I was watching this program on one of the major learning channels and they did a program on the Hindenburg. Well according to the investigator what might have happened is pilot errors.
The idea is that the zeppelin design used tension cables as part of the internal structure, not uncommon but in high wind using full control input it puts stress on the rear sections. So the captain trying to land in high wind to keep on scedule made heavy control inputs and one of the internal cables snapped and opened a gas bag. Now there was a light rain and they dropped a rope tied off to the struture and the rope being wet with rain hits the ground. Well this zepp has been flying around collecting all kinds of static for days and now all of the static in the skeliton snaps to the ground through the rope. The static does not discharge from the skin though and the charged skin being close to the now neutral skeleton and then finally the skin discharges and creates a spark. This inturn ignites the free hydrogen and it burns off to the bag, the first bag goes up and then the whole thing goes up. Well they knew about the weakness in the back under full control inputs and wrote in the POH not to do it. Therefore Pilot Error.
Lessons that should have been learned:
1. Dont use full control inputs where the POH says not to.
2. Hydrogen is not a proper gas for AirShips!
Anyway being a fan of large rigid airships its nice to have a pretty good explination of what happened to something that could have been a pretty cool thing.