A quick summary...
The 3 semicircular canals in the human ear cannot differentiate between acceleration in the forward plane and a pitch upwards with no visual input. (this is how flight sims work). Think about it - the fluids slosh rearwards (to the back of the head) in both instances.
After takeoff on a dark night for example, you start to accelerate away from ground effect, or lowering the nose to a climbing speed. This speed increase may be percieved as a pitch up without any external visual cues (and without an instrument scan).
The pilot's natural fear of stalling leads him or her to pitch down, further increasing the speed and the pitch up perception, so push the stick forward etc etc until impact.
It is important to note that a lack of visual cues (and often a lightly loaded aircraft which will perform well) are essential to this illusion...dark night bush takeoffs are a prime candidate.
BASI did an excellent report 8? years ago on a KingAir which smacked in 6ish nm from the runway under full power one dark night somewhere in Queensland. Maybe others can enlighten us to the occurrence report.
By God I actually remember something useful from ATPL!
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Those who restrain desire do so because theirs is weak enough to be restrained.
William Blake