Originally Posted by
DogTailRed2
The L29 seems to have suffered quite a few accidents over the years in civilian use.
Suffering the same fate as the Hunter perhaps. Fast ship in the wrong hands?
Pilots have very likely missed or failed to compute the "enegy gates" to execute the maneuver. I dont know what they intended to do, if it was a barrel roll ( probably not as they interrupted it while inverted unless they were disoriented or incapacitated) or more likely a reverse cuban 8 ( Pull to 45 degrees up pause then pull through then level off) .
For a normal roll even with the "pause" while inverted would have been a non event, they would have ended up upright though nose low with plenty of height available, they had plenty of energy available after that high speed low pass.
But -and here lies the risk- with this same energy to spare on the reverse cuban 8 after inverted the "energy gate" was busted: way too low and fast. Closing that portion of the loop while inverted was impossible, the radius arc ( It increases at the square of the velocity, double the speed quadruple the radius) was too large and there was not enough room to allow for it other than stall under g while pulling to avoid hitting the ground.
When "energy gates" are not considered in advance, any non compliance or improvisation is a big risk, then the maneuver should be aborted; From inverted complete the half roll and recover straight and level. You may well have luck in a light aerobatic Extra aircraft with his quick roll rate and ligher wing loading, but no chance on a heavy underpowered military jet trainer.
The laws of physics are non negotiable. Speed and height did not permit that closure of the maneuver. It should have been aborted.
There is a similar, very similar incident of an italian eurofighter which hit the sea in the same fashion,in Pratica di Mare some years ago, just google for it.
It was much higher that this L29 probably in excess of 10'000 feet but with much higher closing speed it 3-400 knots I would assume, the radius to close the maneuver was immense, and while pulling out agressively with the sea appraching the Eurofighter stalled under heavy G and pancaked, The L29 likewise stalled dropped a wing and flipped.
More than" fast ship in the wrong hands", fast ship without proper training and improvisation.