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Lockheed Brothers Aircraft (later Allan Lockheed Corporation - Alcor)


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Jan 28, 2008
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After Robert Gross bought out the ailing Lockheed Aircraft Company, there was no place found for Allan and Malcolm Lockheed in the new organisation. In 1930 Lockheed Brothers Aircraft Corporation (later the Allan Lockheed Corporation - became Alcor in 1937) was established. Malcolm helped financially and Allan led the organisation with Walter Diehl as designer and some hired aeronautical consultants.

Lockheed Brothers Olympic Duo-4

The first design was the Olympic Duo-4. It resembled the earlier Lockheed Vega but with a circular fuselage cross section and bigger. Construction was a one-piece wooden cantilever wing. Tthe fuselage was made with a conrete mould and vacuum bag technique use on the Vega. It was powered by two Menasco C-4 Pirates (275 hp each). The idea was to provide twin-engine reliability, minimising the risks of single-engine operations. The engine layout was unusual in that the pwerplants were on their side and spaced far enough apart to leave one foot (12 inches) of clearance between the two airscrews. It first flew on 18 March 1931 at Rosamund Dry Lake, California. Later it hit a parked vehicle at the Dry Lake and overturned.

Lockheed Brothers Olympic Duo-6

The remains of the Duo-4 was gradually rebuilt as the Olympic Duo-6. This aircraft was fitted with two Menasco Buccanear 6-cylinder engines. It was a similar configuration to the earlier example but with stronger spatted fixed landing gear which replaced the early flimsy looking gear. No market opportunities arose for the Duo-6. The aircraft crashed during a low-speed pass at Rosamund Dry Lake.

Alcor C.6.1 Junior Transport

In February 1937 a new six seat passenger aircraft was developed at Oakland Ca. by Alcor Aircraft Corporation. Designated the C.6.1 (Commercial transport 6 passengers, model 1), it was a wooden aircraft. the two Menasco engines were faired into the wings. The aircraft had retractable undercarriage. The retracted undercarrige together with the engines, again on their sides) gave the machine a sleek appearance. Again the propellers were only one foot apart. The cruising speed was 200 mph. Single engine performance was good with a single-engine flight ability at 12,000 feet. The first flight of NX15544 took place on 6 March 1938 flown by Mike Casserly. Soon after Eddie Allen was hired by Alcor for certification tests and subsequent marketing. the cost per example was just under $30K. On 27 June 1938, against Allan Lockheed's instructions, the aircraft was flown at 16,000 feet at over 300 mph. Aileron flutter arose and the aircraft broke up. Both crew baled out successfully. The aircraft crashed into San Francisco Bay.With the loss of the new feeder transport Allan Lockheed turned to selling land and property while giving aeronautical advise as a side-line.

Beyond The Horizons - The Lockheed Story (Thomas Dunne ISBN: 031224438X) by Walter J Boyne

Subsequently I have found and excellent coverage of these designs on William Pearce's Old Machine Press site http://oldmachinepress.wordpress.com/2013/10/18/alcor-duo-4-duo-6-and-c-6-1-transports/ complete with photographs!


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Jun 25, 2009
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If I'm not mistaken, at least one Olympic-Duo aircraft was produced under the name "Alhambra Airport & Air Transport Co.", although it's not clear how long that name lasted.


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May 6, 2007
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British Pathe newsreel footage of the Duo-6 (NX962Y) demonstrating its ability to fly on one engine.

YouTube - British Pathé - "Safety Plane Flies On One Engine (1930-1939)"

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