Originally Posted by
Bergerie1
Centaurus,
The 'yo-yo' manoeuvre you describe was the same for the 707. I never had to do it for real, only in the simulator. But I have heard, at second hand, of a crew who had a runaway stabiliser and who used that method to restore normal trim. I understand it was exceedingly hard work. And stressful, as it was done at low altitude over Toronto, but they saved the day.
Folks,
I don't know where this comes from, but with a jammed/frozen stab on the B707, you simply trimmed by splitting the spoilers, and at lower speed, splitting the flaps ---- one of the lesser advertised benefits of a swept wing.
There was no need for any so called "yo-yo" maneuver.
It is true of the B707 that full elevator deflection could stall the stab, and you had to reduce the aerodynamic load on the stab by reducing the elevator deflection, which you wouldn't want to do close to the ground, if it meant lowering the nose.
So: On the overhead panel, about the Captain's right eyebrow, Spoiler Switch UP, and pull the Speedbrake as required. The rule was:
Switch UP, pitch Up, Switch Down, pitch Down ( except on G- registered aircraft, where D.P.Davies buggered it up, as usual).
I will be fascinated to find out what the real problem is with the speed stability system on the Max --- anybody who flew them cast your minds back to the A310 and A300-600, and aircraft losses.
Tootle pip!!