currently in trying to establish a dependable setup/config for a trike gear (nosewheel) plane: takes of perfectly; landing a bit unpredictable yet.
HOWEVER, the plan is to transfer to a taildragger soon.
Pixhack V5, QGC. px4 1.8.2 stable
I have noticed a parameter that is set for pitch angle and mentions a taildragger situation:
RWTO_PSP (FLOAT) Pitch setpoint during taxi / before takeoff airspeed is reached. A taildragger with stearable wheel might need to pitch up a little to keep it’s wheel on the ground before airspeed to takeoff is reached 0.0 > 20.0 (0.5) 0.0 deg
im getting somewhat anxious about this. Has anyone flown a taildragger in RWTO mode yet, or auto landing?
ive flown taildragger planes manually for a few years now, and i’m worried that the parameter doesn’t indicate proper takeoff procedure…
- taildraggers need pitch up while airspeed is LOW to keep pressure on the rear wheel for steering. that includes taxi and BEGINNING takeoff. usually, this pitch is maximum since the propwash is it’s only pressure source, and the wheel needs to steer and battle adverse influence (wind, torque).
- During takeoff, Pitch is relaxed, usually steadily, as takeoff speed is increased. This is because the fin/rudder begins to affect steering AND to avoid premature liftoff and stall that happens if the pitch up remains. The plane gains speed at a level attitude until take off speed is reached, then pitch up is added again for liftoff.
Currently, i see only a single fixed opition for TO pitch. ?
setting this to level results in the wheel immediately lifting off as the propwash hits it, which usually means it goes sideways as the torque/wind affects the plane.
setting this to “pitch up a little” (usually) results in, predictably, the plane lifting off before it has sufficient speed for stable flight and stalls, drops a wing into the runway and crashes. The airframe behaves the same as a nosewheel plane, which is set to a neutral pitch (0deg?) until take off speed is reached and pitch up is applied for lift off.
what to do/think? anyone have experience with setting up PX4 for taildragger TO/landing?