One or both of the rear ballonet air relief valves remained in an open position for undetermined reasons, which caused an out-of-balance trim condition; also causal was the flight crew’s decision to the fly the airship with a known deficiency (the inoperative ballonet indicator) and the pilot’s failure to follow proper emergency procedures.

The ground crew's diverted attention toward the landing airship while trying to catch a mooring rope, which resulted in their failure to detect an immenient collision with each other.