8 June 1966: During a publicity photo formation flight, a Lockheed F-104N Starfighter, N813NA, flown by NASA Chief Research Test Pilot Joseph A. Walker, was caught in the wingtip vortices of the North American Aviation XB-70A-2 Valkyrie, 62-0207, the second prototype Mach 3+ strategic bomber. The Starfighter rolled up and across the Valkyrie. The two airplanes collided, with the F-104 taking off the Valkyrie’s vertical fins, then exploding.
The Valkyrie continued to fly straight and level for 16 seconds before it began to roll inverted. The B-70’s pilot, Alvin S. White, was able to eject, though he was severely injured. Joe Walker and B-70 co-pilot Major Carl S. Cross, United States Air Force, were killed.
Still photographs and motion picture film of the formation were being taken from Clay Lacy’s Gates Lear Jet. The photos were for a General Electric publicity campaign showing U.S. military aircraft that were powered by GE engines. Air Force procedures for requesting and approval of publicity flights were not properly followed and it is likely this flight would not have been approved had they been.
Reportedly, just prior to the collision, Walker radioed, “I’m opposing this mission. It is too turbulent and it has no scientific value.”
17 July 1965: At Air Force Plant 42, Palmdale, California, the second North American Aviation B-70 Valkyrie prototype, XB-70A-2-NA 62-0207, took off on its maiden flight enroute Edwards Air Force Base where it would continue the flight test program with its sister ship.
The Valkyrie was designed as a Mach 3+ strategic bomber, capable of flight above 70,000 feet (21,336 meters), with intercontinental range. It’s altitude allowed it to avoid interceptors of the time, but improvements in radar-guided surface-to-air missiles increased its vulnerability. Ultimately, though, political decisions ended the B-70 program.
62-0207 was flown just 46 times, for a total of 92 hours, 22 minutes of flight. Changes to the aircraft corrected the deficiencies discovered in testing the Number 1 XB-70A, 62,-201. The most visible change was 5° dihedral added to the wings for improved stability. On 16 April 1966, 62-0207 reached its maximum design speed, Mach 3.08, which it sustained for 20 minutes.
Less than one year after its first flight, 8 June 1966, the Valkyrie was involved in a mid-air collision with a Lockheed F-104N and crashed just north of Barstow, California. North American’s B-70 test pilot, Al White, was seriously injured and co-pilot, Major Carl Cross, USAF, was killed. NASA test pilot Joe Walker, flying the F-104, was also killed.