So this is what caused it all?
We saw a little bit of blue fire just forward of the vertical rudder, the upper rudder. It hung right to the top ridge,” he said. In a documentary being broadcast on Channel 4 on Thursday, experts reveal the sequence of events that triggered the explosion.
The airship had become charged with static as a result of an electrical storm. A broken wire or sticking gas valve leaked hydrogen into the ventilation shafts, and when ground crew members ran to take the landing ropes they effectively “earthed” the airship.
The fire appeared on the tail of the airship, igniting the leaking hydrogen.
“I think the most likely mechanism for providing the spark is electrostatic,” Stansfield said.
“That starts at the top, then the flames from our experiments would’ve probably tracked down to the centre. With an explosive mixture of gas, that gave the whoomph when it got to the bottom,” he said.