SASless,
Great questions, here’s the current EP from the checklist:
Now, I haven’t personally experienced a stab failure where the stab slewed down in cruise flight, it’s either failed to slew(program) up on takeoff(stayed -40degrees) resulting in the nose dropping, or one time it slewed full up (+10degrees)and stayed full up on takeoff resulting in a nose high attitude.
Pilots I work with who have experienced a stab programming down at higher speed combined with reduced collective have indicated it is a sobering experience and the speed at which the nose tucks is quite rapid.
Another accident in Egypt was caused by a stab that was repeatedly failing out of auto mode but they kept flying, manually controlling the stab. Then they did an airspeed over altitude takeoff from a cliff side LZ, where people liked to “dive” over the side of the cliff, the stab was still failed full down, resulting in a crash into said cliff face.
I certainly hope that nobody was messing with manual control STAB switch, there have been too many accidents due to that sort of thing.