On the 31st March 1916, at 21.45 hours, the L15 received a direct hit from the AA gun at Purfleet, Essex. The AA shell damaged four of the gas cells (numbers 9, 11, 12, and 16), and the L15 began to lose height - despite the crew chucking out everything, to lose weight. While the L15 got closer to earth, it was attacked by 2Lt Alfred de Bathe Brandon RFC, 19 RA Sqn (Hainault Farm), in a BE 2C. Brandon climbed above the L15 and tried to destroy it by dropping incendiary bombs, and Ranken darts onto the top of the hull. He was not successful, but eventually the Zeppelin became too heavy to fly, and she came down in the sea off Margate at 00.15 (1st April) - close to the Kentish Knock lightship.
The sodden, half-sunk remains of the L15 were then taken under tow but the airship broke up off Westgate and only small sections were hauled ashore, where parts were obviously liberated by souvenir hunters. Eventually the sea reclaimed what was left of the airship on the beach.