Harmon Der Donnerschlag Explained

The Harmon Der Donnerschlag (English: Thunderclap) is an American homebuilt aircraft that was designed and produced by Harmon Engineering of Howe, Texas. The aircraft was intended for amateur construction.^[1]

Design and development

Der Donnerschlag features a wire-braced shoulder-wing, a single-seat open cockpit, fixed landing gear and a single engine in tractor configuration.

The aircraft's 19.51NaN1 span wing has two beam-type spars and employs a 16% airfoil at the wing root, tapering to a 12% airfoil at the wingtip. The standard engine used is the 750NaN0 Volkswagen air-cooled engine automotive conversion, driving a two-bladed wooden propeller.^[2]

The aircraft has an empty weight of 350lb and a gross weight of 600lb, giving a useful load of 250lb. With full fuel of the payload is 190lb.

The aircraft was later developed into the Harmon Mister America.

Operational history

By October 2013 there were no examples registered in the United States with the Federal Aviation Administration and none may exist anymore.^[3]

Notes and References

1. Plane and Pilot: 1978 Aircraft Directory, page 142-143. Werner & Werner Corp, Santa Monica CA, 1977.
2. Web site: The Incomplete Guide to Airfoil Usage. 10 October 2013. Lednicer. David. 2010. https://web.archive.org/web/20100420012244/http://www.ae.illinois.edu/m-selig/ads/aircraft.html. 20 April 2010. dead.
3. Web site: Make / Model Inquiry Results. 10 October 2013. Federal Aviation Administration. 10 October 2013.