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Lockheed Electra


[top] Photo Gallery



The Lockheed Electra shown here was of the same vintage as the Douglas DC-2, DC-3 series, but was smaller and carried only about ten passengers. Amelia Earhart was flying an Electra when she was lost in the Pacific in 1937. Circa 1936.

June 1937

This image shows Earhart standing in front of the Lockheed Electra in which she disappeared in July 1937. (article).



The Lockheed 12A Electra Junior was delivered from the factory had only the fins mounted at the tips of the horizontal tail. Langley tried a center fin to improve the directional stability of its Lockheed 12A Electra Junior executive transport in June 1940. The Electra Junior was also equipped with wing de-icing using engine exhaust. The latter modification resulted in 'NACA 97' becoming one of the first aircraft assigned to the newly-opened Ames Aeronautical Laboratory in California. The center fin was removed at the time the aircraft was sold in order to comply with the approved type of certificate for the aircraft.


Lockheed 12A Electra Junior: Langley tried a center fin to improve the directional stability of its Lockheed 12A Electra Junior executive transport. NACA test pilot Mel Gough stands nearby.

[top] Whirl Flutter Testing

Model tested in the 1/15-scale model of the Full-Scale Tunnel. The Electra model, now part of the Langley Archives Collection (Box #19), was built at home by Bill Reed.


Sting-mounted propeller whirl model testing

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Testing for the Electra L-188 was also conducted in the Transonic Dynamics Tunnel. It was the first testing conducted after the remodel, changing the tunnel from the 19-Foot Pressure Tunnel to the 16-Foot Transonic Dynamics Tunnel. On Sept. 29, 1959, Braniff Flight 542, a new Lockheed L-188 Electra Turboprop, fell out of the sky killing all 29 passengers and five crew members. On March 17, 1960, a Lockheed L-188 Electra crashed into a field. All 63 people on board died. Again, Bill Reed was involved with the testing. For more, see

50 Years at the TDT: Reflections and Predictions

50 Years Ago: Tests in a New NASA Wind Tunnel Help Save an Industry

Whirl Flutter Demonstration Model. Letter from Wilmer 'Bill' Reed concerning the rationale of building the model and testing.

[top] Technical Reports

An Analytical Treatment of Aircraft Propeller Precession Instability. W. H. Reed and S. R. Bland. 1961. TN D-659. An analytical investigation of precession-type instability.

Propeller - Nacelle Whirl Flutter. J. C. Houbolt and W. H. Reed. Journal of Aerospace Sciences, Vol. 29. 1962.

Propeller Whirl Flutter Considerations for V/STOL Aircraft. W. H. Reed and R. M. Bennett. CAL/TRECOM Symposium. 1963. Propeller whirl flutter considerations peculiar to v/stol aircraft and the related problem of response of propeller-nacelle system.

Propeller - Rotor Whirl Flutter: A State-of-the-Art Review. W. H. Reed. 1965. TM-X-56678. Propeller rotor whirl flutter and instability in conventional and Vertical Takeoff and Landing.

Propeller-Rotor Whirl Flutter: A State-of-the-Art Review. W. H. Reed. Journal of Sound Vibration, Vol. 4. 1966. Propeller-rotor whirl flutter and effect of hinged blades and flexible twisted blades.

Review of Propeller - Rotor Whirl Flutter. W. H. Reed. 1967. TR R-264. Survey of propeller rotor whirl flutter.

Aeroelasticity Matters: Some Reflections on Two Decades of Testing in the NASA Langley Transdynamics Tunnel. W. H. Reed. 1981. TM-83210.

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