The Northrop F-15 Reporter (later RF-61) was an American unarmed photographic reconnaissance aircraft. Based on the Northrop P-61 Black Widow night fighter, it was the last piston-powered photo-reconnaissance aircraft designed and produced for the United States Air Force. Though produced in limited quantities, and with a relatively short service life, the F-15's aerial photographs of the Korean Peninsula would prove vital in 1950, when North Korea invaded the south. The F-15 Reporter was created when the guns were removed from the experimental XP-61E, the last fighter variant of the P-61 Black Widow. With less than six months flying time, the first XP-61E was taken back to the Northrop modification shop where it was converted into an unarmed photographic reconnaissance aircraft. All the guns were removed, and a new nose was fitted, capable of holding an assortment of aerial cameras. The aircraft, redesignated XF-15, flew for the first time on 3 July 1945, with Northrop test pilot L. A. "Slim" Parrett at the controls. A P-61C-1-NO (serial number 42-8335) was also modified to XF-15 standards as the XF-15A. Apart from the turbosupercharged R-2800-C engines, it was identical to the XF-15 and flew for the first time on 17 October 1945. For unknown reasons Northrop subcontracted the nose for the F-15A to the Hughes Tool Company of Culver City, California. The F-15A used the existing P-61C wings (without fighter brakes), engines and tail sections but with an entirely new, more streamlined fuselage housing a crew of two under a continuous bubble-canopy. As a result of continuing development trouble with the Howard Hughes-designed XF-11, the staff of the Army Air Force Headquarters determined an immediate need for 320 F-15 Reporters. Even before the first flight of the XF-15 an initial contract for 175 aircraft was signed in June 1945. Following testing it was determined that the F-15 Reporter possessed similar performance and flight characteristics to the troublesome XF-11, despite the Reporter being powered by less powerful engines, and using mostly pre-existing parts. This spelled the end to further development of the XF-11. The first production F-15A was accepted in September 1946. However, the contract was abruptly canceled in 1947, possibly because the performance of the aircraft was rapidly being overshadowed by jets, with the last of only 36 examples being accepted by the United States Army Air Forces in April of that year. The last F-15 to be produced (serial number 45-59335) was produced as an F-15A-5-NO, which differed from the Block-1 version mainly in having a new internal camera installation in the nose. It seems that this change had been contemplated for the last 20 F-15s as well, since some records indicate that these were all eventually re-designated as F-15A-5-NO. The F-15 had a revised center pod with pilot and camera operator seated in tandem under a single bubble canopy. The first XP-61E, from which the first XF-15 was converted, had the canopy hinged to the side, while all subsequent XF-15 and production F-15 employed a sliding canopy. The aircraft's six cameras were placed in an elongated nose, replacing the XP-61Es four guns. Production F-15A were powered by the same turbosupercharged R-2800-73 engines as the P-61C. The aircraft had a takeoff weight of 32,145 lb (14,580 kg) and a top speed of 440 mph (382 kn, 708 km/h) at 33,000 ft (10,058 m). In the end, only 36 of the 175 ordered F-15As were built, and all were constructed from aircraft originally contracted to be built as P-61C. Variants XF-15 The first prototype, converted from the first XP-61E. XF-15A The second prototype, converted from a P-61C (number 43-8335). F-15A Reporter Photoreconnaissance variant with a new center pod with pilot and camera operator seated in tandem under a single bubble canopy, and six cameras taking place of radar in the nose. Powered by the same turbosupercharged R-2800-73 engines as the P-61C. The aircraft had a takeoff weight of 32,145 lb (14,580 kg) and a top speed of 440 mph (382 kn, 708 km/h). Only 36 of the 175 ordered F-15As were built before the end of the war. After formation of the United States Air Force in 1947, F-15A was redesignated RF-61C. F-15As were responsible for most of the aerial maps of North Korea used at the start of the Korean War. RF-61C Reporter (Specifications below) USAF designation for the F-15C from 1948 onwards. Number built 36