Originally Posted by
Pilot DAR
I'm not sure I accept that the fatal crash force was "between 3 g and 4.25 g." (page 27 of the AAIB report), I expect a much higher number for a .45 to .75 stop from 55 MIAS? My very modest search for a calculation result suggests as high as 65 G. A friend of mine similarly crashed his 150, similarly stopping in about 12 inches, near straight down. The coroner told me that his stop was in the range of 200 G.
In any case, a nose down vertical arrival will likely be fatal, regardless of seatbelt use.
I also found the stated figures for decelerative g force to be unbelievable.
An object dropping from 50' (15m) arrives at Earth with a vertical velocity of 17ish m/s, or 40 mph. If stopped in 1 metre, that represents a deceleration of 150 m / s ^ 2, or 15g, in round numbers. Stopping in under 1m causes proportionately higher deceleration. The stated figure of 3 or 4g just doesn't make sense. 30 to 40g would be more accurate approximations.