The Valley Bassett accident.
The cause of the accident is well documented. The then Station Commander was seriously injured and the Navigator, who was also a well known glider pilot in the RAFGSA world was sadly killed.
On the surface therefore, an "open and shut case" to hang the S.A.C involved in the refuelling.
The S.A.C however, wisely declined the services of his appointed officer, who would have been unlikely to risk his own career in the defence of an S.A.C anyway, and engaged one of m'learned friends.
The result was that m'learned friend subsequently proved that what is now referred to as systemic failure contributed to the accident and the S.A.C was acquitted.
The failures began at Station Flight, and progressed to the bowser pool which was located at the end of Gaydon Hangar at the time for the convenience of access to the Gnat Line.
I can't remember the exact findings but communication, the clarity of fuel markings on the bowsers / range of bowsers were closely scrutinised and shown to have been the causal factors, resulting in the S.A.C's error.
I understand that, as a result of the accident, changes were made as to the clarity of fuel markings on bowsers thereafter.