North American XB-70 Valkyrie
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Incidents and accidents
Incidents
On 7 May 1965, a 3-foot (91 cm) piece of the apex of the wing broke off in flight and caused extensive damage to five of the six engines. They were sent to GE and repaired. The sixth engine was inspected and re-installed in the aircraft.
On 14 October 1965, AV-1 surpassed Mach 3, but heat and stress damaged the honeycomb panels, leaving 2 ft (61 cm) of the leading edge of the left wing missing. The first aircraft was limited to Mach 2.5 afterwards.
Mid-air collision
The aircraft formation before the collision on 8 June 1966; the F-104, with a red tail, is the second plane from the right.
The aircraft formation immediately after the collision; the F-104 has exploded, while the XB-70 is missing one of its vertical stabilizers. The F-4, F-5 and T-38 had yet to break formation.
On 8 June 1966, XB-70A No. 2 was in close formation with four other aircraft (an F-4 Phantom, an F-5, a T-38 Talon, and an F-104 Starfighter) for a photoshoot at the behest of General Electric, manufacturer of the engines of all five aircraft. After the photoshoot, the F-104 drifted into the XB-70's right wingtip, flipped and rolled inverted over the top of the Valkyrie, before striking the bomber's vertical stabilizers and left wing. The F-104 then exploded, destroying the Valkyrie's vertical stabilizers and damaging its left wing. Despite the loss of both vertical stabilizers and damage to the wings, the Valkyrie flew straight for 16 seconds before it entered an uncontrollable spin and crashed north of Barstow, California. NASA Chief Test Pilot
Joe Walker (F-104 pilot) and Carl Cross (XB-70 co-pilot) were killed.
Al White (XB-70 pilot) ejected, sustaining serious injuries, including the crushing of his arm by the closing clamshell-like escape crew capsule moments prior to ejection.
The USAF summary report of the accident investigation stated that, given the position of the F-104 relative to the XB-70, Walker, the F-104 pilot, would not have been able to see the XB-70's wing, except by uncomfortably looking back over his left shoulder. The report said that it was likely that Walker maintained his position by looking at the fuselage of the XB-70, forward of his position. The F-104 was estimated to be 70 ft (21 m) to the side of the fuselage of the XB-70 and 10 ft (3.0 m) below. The report concluded that from that position, without appropriate sight cues, Walker was unable to properly perceive his motion relative to the Valkyrie, leading to his aircraft drifting into the XB-70's wing. The accident investigation also pointed to the wake vortex from the XB-70's right wingtip as the reason for the F-104's sudden roll over and into the bomber.
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