The latest report says it started when an electrical storm caused the Hindenburg to become charged with static electricity.
Add to that a hydrogen leak that allowed the highly explosive gas to build up in ventilation n shafts.
The final key was when the ground crew grabbed the ropes used to help the zeppelin land. That completed a process called earthing. It connected the Hindenburg to the ground and caused the spark that led to the explosion.
The team has been experimenting on 79 foot scale models for several years before coming up with the final report.
The Hindenburg was destroyed as it landed on May 6, 1937 killing 35 people.
Interestingly, the airship industry may be making a comeback due to new technology and materials. Bloomberg reports some manufacturers believe the ships may steal away business for travel and cargo by 2016.