Nothing to do with the Ambassador but a similar bracket of test flying.
The Aerospatiale S330 Puma was being flight qualified in the mid sixties. The Puma had been fitted with a flight stabilisation system that made it fly very much like a fixed wing aircraft. The test series were to assess what problems would arise at the extremities of the performance envelope should part of the stabilisation system fail.
One of the tests was to fly it at VNE (velocity never exceed) and have a full runaway of the yaw (tail rotor) control channel at the aft limit of the CofG. For those who are unfamiliar with helicopters the three control planes can effect each other in much the same way as a fixed wing.
The helicopter would be set up in a dive as it was the only way of achieving VNE and a switch would be thrown which would put the tail rotor actuator into open loop. The tail rotor would immediately run to full pitch and violently slew the aircraft and induce roll.
The pilots would then have to wait for two seconds before taking corrective action.
The roll rate induced was something in the order of 90-100 degrees/second. The general consensus was to let go all the way round but they had to prove that a normal commercial pilot could bring it back; and they did, and it passed.
Last edited by Fareastdriver; 14th Jul 2017 at 21:20.