Cheese Holes 101:
1. The crash was probably caused by adverse environmental/operating conditions exceeding the pilots ability to maintain effective control of the aircraft.
2. The incapacitation of the pax was caused by an inadequate/inappropriate restraint system during operations.
3. The fire was caused by the failure of a device only intended for use following a rollover and hence never used or apparently tested.
4. The deaths of the pax was a combination of 2 and 3.
Pax restraint on Ops is always a bone of contention, nobody expects to be fully strapped in when they are expecting to be leaping out at any moment. A fully functional restraint system for fully fitted troops has yet to be devised. This is an operational risk.
The spill valve check was either a scheduled maint check or not - if it had been checked previously and been found serviceable it was an equipment failure, if it hadn't been checked, but should have been according to the servicing schedule, it was a failure of the maintenance organisation.
This appears to be a classic case where operational pressures conspired to place the crew and pax in a situation that ended tragically. The aircraft handling in the operating conditions, the pax restraints, the spill valve and the fire all taken as single events probably would not have been fatal, but on the day where the professional ethos of getting the job done placed these events into an inescapable series of disasters, a tragedy ensued.
So once again, a layman with a bully pulpit thinks its his duty to publicly "name and shame" those whose professionalism and committment to public duty is beyond compare. On the day it all went wrong, but nobody conspired to set those events in motion, neither the pilot, the engineers, the designers, or the RAF. By all means let's learn from this but get off the "conspiracy of incompetence" hobby horse.