According to the UK Air Accident Investigation Branch’s interim factual report on the Shoreham air show crash, nothing detectable was wrong with the Hawker Hunter at any point in the display.
It has been confirmed that the aircraft entered the fatal vertical manoeuvre at a height of 200ft when 500ft would have been the normal minimum – and certainly wiser – thus leaving very little room for misjudgement in a trajectory that is frighteningly easy to get wrong, even for a skillful and experienced pilot.
The intent in a normal vertical manoeuvre like this loop-with-roll would be to complete it at the entry height, but certainly not less when the aircraft began the manoeuvre close to the ground. In fact the aircraft began to pull up from 200ft above ground level and finished by impacting the surface.
There may yet be more to this story than the AAIB has just revealed, but there were cameras and a microphone in the cockpit which should confirm most of what it is possible to know.
Air displays contain risk, like Formula 1 and other sports do. If they didn’t, nobody would go to watch them. But they are not intended to extend the risk to non-participants. That is the part that needs examination.