The BAe one where the engine quit was down to a faulty assembled unit if I remember correctly, not negative G as the cause..
From the AAIB report:
Summary and discussion
The investigation established that the accident resulted from a loss of control of the aircraft associated with a temporary loss of power from the left engine. The nature of the accident site, plus the high degree of fragmentation of the wreckage meant that some potentially useful items, such as the fuel filters and the left engine propeller control unit, were not recovered. Thus,although the possibility of fuel line or fuel filter blockage could not be ruled out, such an event would more probably manifest itself at higher fuel flows, such as during take off or climb to altitude. A PCU
malfunction may have caused the observed RPM excursion of the left-hand propeller close to the apex of the final wing over, but it is unlikely this would have resulted in an immediate power reduction to the observed extent indicated by the left yaw.