Editing Lockheed P-38 Lightning (section)

===Range extension===
The strategic-bombing proponents within the USAAF, nicknamed the [[Bomber Mafia]] by their ideological opponents, had established in the early 1930s a policy against research to create long-range fighters, which they thought would not be practical; this kind of research was not to compete for bomber resources. Aircraft manufacturers understood that they would not be rewarded if they installed subsystems on their fighters to enable them to carry [[drop tank]]s to provide more fuel for extended range. Lieutenant Kelsey, acting against this policy, risked his career in late 1941 when he convinced Lockheed to incorporate such subsystems in the P-38E model, without putting his request in writing.   Kelsey possibly was responding to Colonel [[George William Goddard]]'s observation that the US sorely needed a high-speed, long-range [[photo reconnaissance]] plane. Along with a [[change order]] specifying some P-38Es be produced with guns replaced by photoreconnaissance cameras, to be designated the F-4-1-LO, Lockheed began working out the problems of drop-tank design and incorporation. After the attack on Pearl Harbor, eventually about 100 P-38Es were sent to a modification center near [[Dallas, Texas]], or to the new Lockheed assembly plant B-6 (today the [[Burbank Airport]]), to be fitted with four K-17 [[aerial photography]] cameras. All of these aircraft were also modified to be able to carry drop tanks. P-38Fs were modified, as well. Every Lightning from the P-38G onward was capable of being fitted with drop tanks straight off the assembly line.{{sfn|Bodie|2001|pp=89–91}}

In March 1942, General Arnold made an off-hand comment that the US could avoid the [[Battle of the Atlantic|German U-boat menace]] by flying fighters to the UK rather than packing them onto ships. [[Franklin D. Roosevelt|President Roosevelt]] pressed the point, emphasizing his interest in the solution. Arnold was likely aware of the flying radius extension work being done on the P-38, which by this time had seen success with small drop tanks in the range of {{convert|150|to|165|gal|L|abbr=on}}, the difference in capacity being the result of subcontractor production variation. Arnold ordered further tests with larger drop tanks in the range of {{convert|300|to|310|gal|L|abbr=on}}; the results were reported by Kelsey as providing the P-38 with a {{convert|2500|mi|km|adj=on}} ferrying range.{{sfn|Bodie|2001|pp=89–91}} Because of available supply, the smaller drop tanks were used to fly Lightnings to the UK, the plan called [[Operation Bolero]].

Led by two [[Boeing B-17 Flying Fortress]]es, the first seven P-38s, each carrying two small drop tanks, left [[Presque Isle International Airport|Presque Isle Army Air Field]] in Maine on 23 June 1942 for [[RAF Heathfield]] in Scotland. Their first refueling stop was made in far northeast Canada at [[CFB Goose Bay|Goose Bay]]. The second stop was a rough airstrip in Greenland called [[Narsarsuaq Air Base|Bluie West One]], and the third refueling stop was in [[Iceland]] at [[Naval Air Station Keflavik|Keflavik]]. Other P-38s followed this route, with some lost in mishaps, usually due to poor weather, low visibility, radio difficulties, and navigational errors. Nearly 200 of the P-38Fs (and a few modified Es) were successfully flown across the Atlantic in July–August 1942, making the P-38 the first USAAF fighter to reach Britain and the first fighter ever to be delivered across the Atlantic under its own power.{{sfn|McFarland|Newton|2006|p=103}} Kelsey himself piloted one of the Lightnings, landing in Scotland on 25 July.{{sfn|Bodie|2001|pp=101–102}}