Investigation Summary
The L-2 was undergoing acceptance trials to become the flagship of Germany's new aerial fleet. During the morning of the flight, solar heat caused the hydrogen gas within the bags to expand while the airship was still on the ground. Once released, the L-2 rapidly rose to approximately 610 metres (2,000 feet). To prevent the gas bags from rupturing due to the increasing pressure, the crew vented hydrogen through relief valves. Due to a design flaw, these valves were located too close to the engine cars; the vented gas was sucked into the forward engine's intake and detonated. This initial hydrogen fire quickly spread, leading to a series of heavy detonations as the gasoline (benzine) tanks exploded. The airship was enveloped in flames and plummeted. The explosion was powerful enough to blow passengers from the center gondola through the sides of the car, with their bodies discovered a distance from the main wreckage site. The structural remains consisted of a mass of crumpled aluminum and twisted debris.
Final Conclusions
The disaster was caused by a design flaw where hydrogen relief valves were positioned too close to the engine intakes. Vented gas was sucked into the forward engine and ignited, leading to a catastrophic fire and the subsequent explosion of the gasoline tanks. The loss of the L-2, occurring just one month after the L-1 disaster, forced a total redesign of the Zeppelin ventilation and valve systems to ensure hydrogen could not accumulate near ignition sources.
Photographic Evidence (1)
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Systems & Failure Modes
Gasoline Tank
The fuel storage system for the internal combustion engines; a leak or vapor ignition led to the primary explosion.
Aluminum Structure
The rigid framework of the Zeppelin, which collapsed into a mass of twisted metal upon impact.
Interesting Facts
- 01The airship was a Zeppelin LZ 18, designated L-2 by the German Navy.
- 02The accident occurred after hydrogen gas vented from relief valves was sucked into the forward engine intake.
- 03The victims included seven officers of the admiralty trial board, including Commander Behnisch and Lieutenant Freyer.
- 04The pilot was Captain Gluth (sometimes cited as Glund), a long-time employee of the Zeppelin Company.
- 05The airship had completed only 10 flights totaling 34 hours and 16 minutes of flight time prior to the accident.
- 06The explosion was so violent that bodies from the center gondola were found a quarter mile (400 metres) from the main wreck.
- 07Naval Constructors Neumann and Pietzker were among the high-ranking officials killed in the disaster.
Safety Actions & Advisories
Design Redesign
Following the investigation, Zeppelin airships were redesigned to move relief valves further away from engine cars and improve ventilation within the hull structure to prevent the accumulation of diffused hydrogen gas.