Lockheed P-38 Lightning P-38G

The P-38G took over from the P-38F on Lockheed's Burbank lines; the English Wikipedia dates its arrival to June 1942, while the Spanish edition places it in early 1943. Outwardly it was almost identical to its predecessor - the French Wikipedia calls it a version "quite close to the P-38F" - and the differences lay inside. The powerplant changed to the Allison V-1710-51/55 (F-10 series). Sources disagree on output: the English Wikipedia credits them with about 1,400 hp each, the German edition gives 1325 hp, and the Italian one specifies that the V-1710-55 delivered 1,150 hp, but at an altitude of 8,100 metres. The French article adds that these engines produced no more power than those of the P-38F; they were simply more durable. The other defining improvement was electronic: the official description of the variant is the production model "with modified radio equipment", and the Italian Wikipedia also mentions a new oxygen system. According to the German edition, weight was reduced compared with the P-38F, and late-production aircraft could carry bombs and rockets on underwing stations.

The P-38G also made a decisive capability standard: every Lightning from this version onward left the factory able to carry drop tanks. The Italian Wikipedia calls it "the first truly satisfactory model" of the P-38. It still carried a limitation it shared with the P-38H: the intercooler built into the wing leading edge had been designed for the YP-38's less powerful engines and restricted performance, and many crews disabled it to gain power at low level. Sources record the company designation Model 322-68 and the P-38G-5, -10, -13 and -15 blocks; the last two completed the British Lightning order. 1082 P-38Gs were built. A dozen aircraft from the programme were set aside as prototypes for what became the P-38J, with chin-mounted intercoolers, and a P-38G-10-LO was converted into the P-38K-1-LO prototype with four-bladed propellers. Some production was diverted on the assembly line to the F-5A photo-reconnaissance version, of which 181 were completed (the French Wikipedia breaks them down into 20 F-5A-1s and 140 F-5A-10s).

The episode that made the variant famous was Operation Vengeance. American codebreakers of the "Magic" programme decrypted the inspection itinerary of Admiral Isoroku Yamamoto, the architect of the Pearl Harbor attack, and the mission was given to the 339th Fighter Squadron of the 347th Fighter Group, whose drop-tank-equipped P-38Gs were the only American fighters in the Pacific with the range to intercept, engage and return. A navy compass was fitted to the aircraft of the flight leader, Major John W. Mitchell, for navigation. The aircraft took off from Guadalcanal on the morning of 18 April 1943; two of those assigned to the attack section dropped out, one with a burst tyre and the other because its drop tanks would not feed the engines, leaving 16 P-38Gs to fly the mission. They flew at wave-top height, 10 to 50 feet above the ocean and under radio silence, navigating by dead reckoning, and reached the intercept point a minute early, just as Yamamoto's two Mitsubishi G4M "Betty" bombers and their six-Zero escort were descending over Bougainville. Sources put the distance flown at between 700 and 890 kilometres. The admiral's aircraft crashed into the jungle and his body was found the next day; the second bomber, carrying Vice Admiral Matome Ugaki, came down in the sea and he survived. Lieutenant Raymond K. Hine was the only American pilot who did not return.

Credit for the kill set Captain Thomas G. Lanphier against Lieutenant Rex T. Barber for decades, and the two ended up officially sharing it. A technical trait of the variant weighed on that dispute: according to Doug Canning, who flew that day, the P-38Gs on the mission lacked the aileron boost of later models, which made it physically impossible for Lanphier to have completed the 180-degree turn he claimed in less than 30 seconds.

The P-38G served on other fronts as well. Over New Guinea, P-38G-5-LO 42-12847 "Dumbo!" of the 39th Fighter Squadron (35th Fighter Group, Fifth Air Force) flew combat missions until 2 September 1943, when, returning low on fuel and with one propeller out after escorting B-25 bombers over Wewak, it force-landed at Terapo airfield; its nose section was recovered in 1980 for the Papua New Guinea museum, and the rest of the airframe was salvaged in 2002 and taken to Australia. In the Mediterranean, on 12 June 1943 a P-38G on a special mission between Gibraltar and Malta - or perhaps just after strafing the radar station at Capo Pula - landed by mistake at Capoterra airfield in Sardinia after a compass failure; Regia Aeronautica chief test pilot Colonel Angelo Tondi flew it to Guidonia, where it was evaluated.