3 JSBSim is an ongoing attempt at producing an OO Flight Dynamics Model
4 (FDM) to replace LaRCsim as the default FDM for FlightGear. It can
5 also be used standalone.
7 JSBSim uses config files to represent aircraft, engines, propellers,
8 etc. Also, the flight control system is described in the config
9 file. Normally, for use with FlightGear, the config files are named
10 this way [case is significant]:
12 <FG_ROOT>/Aircraft/<aircraft name>/<aircraft name>.xml
14 Engines are named like this:
16 <FG_ROOT>/Engines/<engine name>.xml
18 Aircraft and engine config files are present in the FGFS Base package
19 which must be downloaded. See the FlightGear web site for more
22 How to run FGFS using JSBSim
24 All the various FDMs are currently compiled into FGFS. You can specify
25 which FDM you want at run time. You can also specify which aircraft
26 you want. Currently, for JSBSim only the X-15 and C-172 aircraft are
27 available. Here is an example command line used to start up FlightGear
28 using JSBSim as the FDM:
30 fgfs --fdm=jsb --aircraft=X15 --units-feet --altitude=60000 --uBody=2000 --wBody=120
34 fgfs --fdm=jsb --aircraft=c172
36 [Note: uBody is the forward velocity of the aircraft, wBody is the
37 downward velocity - from the aircraft point of view. This essentially
38 means that the aircraft is going forward fast and has an angle of
39 attack of about 4 degrees or so]
41 The first command line sets up the initial velocity and altitude to
42 allow the X15 to glide down. Note that if you fire up the engine, it
43 will burn for only about two minutes and then run out of fuel - but
44 you will go very, very fast! The second command line example will
45 start up the C172 on the end of the runway.
47 Check out the JSBSim home page at http://jsbsim.sf.net. Please report
48 any bugs to jsb@hal-pc.org, or apeden@earthlink.net, or post on the
49 jsbsim web site using the SourceForge bug tracking system for the
52 JSBSim is written by Jon S. Berndt and Tony Peden with contributions
53 by other FlightGear programmers, as well.