On 13 July 1910, a partly cloudy day, the airship Erbslöh crashed near Pattscheid (today a quarter of Leverkusen). The cause that was accepted by the subsequent investigation committee was: a sudden exposure of the envelope to the sun after the ship had been flying under cloud cover and cool morning fog. When the lifting gas was thus heated, it began to expand. The relief valves could not divert the developing excess pressure inside the envelope fast enough, so that the valves were overwhelmed. This allowed hydrogen lifting gas to come into contact with sparks from the propulsion system, causing the gas to explode. The burning ship fell down out of the air.