August 15, 2016

The Helistat was a larger (343 ft to 302 ft) prototype built by the US Forest Service

between 1979 and 1986 (when it crashed and was destroyed.

http://www.nytimes.com/1986/07/02/nyregion/airship-crashes-at-base-in-jersey.html

AIRSHIP CRASHES AT BASE IN JERSEY

LAKEHURST, N.J., July 1— A nine-story-high experimental aircraft that combined four helicopters and a blimp crashed and disintegrated tonight during a test flight at the United States Naval Air Engineering Center here, killing one of five crew members.

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The craft is called a Helistat. Designed in particular to haul great loads of timber out of inaccessible virgin forests, it combined a 343-foot-long, one-million-cubic-foot Dacron bag – about five times the volume of a Goodyear blimp – and four old navy helicopters.

Forty-nine years ago, at the same Lakehurst air station, the hydrogen-filled German dirigible Hindenburg exploded only half a mile from the site of tonight’s accident. The Hindenburg disaster killed 36 people and brought to a close the short-lived era of transoceanic flight in lighter-than-air craft. Weight of 98,000 Pounds

In the craft that crashed tonight, the H-34 helicopters and the huge bag were attached to an aluminum superstructure about the size of a small bridge. While the bag and the rotors of the helicopters supplied lift, pusher propellers, one on each helicopter, gave the craft thrust. The Helistat weighed 98,000 pounds.

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”It’s a project funded by the U.S. Forest Service,” Ms. Grieco said, ”and they called on the Navy to monitor the engineering progress. It’s not a Navy project. The forest service was testing for the feasibility of using it for logging puposes in inaccessible areas.”

The United States Forest Service expected the Helistat to lift 25 tons of timber and Mr. Piasecki was investigating military uses. But the General Accounting Office, viewing the proposal dubiously, criticized the Government for spending $24 million on the project over the past six years

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