With the late addition of the operational carrier in FSX Acceleration, we didn't get all the information about the launch bar into the SDK. The following is information that should fill in the gaps and help aircraft and ship designers create their carriers and aircraft.
The catapult launch system is designed to simulate a modern catapult assisted takeoff from a large flat-decked aircraft carrier. It is used in a number of missions featuring the F-18 Hornet. To specify that a ship has one or more catapults, runways and arrestor cables, the appropriate Attach Points need to be added to the model.
For the carrier runway add an attachpt_runway_start, an attachpt_runway_end and an attachpt_runway_edge attach point. The attachpt_runway_edge point defines the half-width of the runway, and should be to starboard of attachpt_runway_start. A carrier cannot have more than one runway.
For each catapult required add an attachpt_catapult_start_n, attachpt_catapult_end_n, and an attachpt_blast_shield_n. The start position is the point where the aircraft should connect its launch bar. The blast shield point should be the center hinge of the shield.
For each arrestor cable required, add an attachpt_cable_n_1 and attachpt_cable_n_2.
Note that n is a number between 1 and 4, and a maximum of four operational catapults, blast shields and arrestor cables is supported.
There is a setting in the FSX.cfg file -- in the [Realism] section:
CatapultForceLimiter=1. With this set to 1 only flighter type aircraft can be catapulted. Set this to 0 to enable the catapult systems to generate the required force for any type of aircraft.
Catapult Assisted Takeoff
To add a launch bar to an aircraft, either set the attachpt_Launch_Bar_Pivot and attachpt_Launch_Bar_Lug attach points in the model, or define a [launch_assistance] entry in the aircraft configuration file. An entry in the configuraion file will override the attach points, if they exist.
Use one of the KEY_TOGGLE_LAUNCH_BAR_SWITCH or KEY_SET_LAUNCHBAR_SWITCH key events to drop the launch bar from the nose of the aircraft. This is an animated feature of the F-18, and the launch bar should be visible.
The aircraft should be moved into position on the catapult, and then one of the KEY_TAKEOFF_ASSIST_ARM_SET or KEY_TAKEOFF_ASSIST_ARM_TOGGLE key events should be used to attach the launch bar to the bogie of the catapult (which is not animated). If the aircraft is not in the correct location, the connection will not be made. If all goes well, the connection will be made, and the blast shield will be raised.
The KEY_TAKEOFF_ASSIST_FIRE event key is used to fire the catapult. The user cannot control the position of the aircraft until the aircraft clears the deck. If for any reason the assist arm is unset, again using the KEY_TAKEOFF_ASSIST_ARM_SET or KEY_TAKEOFF_ASSIST_ARM_TOGGLE key events, then the blast shield will also be retracted. The aircraft can then be moved away from the catapult.
Landing Using Arrestor Cables
To add a tailhook to an aircraft, either set the attachpt_tailhook_pivot and attachpt_tailhook_hook attach points in the model, or define a [tailhook] entry in the aircraft configuration file. An entry in the configuraion file will override the attach points, if they exist.
Use one of the KEY_SET_TAIL_HOOK_HANDLE or KEY_TOGGLE_TAIL_HOOK_HANDLE key events, or the TAILHOOK POSITION simulation variable, to set the tail hook in position.
Land on the appropriate spot on the carrier. There are typically four arrestor cables. If the aircraft does not land with excessive speed, it will be brought to a halt and pulled back a short distance. If it does land with excessive speed the cables will not prevent the aircraft going off the deck. Cable breaks are not simulated. The aircraft can be parked on deck, perhaps using the KEY_TOGGLE_WING_FOLD or KEY_SET_WING_FOLD key events to fold the wings.
Entries in Aircraft Config
[tailhook]
If a tailhook entry is made, it will override the attachpt_tailhook_pivot and attachpt_tailhook_hook entries for the aircraft, if these attach points exist.
tailhook_length Length of tailhook in feet. FA-18 Hornet( tailhook_length = 4.5 )
tailhook_position Tailhook pivot point relative to datum reference point. FA-18 Hornet( tailhook_position = -49.0, 0, -2.5 )
[launch_assistance]
If a launch_assistance entry is made, it will override the attachpt_Launch_Bar_Pivot and attachpt_Launch_Bar_Lug entries for the aircraft, if these attach points exist.
launch_bar_pivot Launch bar pivot point relative to datum reference point. launch_bar_pivot = 5.0, 0.0, -1.0
launch_bar_lug Launch bar lug point relative to datum reference point. launch_bar_lug = 5.0, 0.0, -4.5
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