I came across this rather old but very interesting video of stall testing in the PC12 elsewhere. The pusher on/pusher off tests are an excellent example of why the type needs a stick pusher. Some of those post stall attitudes are pretty impressive!
Maybe this is why you dont practice ‘power-on stalls’ in a turbine aircraft!
Nice. I just found it odd for him to cancel torque with the aileron Don’t know if he was in full rudder, though. The behaviour of the aircraft was just as it should be.
Great aircraft. If it’d fit into my bank account …
I just found it odd for him to cancel torque with the aileron Don’t know if he was in full rudder, though. The behaviour of the aircraft was just as it should be.
Perhaps the pilot was trying to provoke spin entry with ailerons, to simulate the worst that poor pilot technique does in the type. Kicking rudder at the break would (obviously) provoke the roll-off even more, but in a PC12 I’d suppose that isn’t so likely an unintentional scenario.
“normal” is not what was stated. The statement was “as it should be”.
And could it be the issue was rather with pilot behaviour than with aircraft behaviour, anyway?
Not an expert, either, though.
@Silvaire, this may be the most obvious case, I think.
@Nestor, it depends on the control input. I have experienced power on stalls in a C150, resulting in a bad executed snap roll because of unexpected pilot inputs. In the video the pilot applies right aileron all the way at one point and then the plane reacts by rolling over the stalled wing. If he had applied right rudder, too, and neutralised it when he was overcorrecting with the aileron, this would be a perfect snap roll entry. In any case the left wing stalled completely and the right doesn’t. This means the plane keeps on rolling until either the right wing stalls, too, or both wings get unstalled. So it does, what it’s expected to do :-)
Remember that the aircraft is certificated with a pusher because it’s normal stall behaviour is “undesirable”. The dramatic stalls you see are without the pusher. Those with the pusher active are benign and straight ahead.
Thank you for posting. Given that it is a T-Tail it was good to see that after the un-commanded roll, recovery without a stick pusher was predictable.
this would be a perfect snap roll entry
…MH you would normally be applying some acceleration (typically 2G at basic/intermediate) for a snap roll entry; in the video they appear to be applying ‘normal’ stall entry, gently increasing back pressure close to 1G, reducing speed by a knot per second – which somewhat makes a lot of stall practice somewhat artificial.
The dramatic stalls you see are without the pusher. Those with the pusher active are benign and straight ahead.
But that’s because with the stick pusher there is no Stall in the first place. It simply pushes the nose down long before the wing stalls.
