M-class blimp

The M-class blimp was a large United States Navy patrol airship built by the Goodyear Aircraft Company of Akron, Ohio as the follow-on to the K-class anti-submarine blimp. It was about 50 percent bigger than the K-ship, because operations in tropical regions had shown that a larger envelope was needed to offset the loss of lift in hot air. The Navy ordered a prototype in August 1943 and then 21 airships, but cut the order to four, M-1 to M-4, which were delivered in February to April 1944. Each was roughly 300 feet long with a very long, three-section control car and two Pratt and Whitney radial engines. The M-class ships left service by 1956, and Goodyear went on to design the still larger N-class in the 1950s.