YF-104A 52955 (55-2955) first flight at Edwards AFB on February 17, 1956 YF-104A, construction number 1001, US serial number 55-2955, built by Lockheed first flight December 31, 1955, public roll-out on February 16, 1956, delivery date February 17, 1956 made its first flight at Edwards AFB on February 17, 1956 with Lockheed test pilot Herman "Fish" Salmon at the controls reached Mach 2 on February 28, 1956, becoming the first fighter aircraft capable of double-sonic speed in level flight 83 FIS Hamilton AFB, California, written off April 25, 1957 after a crash upon a too hard landing at Edwards AFB on runway 25 the nose was broken off though behind the cockpit, right main gear collapsed and the plane skidded, left gear collapsed, no fire pilot Jack "Suitcase" Simpson, a civilian engineering test pilot, abandoned the aircraft with no injuries. The aircraft got the nickname "Apple Knocker" around January 1957 The seventeen YF-104A service test aircraft (serials 55-2955/2971) were powered by early experimental versions of the General Electric J79 engine instead of the J65 engine which powered the XF-104s. The YF-104A aircraft were initially fitted with the General Electric XJ79-JE-3 turbojet, rated at 9300 lb.s.t. dry and 14,800 lb.s.t. with afterburner The YF-104A differed from the XF-104 in having a 5 feet 6 inch extension in the length of the fuselage to accommodate the new J79 engine. The vertical fin was slightly taller, raising the overall height from 12.7 feet to 13.49 feet. copyright © Airbus archive