The outstanding U.S. land-based fighter of the World War II era was the P-51 Mustang. North American Aviation produced 14,819 Mustangs during the war, including photo (F-6) and attack (A-36) variants. The efficacy of the design led to development of the postwar F-82 Twin Mustang—essentially two P-51s “glued together”—with 272 being produced. And, in 1967, the Air Force ordered “remanufactured” Mustangs from Cavalier Aircraft Corp. for foreign transfer; these aircraft were “delivered as virtually new aircraft in the contemporary markings of the U.S. Air Force with 1967 serial numbers.”1
During the war, the U.S. Navy carefully watched aircraft development by the Army Air Forces (AAF). The only fighter that garnered interest as a naval aircraft was the Mustang, and in 1944, a P-51D was acquired for carrier evaluation. The fighter was fitted with an arresting hook attached to a reinforced bulkhead behind the tail wheel; the hook was fitted in a streamlined housing under the rudder fairing and could be released from the cockpit. In addition, the tires were replaced with special, high-pressure tires; a catapult hook was installed between the main landing gear; and the tail fin was modified. Testing began at Mustin Field near Philadelphia in September 1944.
As modified, the fighter—AAF serial 44-14017—was redesignated ETF-51D. It was not assigned a Navy bureau number, as sometimes reported. Similarly, the name “Sea Horse” has been found in some documents, but that was never an offi-cial moniker.2
Navy interest in the Mustang continued, and on 15 November 1944, Lieutenant Robert “Bob” Elder began carrier trials on board the USS Shangri-La (CV-38) off the Virginia Capes. A total of 25 landings and takeoffs were made, with the trials reported as completely successful. Landings were “easy,” with the tail wheel allowed to contact the flight deck before the main gear, and the aircraft could be stopped in minimum distance. Takeoffs were made without the use of a catapult, with a flap setting of 20 degrees down and 5 degrees of up elevator.
Landing approaches were made at 85 miles per hour, and a constant, curved approach was required, similar to that used for the F4U Corsair. Elder reported that Mustang pilot visibility over the nose was better than on the Corsair or the F6F Hellcat.
In the same period, the Shangri-La also conducted carrier trials of the North American B-25H Mitchell twin-engine bomber and the Grumman F7F Tigercat, a twin-engine fighter-attack aircraft. The B-25, of course, had gained fame when 16 of the Army bombers flew from the carrier Hornet (CV-8) to bomb Japan in April 1942. The Navy and Marine Corps were flying the B-25 with the designation PBJ-1. The F7F saw limited Navy-Marine Corps service after World War II, but was not assigned to carrier squadrons.
By the fall of 1944 the AAF had expressed interest in a carrier-based Mustang—manned by Army pilots—to escort B-29 Superfortress raids on mainland Japan. Although B-29 losses were few, especially compared to the tremendous bomber losses in the European theater, Japanese interceptors were becoming more aggressive. However, this requirement ended with the February 1945 Marine assault on the island of Iwo Jima with its several airfields, permitting the long-range Mustangs to escort the B-29s to Japan.
Although the Mustang’s carrier trials on board the Shangri-La were successful, the odds were stacked against Navy adoption of the aircraft. First, the Navy had a large number of highly capable fighters in production: the F6F Hellcat, F7F Tigercat, F8F Bearcat, and F4U Corsair, with jet-propelled fighters on the horizon. Second—and highly significant—the Mustang’s in-line engine required a liquid coolant; all Navy fighter and attack aircraft of the era had radial engines that did not need coolants. Thus, supporting the Mustang on board ship would require establishing a logistics system to procure, transport, and store the coolant on board carriers. To initiate the Navy’s operation of the Mustang simply was not worth the effort.
1. “Mustang: The Quarter-Century Fighter,” Flying Review International (April 1968), 175. Also see Gaetan Marie, “The Naval Mustangs,” at www.mustang.gaetanmarie.com/articles/naval/naval.htm.
2. The later Sikorsky HUS-1/UH-34 as flown by the U.S. Marine Corps was officially named Seahorse.
3. See N. Polmar, “The Tigercat—Too Late to Star,” Naval History (April 1998), 53; and “Mitchell in the Marines,” Naval History (December 2003), 14–15.