Aviation: Coming In on A Wing & A Pliers

The XB-70 Valkyrie is the world's most sophisticated manned aircraft —and one of the fastest and heaviest.

Sometimes known as "Cecil the Seasick Sea Serpent" because of early technical problems and its droopy, attenuated profile, the 2,000-plus-m.p.h., 225-ton plane was originally intended to be an intercontinental bomber but was later rejected for that role. Instead, only two were built, and they have served as an invaluable flying test bed for the myriad technical problems involved in developing a supersonic transport. The second and better-equipped of the two Valkyries also tested to the utmost the nerve and ingenuity of its pilots on a recent routine flight.

Outwitting the Computer. The first hint of trouble came five seconds after the $500 million plane lifted off from Southern California's Edwards Air Force Base. Hearing a loud thump on the fuselage and seeing a red warning light blinking on the control panel, Alvin White, 47, North American Aviation's chief test pilot in the West, and his copilot, Air Force Colonel Joseph Cotton, 44, knew something was amiss with their landing gear. Pursuit jets monitoring the flight reported that one of the two tires on Cecil's forward gear had blown and the entire assembly was jammed against the partly open doors of the wheel cavity. A computer governing the gear's operation had malfunctioned, causing the doors to start closing before the gear had fully retracted. One door had knifed into a tire, and the entire mechanism was locked in an inoperative position. Inability to free it would leave the pilots no choice but to abandon their aircraft over the desert, since the plane is too heavy and comes in too fast (300 m.p.h.) for an emergency belly landing.

While White and Cotton tried desperately to move the gear by whipping the plane's nose up and down, ground engineers pored over charts in order to pinpoint the exact cause of the trouble. They concluded that a short circuit had snarled the computer, which was programmed to allow the landing gear to rise and descend only when the wheel-cavity doors were fully open. Control of the gear thus had to be removed from the computer. By causing a second short circuit, ground engineers advised, the pilots might manage to circumvent the computer and disengage the landing gear from the cockpit.

Sweating Hands. The first problem for Cotton was to find the one minute area for manipulation among thousands of miles of wire and innumerable relay points. For 75 minutes, while White piloted the plane, Cotton crawled back and forth between Cecil's innards and the cockpit, where he could get guidance from the ground. He was armed with the flashlight, screw driver and pliers that he always carries with him when flying. Finally he thought he had located the right relay switch. Taking a dime-store binder clip that he uses to hold papers in his documents case, Cotton ripped off one of the clasp's wire handles, stripped an equipment strap for insulation ("My hands were sweating") and inserted the wire with the pliers. "Okay, okay!" he yelled to White, who then pushed the forward-gear button. A pursuit plane radioed that the gear was descending as intended and seemed to be locking into place.