Pilot error
Rules require air display pilots to pass a rigorous examination of their ability to fly chosen manoeuvres before they are issued with a Display Authorisation (DA). Pilots then create a “routine” with each stunt for which they are authorised, governed by a series of “gates” or points at which the plane will reach a certain speed, altitude and direction before starting the manoeuvre. Regulations stipulate that no aerobatics can be performed below a height of 500ft.
Aviation experts have suggested that the Hawker Hunter at Shoreham may have begun its loop the loop display at the wrong altitude, or its RAF veteran pilot Andy Hill mistook the horizon line on the adjacent Sussex coast. As a result the jet would have exited from its manoeuvre with too little height to recover level flight.
Mechanical failure
Despite being more than half a century old, the airframe of the Hawker Hunter is unlikely to be the direct cause of the crash. Like other vintage jets, the supersonic fighter will have been maintained to the highest standards and flown well within the limits for which it was designed. But it is possible the plane suffered a catastrophic mechanical fault during its aerobatics such as a “flame out”, where the jet’s engine simply stalls during the stunt and the pilot loses control. Shoreham plane crash - In pictures
Illness
The loop the loop-style manoeuvre performed by Mr Hill would have exerted significant g-force on his body. As a former RAF fast jet pilot he would have been used to such forces but he may have suffered a medical problem which caused a temporary blackout.
