Aero-Matic is an internet application that uses an HTML interface to collect user-submitted
data on an airplane, then generates configuration files for use with
the JSBSim Flight Dynamics Model.
Aero-Matic tries to strike a balance
between simplicity and accuracy when modeling an airplane. The generated
configuration files will result in a plausible airplane model, and
is based on only a few data points that should be easily available from books or
internet sources. For a description of how Aero-Matic creates these files see
How to use Aero-Matic
Lets assume we want to make a model of the MiG-21. In this case we will need
two configuration files, an aero configuration, and an engine
configuration. Obviously we won't need a propeller configuration for the MiG-21.
The first step is to open aeromatic2.html in a browser. Step one in
aeromatic2.html is to
define an engine for the MiG-21. From The Encyclopedia of World Airpower
1 I find the following information on the engine used by the MiG-21.
Name: Tumansky_R25, type: Turbine, thrust (without afterburning): 10000 lb.,
and afterburning is installed, but water-injection is not. Note that the name
you chose for your engine should be a suitable file name, so only use appropriate
When you click on the "generate" button Aero-Matic will send the information to
engine2.php, which will do some calculations and send the results back to you.
The results will look like garbage because the configuration file was not meant to
look nice in a browser window. If you view the document source you will see the
file as it really is. Save this file with the file name Tumansky_R25.xml,
and place it in the $FGROOT/Engine directory with all the other engines.
Use your browser's "back" button to return to aeromatic2.html. Skip over the
propeller form and fill in the aero form. You must first select a system of units,
either English or metric. You cannot mix units! Now for the airplane data. For the
MiG-21 I have the following data. Name: Mig21, type: Single Engine Fighter, maximum
takeoff weight: 22,000 lb., span: 23.5 feet, length: 51.75 feet, wing area: 247 square
feet, tricycle landing gear (meaning the third wheel is in front of the main wheels),
one engine, engine type: Turbine, engine layout: aft fuselage. My source doesn't
say whether the MiG-21 had a yaw damper, but since it's a high-performance jet I'll
assume it needs one.
Now click on "generate" and the data will be sent to
aero2.php, which will do some calculations and return the configuration file to you.
As with the previous configuration file, it will look like garbage in your browser
window, but will look properly if you view the document source. Save this file as
Mig21.xml, and place it in a $FGROOT/Aircraft/Mig21 folder. You will now have
to open the file in a text editor and make a change. In the Propulsion section of
the aero file you will find a reference to the file name of your engine,
"Mig21_engine". Edit this name to read "Tumansky_R25". Your Mig-21 will now be
matched with a correct engine.
If you model a multi-engined airplane you must make the above change for each engine.
If you are modeling a propeller-driven airplane you must also change the thruster
file name to reflect the file name of the propeller configuration file. This must
be done for each propeller.
NOTE!! Be aware that some browsers can be configured to add HTML tags and make other changes
to files without telling you. This will prevent Aero-Matic from working! Also,
some browsers will reload the current page when displaying the document source. This
may result in a bad document. Also, watch out for browsers that are set to fetch cached
pages rather than new ones.
1The Encyclopedia of World Airpower, ed. Bill Gunston, Crescent Books,
New York, 1981
12 Aug 2003