As its name suggests, the Electra Junior is a scaled down version of the Lockheed 10 Electra, the company's first all-metal aircraft. Designed from the outset to appeal both to private pilots and to airlines, development was accelerated to meet the 30 June 1936 deadline imposed by the Bureau of Air Commerce in its competition for a small and quick feeder-liner. The 12 made its first flight with just three days to spare, symbolically at 12:12. Despite winning the competition, the aircraft was not economically suited to the feeder-liner role and the overwhelming majority of sales were to corporate and private customers.
First flight: 27 Jun 36 (c/n 1201, NX16052)
Production: 130, at Burbank, CA.
First delivery: 5 Sep 36, to Tela Railroad Co. (c/n 1202, NC16076)
Last delivery: 13 May 42, to Royal Netherlands Indies Army (c/n 1314, L2-46)
Variants: 12-A - prototype and initial production version, powered by 2 Pratt & Whitney Wasp SB Jr. radials, with seating for up to 6 passengers in either luxury or airliner layout (the latter with toilet) (74 built; 10 impressed as UC-40D);
12-B - 12-A for Argentine Army, powered by Wright R-975-E3d Whirlwinds (2 built);
12-25 - 12-A powered by Wasp SB3 Jrs (2 built);
C-40A - staff transport for the US Army Air Corps, powered by R-985-17 Wasp Jrs (10 built);
C-40B - experimental aircraft with fixed tricycle undercarriage (1 built, converted to C-40A);
JO-1 - staff transport version of 12-A for US Naval Attaché in Brazil (1 built);
JO-2 - staff transport for US Navy and Marine Corps, powered by R-985-48 Wasp Jrs (5 built);
XJO-3 - experimental aircraft for use in assessing suitability for carrier-based operations with fixed tricycle undercarriage (1 built);
212 - armed version for training bomber crews for the Royal Netherlands Indies Army, equipped with .303 machine gun in dorsal turret, a nose-mounted fixed forward facing machine gun of the same calibre, and under-fuselage racks for up to 8 100-lb bombs; powered by R-985AN-4s (16 built);
12-26 - unarmed transport version of 212 for both civil and military use by Netherlands East Indies Government (20 built).