pilots it was Yamamoto, to "provide additional incentive" to the fliers. The specially fitted P-38s took off from Kukum Field on Guadalcanal beginning at 07:25 on April 18. Two of the Lightnings assigned to the killer flight dropped out of the mission at the start, one with a tire flattened during takeoff (McLanahan) and the second when its drop tanks would not feed fuel to the engines (Moore). In Rabaul, despite urgings by local Japanese commanders to cancel the trip for fear of ambush, Yamamoto's airplanes took off as scheduled for the trip of . They climbed to , with their fighter escort at their 4 o'clock position and higher, split into two V-formations of three planes. Mitchell's flight of four led the squadron at low altitude, with the killer flight, now consisting of Lanphier, Barber, and spares Besby F. Holmes and Raymond K. Hine, immediately behind. Mitchell, fighting off drowsiness, navigated by flight plan and the navy compass. This has been called the longest-distance fighter-intercept mission of the war. Mitchell and his force arrived at the intercept point one minute early, at 09:34, just as Yamamoto's aircraft descended into view in a light haze. The P-38s jettisoned the auxiliary tanks, turned to the right to parallel the bombers, and began a full power climb to intercept them. The tanks on Holmes's P-38 did not detach and his two-man element turned back toward the sea. Mitchell radioed Lanphier and Barber to engage, and they climbed toward the eight aircraft. The nearest escort fighters dropped their own tanks and dived toward the pair of P-38s. Lanphier immediately turned head-on and climbed towards the escorts while Barber chased the diving bomber transports. Barber banked steeply to turn in behind the bombers and momentarily lost sight of them, but when he regained contact, he was immediately behind one and began firing into its right engine, rear fuselage, and empennage. When Barber hit its left engine, the bomber began to trail heavy black smoke. The Betty rolled violently to the left and Barber narrowly avoided a mid-air collision. Looking back, he saw a column of black smoke and assumed the Betty had crashed into the jungle. Barber headed towards the coast at treetop level, searching for the second bomber, not knowing which one carried the targeted high-ranking officer. Barber spotted the second bomber, carrying Chief of Staff Vice Admiral Matome Ugaki and part of