDU from airframes up to the Boeing 737-500 is fitted with a solid glass cathode ray tube (CRT) screen. 

The CRT screen is approximately 2 cm thick, curved in design, and fits snugly within the display frame of the CDU.  Although it’s possible to make this screen operational, the display will be mono-colour (green) and the screen resolution poor.  Therefore, the CRT was replaced with a custom-sized high resolution colour LCD screen.

To replace the CRT screen is not without its challenges.  The first being that the LCD screen is not 2 cm in thickness and will not fit snugly within the curved display recess of the CDU frame.  To rectify this shortfall, a piece of clear glass must be ground to correctly fit within the frame.  This piece of glass replaces the 2 cm thick, curved CRT glass.

Photo showing how the thin LCD screen was secured with tape the glass screen.  Although the process appears rudimentary, it's functional

The thin LCD screen is installed directly behind the clear glass using high density tape.  Commercial grade double-sided sticky tape is the easiest method, but it is rudimentary.  The reason that tape is used, is that should the screen fail, it’s easy to remove the tape, install a replacement screen, and then tape the screen in place.

During the design phase, it was thought that the thick piece of glass would cause a refraction problem.  However, although the theory suggests refraction will occur, the practical application has been such that any refraction is not readily noticeable.

Installing the SimStacks Foundation Board and Screen Controller Card

To enable the CDU to operate, four items need to be mounted inside the CDU.

(i)   The generic Interface card that controls the LCD screen;

(ii)   The LCD screen controller (buttons that control brightness, contrast, etc);

(iii)  The SimStack Foundation Board; and,

(iv)  The wiring to connect the keyboard to the Foundation Board.

Fortunately, there is ample room in the cavernous interior of the CDU to fit these items. 

The SimStack Foundation Board is mounted on an angular metal bracket that is attached directly to the bottom of the CDU, while the LCD interface card has been installed on the upper shelf along with the screen controller.  A ribbon cable connects the LCD screen to the interface card while a standard VGA cable connects the LCD screen to the client computer and Ethernet switch. 

The SimStack Foundation Board is Ethernet ready and requires a standard Ethernet cable (CAT 6) to connect from the card to an Ethernet switch (located behind the MIP).  In addition to the Ethernet  and VGA cable, six power wires leave the CDU via the rear of the casing; four from the SimStack Foundation Board (5 and 12 volts +-) and two from the keypad (5 volts +-) to control the backlighting.

The specialist switch and wiring (Ethernet, power and VGA cables) extruding from the rear of the CDU

Specialist Switch and Power Supply

A standard two-way toggle switch is mounted to the rear of the CDU casing. 

This switch is used to control whether the LCD screen, used in the CDU, is always on, or is only turned on when ProSim-AR is activated.

To operate the CDU requires a 5 and 12 volt power supply.  The backlighting of the keypad is powered by 5 volts while the SimStack Foundation Board and CDU operation require 12 volts.

Backlight Dimming (keypad)

To enable the CDU keypad to be dimmed, the 5 volt wires are connected to a dedicated 5 volt Busbar located in the center pedestal.  This Busbar is used to connect the backlighting from all OEM panels.  The Busbar is then connected to the panel knob on the center pedestal.  The ability to turn the backlighting on and off is controlled by opening or closing a 12 volt relay (attached in line between the panel knob and Busbar).  Dimming is controlled by a dimmer circuit (see earlier article).

Installing the OEM CDU to Flight Deck Solutions MIP

It can be challenging attempting to install OEM panels, gauges and other items to a reproduction Main Instrument Panel (MIP).  Unfortunately, no matter what the manufacturer states, many MIPS do not comply with real world measurements.  

Before and after photograph of the FDS CDU bay showing the small flange from the shelf that needed to be trimmed to enable the CDU to slide into the bay recess.  A small notch was made at the corner to facilitate the safe routing of the wires used to enable the Lights Test

The MIP skeleton is manufactured by Flight Deck Solutions (FDS) and the CDU bay, although fitted with OEM DZUS rails, is designed to fit FDS’s propriety CDU unit (MX Pro) and not an OEM unit. 

The casing for the OEM CDU is much longer than the FDS CDU and measures 20 cm in length.

The FDS MIP design is such that the aluminum shelf (used by FDS to mount various interface cards) protrudes slightly into the rear of the CDU bay.  This protrusion stops the OEM casing from sliding neatly into the bay to its fullest extent.  To enable the CDU to slide into the CDU bay, the shelf must be ‘trimmed’.

To trim the metal away from the shelf, a small metal saw was used, and although an easy task, care must be taken not to ‘saw away’ too much metal.  Once the piece of offending aluminum is removed, the CDU slides perfectly into the bay, to be secured by DZUS fasteners to the DZUS rail.

Functionality and Operation

The CDU is not intelligent; it’s basically a glorified keyboard that must be interfaced with ProSim-AR to enable the CDU to function correctly.  The fonts and colour of the fonts is generated by the avionics suite (in this case ProSim-AR, but arguably it could also be Sim Avionics or Project Magenta). 

To enable communication between the avionics suite and the SimStack Foundation Board, proprietary software must be installed.  This software has been developed by Simulator Solutions.

SimStack Software (simswitch)

Screen grab showing SimSwitch software User Interface.  SimSwitch is standalone once the initial configuration has been completed.  The software can be configured to open in minimised mode via a batch file

To enable communication between the Foundation Board and ProSim737, propriety software, called SimSwitch must be installed to the computer that has the CDU connected. 

SimSwitch is a JAR executable file, that when configured with the correct static IP address and port numbers, provides communication between ProSim-AR (on the server computer) and the network (clients).  The switch must be opened for communication to occur between the Foundation Board, SimSwitch and ProSim737.  The jar file can easily be included into a batch file (with timer command) for automatic loading when flight simulator is used.

When opened, SimSwitch displays the User Interface.  The User Interface displays all OEM panels that have been connected using a SimStacks, can be used to monitor connected panels, and can display debugging information (if required).

Independent Operation

The Captain and First Officer CDUs are not cloned (although this is easy to do), but operate as separate units.  This is identical to the operation in the real aircraft, whereby the Captain and First Officer are responsible for specific tasks when inputting the information into the CDU.

First Officer CDU

The First Officer CDU will be converted using a similar technique, with the exception that this unit will be converted more ‘cleanly’.  Rather than use an angled plate on which to attach the SimStacks Foundation Board, a solid aluminum plate will be used.  The LCD screen controller card will also be attached to the rear of the LCD screen.  Finally, to enable fast and easy removal of the CDU, the connection of the Ethernet cable will be outside of the unit.

Additional Information

SoarByWire (another enthusiast) has written an excellent article dealing with interfacing SimStacks.

Below is a short video demonstrating the operation of the OEM CDU using ProSim737.

Main points to note in the video are:

  • Heavy duty tactile keys.

  • The definite click that is heard when depressing a key.

  • The solid keypad (the keys do not wobble about in their sockets).

  • Although subjective, the appearance of the OEM CDU looks more aesthetically pleasing that a reproduction unit.

 
 

Final Call

The conversion has been successful and, when connected with ProSim737 via SimSwitch, all the functions available in the CDU work correctly.

Glossary

  • ARINC 429 –  A standard used to  address data communications between avionics components.  The most widely used  standard is an avionics data bus.  ARINC 429 enables a single transmitter to communicate data to up to 20 receivers over a single bus.

  • Standalone – Two meanings.  Operation does not require an interface card to be mounted outside of the panel/part; and, In relation to software, the executable file (.exe) does not need to be installed to C Drive, but can be executed from any folder or the desktop.

  • Updated for clarity and information 12 June 2020.