H-class blimp

The H-class blimp was a small observation airship built in the United States for the U.S. Navy in the early 1920s. The design dated from 1919 and called for a twin-engined envelope of about 80,000 cubic feet, shaped by a proposal from Commander Lewis Maxfield that a small airship could serve as a tethered kite balloon, or be towed by a ship and then cast off to scout on its own. As built, the type had one 60 horsepower Lawrence L-4 engine, a crew of two and a top speed of about 80 km/h. The first example, H-1, was tested at the Wingfoot Lake airship hangar and shipped to Rockaway, where it flew six times in the summer of 1921 before a hard landing threw its crew out of the control car. It drifted away, deflated overnight and was later destroyed in the Rockaway hangar fire of 31 August 1921. A second H-type, supplied to the U.S. Army as the OB-1, was damaged in October 1923 and declared surplus at the end of that year.