https://www.atsb.gov.au/media/5226668/199003089.pdf
A newspaper report last week covered an interview with the relatives of the deceased of a Kingair crash at Wondai Queensland in 1990. It was the 30th anniversary of the crash. Wondering what happened I pulled up the ATSB report. See above link.
In short, it was a dark night takeoff. The aircraft was airborne for only a few seconds and flew into the ground wings level and exploded. It was a private flight.
The report suspected the pilot may have been a victim of somatogrovic illusion. While that may never be known, the following extract from the report is worth study if only because it comes up with interesting figures in terms of acceleration rates versus pitch-up angles.
Quote:1.17.4 The somatogrovic illusion
Under acceleration, the combination of gravity and the inertial forces produce a resultant force at an angle aft of the true vertical. Acting upon the human vestibular system, and in particular the semi-circular canals of the human inner ear, such forces can, in conditions of reduced or no visibility, give a pilot a false pitch up sensation.
That is, while the aircraft and pilot may be flying straight and level or climbing slightly, the pilot may have the sensation of climbing at a much steeper angle than they in fact are. Without some visual input to override this false sensation, the pilot will usually react to it as a real and accurate perception of his/her position and travel in space. The normal response to this situation is for the pilot to gradually push the nose of the aircraft down, resulting in the aircraft descending. This phenomenon is known as the somatogravic illusion.
The somatogravic illusion has been linked with a large number of accidents in which aircraft impacted unlit terrain under control shortly after take-off on dark nights. Although the illusion is generally associated with high performance military aircraft, it can arise in lower performance aircraft. For example, an aircraft accelerating from 100 to 130 knots in 10 seconds generates an acceleration on the pilot of 0.16 G, which is sufficient to produce the sensation of a 9 degree pitch-up.
Accident studies indicate that long pilot experience is no certain protection against "dark night take-off accidents". Pilots with limited recent night or instrument flying experience appear more susceptible to spatial disorientation, possibly because they may not be fully accustomed to (misleading) acceleration sensations. The level of recency may also affect instrument scan technique.
Calculations showed that VH-LFH accelerated at an average rate of 8.79 feet/second/second (0.275 Gs) from lift-off to impact. This would have been sufficient to produce the sensation to the pilot of a pitch-up of about 15.3 degrees.
Unquote. (My bolding in red)
Kingair pilots might find this useful info as well as flying instructors teaching night VFR. 15 degrees pitch up happens to be an average climb attitude for jet transports after lift-off. I had no idea that a somatogrovic illusion could be that severe.