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.
