In September 1943, even before the XP-80 had made its first flight, Lockheed had proposed a larger and heavier L-141 version powered by the more powerful General Electric I-40 "Whittle" turbojet engine (later produced by both General Electric and Allison as the J33). The USAAF was sufficiently impressed that they issued a contract for two examples under the designation XP-80A. Serials were 44-83021 and 44-83022.
The General Electric I-40 engine that powered the XP-80A had a thrust of 4000 pounds, and was fed by intakes relocated a bit further aft to a position just below the cockpit windshield. The XP-80A was significantly larger and about 25 percent heavier than the XP-80 prototype in order to accommodate the larger engine. The wingspan was 39 feet 0 inches, two feet greater than that of the XP-80, but wing area was reduced to 237.6 square feet by using a narrower chord. Length was increased from 32 feet 10 inches to 34 feet 6 inches. Height increased to 11 feet 4 inches. Weights were considerably greater than those of the XP-80, being 7225 pounds empty, 9600 pounds gross, and 13,780 pounds maximum takeoff. The increased weight required a stronger undercarriage. Ammunition capacity increased from 200 to 300 rounds per gun, and internal fuel capacity increased from 285 to 485 US gallons. In contrast to the XP-80, the XP-80A was fitted with a pressurized cockpit.
XP-80A 44-83021 flew for the first time on June 10, 1944. It was followed on August 1 by XP-80A 44-83022. 44-83022 was fitted with a second seat which could carry an engineering observer. Early in the test program the XP-80A experienced excessively-high cockpit temperatures due to a faulty cabin pressurization valve. This problem was easily fixed, but there were more serious problems encountered with an unstable airflow through the intake ducts. Kelly Johnson took a ride in the rear seat of 44-83022 in order to try and figure out what was causing the problem. Kelly Johnson was an extremely talented aeronautical engineer, and he correctly diagnosed the cause as being boundary layer separation along the walls of the duct. The problem was solved by adding a series of boundary layer bleeds along the upper edges of the ducts. This feature was added to all subsequent production aircraft.
The second XP-80A became the first in the Shooting Star series to carry a 165 US-gallon drop tank underneath each wingtip. When carried, these tanks actually lowered rather than increased the drag. They could be brought home empty with no penalty in aerodynamic drag. The tanks also improved aileron effectiveness and wing loading.
The first XP-80A crashed after an engine failure on March 20, 1945, but test pilot Tony LeVier managed to parachute to safety and escaped with only back injuries. The second XP-80A was later used as a testbed for the Westinghouse J34 axial-flow turbojet in support of the XP-90 program.
44-83021/83022 Lockheed XP-80A Shooting Star c/n 141-1001/1002 83021 crashed March 20, 1945. Pilot Tony LeVier parachuted to safety.