<version-desc>Display the current FlightGear version</version-desc>
<fg-root-desc>Specify the root data path</fg-root-desc>
<fg-scenery-descn="0">Specify the scenery path(s);</fg-scenery-desc>
<fg-scenery-descn="1">Defaults to $FG_ROOT/Scenery</fg-scenery-desc>
<fg-aircraft-desc>Specify additional aircraft directory path(s) (alternatively, you can use --aircraft-dir to target a specific aircraft in a given directory)</fg-aircraft-desc>
<download-dir-desc>Base directory to use for aircraft and scenery downloads (the TerraSync scenery directory may be specifically set with --terrasync-dir)</download-dir-desc>
<load-tape-desc>Load recording of earlier FlightGear session. For <name>, if <name> ends with .fgdata it is treated as the local path of the recording file; otherwise we form the local path by prepending <name> with the tape directory and appending ".fgtape". For <url> (starting with http:// or https://) we download the remote recording (which must be a Continuous recording) in the background to a url-dependent filename while replaying it; if the url-dependent filename already exists it is assumed to be a truncated download and we only download any remaining data.</load-tape-desc>
<no-default-config-desc>Do not load any default configuration files (like .fgfsrc) unless explicitly specified with --config.</no-default-config-desc>
<allow-nasal-read-desc>Allow Nasal scripts to read files from directories listed as path (separate multiple paths with a semicolon (Windows) or a colon (UNIX)). By default, for security reasons, Nasal scripts can only read data from certain directories, such as $FG_ROOT, $FG_HOME, etc.</allow-nasal-read-desc>
<ignore-autosave-desc>Ignore the autosave file, i.e. the settings saved in this file will not be loaded during startup, nor will the settings be saved to this file when closing the simulator</ignore-autosave-desc>
<units-feet-desc>Use feet for distances</units-feet-desc>
<units-meters-desc>Use meters for distances</units-meters-desc>
<json-report-desc>Print a report in JSON format on the standard output, giving information such as the FlightGear version, $FG_ROOT, $FG_HOME, aircraft and scenery paths, etc.</json-report-desc>
<jsbsim-output-directive-file-desc>Log JSBSim properties in a CSV file. An output directives file contains an <output type="CSV"></output> element, within which should be specified the parameters or parameter groups that should be logged.</jsbsim-output-directive-file-desc>
<data-desc>Specify an additional base data directory (FGData), before the $FG_ROOT directory</data-desc>
<fdm-descn="0">Select the core flight dynamics model</fdm-desc>
<fdm-descn="1">Can be one of jsb, larcsim, yasim, magic, balloon, ada, external, or null</fdm-desc>
<aero-desc>Select aircraft aerodynamics model to load</aero-desc>
<model-hz-desc>Run the FDM this rate (iterations per second)</model-hz-desc>
<speed-desc>Run the FDM 'n' times faster than real time</speed-desc>
<notrim-descn="0">Do NOT attempt to trim the model</notrim-desc>
<notrim-descn="1">(only with fdm=jsbsim)</notrim-desc>
<trim-descn="0">Trim the model</trim-desc>
<trim-descn="1">(only with fdm=jsbsim)</trim-desc>
<on-ground-desc>Start at ground level (default)</on-ground-desc>
<in-air-desc>Start in air (implied when using --altitude)</in-air-desc>
<wind-desc>Specify wind coming from DIR (degrees) at SPEED (knots)</wind-desc>
<random-wind-desc>Set up random wind direction and speed</random-wind-desc>
<turbulence-desc>Specify turbulence from 0.0 (calm) to 1.0 (severe)</turbulence-desc>
<ceiling-desc>Create an overcast ceiling, optionally with a specific thickness (defaults to 2000 ft).</ceiling-desc>
<aircraft-dir-desc>Specify the exact directory to use for the aircraft (normally not required, but may be useful). Interpreted relatively to the current directory. Causes the <path-cache> from autosave_X_Y.xml, as well as --fg-aircraft and the FG_AIRCRAFT environment variable to be bypassed.</aircraft-dir-desc>
<!-- Position and Orientation options -->
<position-options>Initial Position and Orientation</position-options>
<airport-desc>Specify starting position relative to an airport</airport-desc>
<parking-id-desc>Specify parking position at an airport (must also specify an airport)</parking-id-desc>
<carrier-position-desc>Specify a starting position relative to the carrier where you can use the predefined abeam (start on downwind abeam) or FLOLS (start on final approach) values, or specify the name of the carrier's parking position. Must also specify a carrier.</carrier-position-desc>
<graphics-preset-desc>Set graphic options from one of the presets</graphics-preset-desc>
<compositor-desc>Specify the path to XML file for multi-pass rendering. The path is relative to $FG_ROOT (defaults to Compositor/default.xml).</compositor-desc>
<view-offset-desc>Specify the default forward view direction as an offset from straight ahead. Allowable values are LEFT, RIGHT, CENTER, or a specific number in degrees</view-offset-desc>
<httpd-desc>Enable http server on the specified address. Specify the port or address:port to bind to.</httpd-desc>
<proxy-desc>Specify which proxy server (and port) to use. The username and password are optional and should be MD5 encoded already. This option is only useful when used in conjunction with the real-weather-fetch option.</proxy-desc>
<telnet-desc>Enable telnet server on the specified port</telnet-desc>
<jpg-httpd-desc>Enable screen shot http server on the specified port (replaced by --httpd)</jpg-httpd-desc>
<allow-nasal-from-sockets-desc>Remove security flag, which means that network connections will be allowed full access to the simulator including running arbitrary scripts. Ensure you have adequate security (such as a firewall which blocks external connections).</allow-nasal-from-sockets-desc>
<disable-sentry-desc>Disable crash and error reports from being sent to the development team for analysis</disable-sentry-desc>
<enable-sentry-desc>Enable crash and error reports to be sent to the development team for analysis</enable-sentry-desc>
<log-dir-desc>Log to directory DIR. The special value 'desktop' causes logging to the desktop (OS-dependent location). This option may be given several times, using a different value each time. Inside the specified directory, the written log file is named FlightGear_YYYY-MM-DD_<num>.log, where <num> takes the values 0, 1, 2, etc.</log-dir-desc>
<uninstall-desc>Remove $FG_HOME directory. For Windows, it additionally removes TerraSync, Aircraft and TextureCache directories from download directory.</uninstall-desc>
<multiple-instance>multiple instances can be used</multiple-instance>