Why did the Hindenburg blimp explode?

The huge airship "Hindenburg", which was a symbol of Hitler's Germany, was built in the late 30-ies of the twentieth century. Its name was given to the aircraft in honor of the German Reichspresident. During its construction, special attention was paid to safety issues. So why did it explode in May 1937?

Explosion

On his last flight the airship "Hindenburg" set off on May 3, 1937. The cost of tickets was about 400 dollars. On board there were 97 people (together with crew members). In the gondola of the administration sat Captain Mark Pruss, who took part in the First World War. On May 6, an aircraft flew over Manhattan. Wanting to surprise the passengers, Pruss held a zeppelin next to the observation deck on the roof of the Empire State Building. The airship was so close that visitors to the site and passengers could wave each other. After circling slightly over the city, the Hindenburg blimp went to the base of Lakehurst for a planned landing and flew to the place by four o'clock. But from the west the stormy front was approaching, so the base commander, Charles Roosendaal, did not give permission to land. For two hours, Zeppelin flew along the coast in anticipation of news from Lakehurst. At six o'clock Pruss received a message from the base about improving the weather conditions and landing permission and took a course on it. At seven in the evening, another message came to Hindenburg with a recommendation to land as soon as possible. At 11 minutes of the eighth, Zeppelin fell to a mark of 180 meters. From the ground, the report about his arrival was led by Herbert Morisson, a famous American journalist. After 9 minutes the aircraft was balanced, then the mooring ropes were thrown off. Another 5 minutes later, in the stern area (just above the gas compartments), an ignition occurred, which spread to the nose for 15 seconds. There was a deafening explosion. 30 seconds after the fire, the Hindenburg blimp crashed near the mooring mast.

Sheathing

Zeppelin had a sheath of hardened cotton cloth impregnated with iron oxide with an admixture of aluminum powder and acetylcellulose butyrate. In theory, this should have provided the shell with both strength and fire retardant properties. But, using the substances that make up the airship paint, it was possible to create a termite mixture that ignites without access to oxygen. But this composition should burn very slowly, which completely does not correspond to the documentary video from the crash site.

The airship "Hindenburg" in a reduced form, painted with this mixture and placed in a hydrogen-filled environment, burned down in about a minute, not in a few seconds. As a result, experts came to the conclusion that the paint caught fire along with hydrogen. There were also such assumptions that termite paint is quite heavy for an airship and the probability of its use is very low. However, no one checked the degree of flammability of the material from which the aircraft itself was made . Therefore, the most likely reason is that the crash of the Hindenburg blimp occurred because of the flammable technical impregnation of the building material.