Can ailerons control a broken cable on 1/3 flaps?

[Learjetter]

Originally Posted by JimC

I don't agree that it would work at higher airspeeds but not lower. The dynamic pressure would change on both the flap and the aileron as you slowed - so the single deployed flap would be producing less of a rolling moment as you slowed.

I also don't agree that "control-issue" approaches are always flown at higher airspeeds. It depends on the issue. For example, if I have a broken elevator control cable and I'm using trim to adjust pitch, why would I come in at a higher airspeed?

Jim, spot-on about the yaw.

As for the rest: I was speaking "generally"...not Skymaster-specifically. Wings are generally designed to stall at the tip first--as you increase AOA and slow, you normally lose control effectiveness in this order: aileron, elevator, rudder. As you decrease AOA and increase airspeed, you'll regain control in the opposite order. For this reason, as you slow for landing, if you have flight control issues (bound aileron, jammed elevator, iced-over/frozen rudder, etc) it's likely the POH recommends a higher airspeed to ensure the remaining flight controls are more effective. Skymaster POH may be different?

So, if there's a "stuck flap" and only one is in the wind, since it displaces more air than the smaller aileron, and is closer to the wing root, (and is therefore more effective since the wing is usually specifically bent or shaped to force a stall at the tip first) the flap will exert more rolling and yawing moment than the aileron at the same airspeed, I still contend that at lower airspeeds the flap will overpower the same displacement angle of aileron throw. How's that for a run-on sentence? (I'm on an iPhone...)

I'm willing to be wrong, as while my total time exceeds 4000 hours, my Skymaster time is less than .1% of that... Standing by for schooling...