I have modified the flight model to be more like a spacecraft than an airplane, complete with thrust vectoring and enough power to put into space and bring it back down (Engine power is no longer dependent on altitude and has less spool time). I have even added automated retro thrusters that will slow the ship to zero airspeed so that landing vertically is possible. I have run into a few roadblocks that keep me from finishing it, however.
- External reactions in JSBSim seem to crash Outerra, so I can't use this section to simulate retro thrusters or the vertical thrusters.
- I can't figure out how to control different engine powers. The generic value is fcs/throttle-cmd-norm, which is your throttle input from 0.0 to 1.0 and gets applied to every engine equally.
- We can't assign multiple axes to different engine controls anyway, so the differing control levels of all engines would have to be automatic.
- Controlling this thing in upper atmosphere and space is very difficult as just very small vector thrusts will send this thing into uncontrollable spins. Currently I am just scaling back the control authority based on engine power and air density to a lower limit, which makes for smoother controls in the thinner air and when engine power is higher. However, all corrections still have to be made manually. I would like to be able to automate a stabilizer using the various vertical and horizontal thrusters, so that when you let go of the control, it will stop its spinning.
- Also, directional control from control surfaces is non existent on this ship, since it does not have a rudder. I am assuming that that is controlled with differing the engine powers on the left and right sides to force a yawing moment.
Also, has anyone checked the scale of the ship? It seems a little big to me. Looking up the specs, the length should be 30.5m, width is 23.3m, and the height is 10m.