Inverted flight

[max_newbie]

Hey guys, im new here, just tried this package last night. I've been playing with the gliders, however noticed something funy. When flying inverted, the rudder controls do not invert, thus steering left will still steer left. At least, on my XP system when using the keyboard (I dont have a remote setup). Is this a bug or something that has been overlooked?

Anyhow, nice work.

[lego]

Hmm - when I fly inverted in reality (upside-down), then rolling to the right is still done by movin the stick to the right, because the rollmanuver isn't influenced. The only thing that is inverted are the elevators!!!

So FMS is absolutely correct!

[max_newbie]

As much as I keep replaying this in my head.. I still can't see how the rudder will not reverse the process, though the elevators do.

[lego]

[Divit]

I think rudder and ailerons are being confused a bit here. The glider you are flying probably has ailerons and you are probably using them to steer (thinking they are the rudder.). Ailerons as they affect the roll axis do not reverse when inverted as has already been stated. I'd check your setup (key assignments)

Rudder effects the yaw axis. As left and right rudder are constant relative to the top of the plane it reverses when inverted, as does the elevator (also constant relative to the top of the plane.)

Just to clarify, the function of the rudder does is not to control roll. Any rolling and/or banking that the rudder induces is strictly a function of dihedral (in the FMS model's par file anyway) and several other factors in real life. For instance some aircraft (particularly trainers and gliders) can use the rudder to make banked turns (in fact some only use rudder as in a 2 or 3 channel setup with no ailerons). As the plane yaws (tail swings sideways) the plane will begin to roll and some will indeed roll all the way around. This is due to other factors desiged into the plane only (dihedral, surface positioning, etc). Other aircraft like a well designed pattern plane will turn flat with rudder only. No rolling motion whatsoever. All banking and rolling is done with the ailerons. These aircraft are said to be neutral and have no coupling. In other words each control only affects the axis it is intended to. Rudder=yaw, elevator=pitch, ailerons=roll. That is why on a glider for instance, it can be difficult sometimes to distinguish between rudder and aileron when you are flying.

hope that helps.

[FlyingWingNut]

Many of the jets that fly in FMS have swept back wings. A swept back wing behaves like dihedral in that it converts a sideslip into a roll. Hence left rudder; left roll. But it is like variable diheral. When flying fast with a low CsubL the dihedral effect is much smaller. When the plane has no lift there is no dihedral effect and when inverted it is dihedral going the other way. That means when you are upside down flying a swept wing, the dihedral effect is bent toward the landing gear and left rudder now causes right roll.
None of the swept models I've flown in FMS behave that way. They act like fixed dihedral. Does anyone know if the parameter files allow correct flying characteristics for a swept wing flying upside down?

[FlyingWingNut]

Many of the jets that fly in FMS have swept back wings. A swept back wing behaves like dihedral in that it converts a sideslip into a roll. Hence left rudder; left roll. But it is like variable diheral. When flying fast with a low CsubL the dihedral effect is much smaller. When the plane has no lift there is no dihedral effect and when inverted it is dihedral going the other way. That means when you are upside down flying a swept wing, the dihedral effect is bent toward the landing gear and left rudder now causes right roll.
None of the swept models I've flown in FMS behave that way. They act like fixed dihedral. Does anyone know if the parameter files allow correct flying characteristics for a swept wing flying upside down?

[ggunners]