The RCS thrusters allow the Shuttle to change attitude, and perform various on-orbit maneuvers. The RCS thrusters are small rocket engines operated either by hand controllers in the cockpit known as the RHC/THC controllers, or by the Digital Auto Pilot (DAP). The RCS engines use an Hypergolic Fuel which lights up when its two components (Fuel and Oxidizer) come into contact. This allows the system to be almost fail-safe due to the simple nature of the system.
RCS allows control over 6 axis of Movement.
Pitch, Roll and yaw are the rotational axis,
X, Y and Z are the Transitional axis, those are usually comparable to Forward/Back (X), Left/Right (Y) and Up/Down (Z).
|Diagram taken with permission from the SSM2007 Commander's Reference Manual|
The Shuttle has two positions to “Drive” the shuttle in orbit from. int the front - the commander's seat, and in the rear of the cabin, the left hand side post. the rear controller has two operating modes, -X and -Z, selected from the Aft sense switch (located on the A6 Panel. These modes determine the axis of reference for the controller allowing the pilot to more naturally maneuver the Shuttle while looking at the target without the need to “translate” the input in his head as shown in the next illustration.
In SSM2007, the RHC and THC are simulated by the keyboard or joystick which allows the player to perform all On-Orbit duties.
the controls used are the Numpad keys.
the Numpad controls translations while the Arrows and the “Six Pack” control attitude.
|RHC (Attitude)||THC (Translations)|
|Pitch||NumPad8 / NumPad2||Forward/Aft||NumPad + / NumPad -|
|Roll||NumPad4 / NumPad6||Left/Right||NumPad / and NumPad *|
|Yaw||NumPad INS / NumPad DEL||Up/Down||NumPad9 / NumPad3|
Attitude control using a joystick is natural. Pitch, Roll are always available. YAW is usable if the joystick has a twist axis. Throttle if available should be kept in the middle of it's range (explanation in a second)
Translations with a stick are a bit more complex. to activate translations you hold down the Trigger while moving the stick around. Left, Right, Forward and Aft are available in this configuration.
Up/Down translations are controlled via the throttle. while holding down the trigger and “increasing” or “decreasing” the throttle the shuttle will translate up and down.
Some users find it easier to use the Stick for Attitude control, and the keyboard for translations.
The OMS Burns are the main Thrusters for changing orbit altitude and in some cases orbital inclination (small inclination changes due to the very high ΔV required).