Originally Posted by
LOMCEVAK
BV, there is data supporting your assumption in the AAIB report. The aeroplane had to be flown at maximum instantaneous turn performance (light buffet) throughout the pull through to achieve that radius. Assuming that the aircraft was trimmed in pitch at the pull-up point, this would have required a significant (but easily applied) aft stick force and displacement throughout the manoeuvre. There are a couple of extra significant considerations.
First, analysis of the external videos showed that at some point in the manoeuvre the flaps were selected from 1 notch to 2.
Secondly, during the last quarter of the manoeuvre when about 30 degrees nose down the aircraft entered wing rock which would have been caused by a further aft stick input increasing angle of attack past the maximum value ie. the aircraft was pulled into an accelerated stall. This would actually have increased the height loss slightly but was, in my opinion, a totally instinctive control input and did indicate to me that the pilot was aware of the aircraft's flightpath with respect to the ground.
Your comparison with the Hawk is interesting because the Hunter is actually a lot easier to fly in situations such as this. It has a progressive increase in buffet intensity as AoA is increased compared to the Hawk as so is much easier for maintaining maximum instantaneous turn at all airspeeds.
There is also the fact that the Hawk behaves as a straight wing aeroplane whereas the Hunter a swept wing aeroplane, and therein lies the difference.
In a Hawk max CL comes as you achieve light buffet, pulling through this does not increase CL but actually reduces it, a straight wing characteristic. In the Hunter light buffet gives optimum CL for hard manoeuvring, but not max CL, that is achieved by continuing to pull into heavier buffet, ie wing rock, but with an unacceptable increase in drag, So, While you can get more out of the wing if you hold deeper buffet for any length of time, the loss of speed, ie energy, negates the CL advantage gained earlier.
To me this explains the wing rock In the last quarter of the loop and the fact that he didn’t tent peg. Whether or not AH was aware of this is irrelevant as most people put in this position would pull harder. Had he been in a Hawk and missed his gate height by a similar margin and not flown an escape manoeuvre he would have arrived at ground level in a steep dive, but the Hunter achieved a nose up attitude at impact albeit still descending.
He knew he was in the s.... and tried to do something about it !!! But decided not to eject.