The Lockheed P-38 Lightning is a twin-engined fighter aircraft designed for the USAAF, finally, one of the most iconic aircraft of World War II. Amidst all its brilliant virtues, there is an interesting omission of the P-38 from the RAF inventory. This omission sets up questions about the operational record of the aircraft and its comparative performance with other fighters of its time.
The P-38 journey began with the first USAAF order AC-13205 for 80 aircraft placed on September 16, 1939, and production resulted in the P-38, XP-38A, and P-38D variants. Successive orders developed the P-38 family into the P-38E, P-38F, and P-38G variants. Before the second USAAF order, an Anglo-French order for 667 aircraft was placed, which were variously designated as P-322, P-38F-13, P-38F-15, and P-38G-15. Several factors lost the RAF interest in the P-38.
One of the major factors that led to the RAF’s decision not to proceed with the P-38 order was the fact that the compressibility problem appeared at an altitude far lower than expected. This fact was well known to the RAF pilots making test flights; this was one of the main reasons for their decision. Other major issues, such as early problems with the Allison engines and low production rates, combined with the performance of the Mosquito to instill reluctance in the RAF. Demand from the USAAF for reconnaissance variants of the P-38 also had a bearing on production schedules.
A memorandum by Colonel H.S. Vandenberg, dated June 13, 1942, drew attention to the operational difficulties with the P-322s that the firm had manufactured for the British but could not accept in the US due to unsatisfactory features. He recommended appropriating these aircraft from the British and using them for technical training.
It would be in the Pacific theater that the P-38 would prove its combat worth. Pilot John A. Tilley of the 457th Fighter Group remembered an encounter in which he out-turned a very agile Japanese Oscar. “Miracle of miracles, the big old P-38 turned inside the nimble little Oscar,” he exclaimed, attributing his success to the counter-rotating engines, which prevented the aircraft from snapping out of control into a spin.
Comparatively, the P-38 was not a great aircraft for high-speed dives. In clean configuration, it entered compressibility between 430 and 440 mph at 25,000 feet. Even with dive brakes, the critical Mach of a P-38 was only about .68; thus, it was not as fine a diver as the P-51 Mustang and P-47 Thunderbolt. The P-51, for instance, could reach an airspeed of .75 Mach in a dive with no power or propeller, but the P-47 could dive safely to Mach .80 with flaps out for recovery.
Though it had all those downsides, it performed well in a few other ways: it out-climbed the P-47 in many cases and was known for its heavy firepower. Moreover, the installation of 100/150 fuel and a high manifold pressure made the P-38 capable of cruising over 440 mph.
Ultimately, the legacy left by the P-38 Lightning will be as much about tribulations as triumphs. Though continually plagued by operational issues and rejected by the RAF, this fighter proved its mettle in the Pacific Theater. Its unique design and capabilities ensured its place within the annals of military aviation history.