There is a
rumour that his parachute failed to open.
The link posts to what appears to be the correct page but appears o have had the following text removed:
MoD said that the pilot had died from multiple injuries sustained during the accident in which he was ejected from the cockpit while the jet was still on the ground.(This part included by myself to indicate the location of the missing text)
According to one local report, the pilot's parachute failed to deploy after being ejected from the seat.