Test pilot Charles F. “Chuck” Fisher was able to land the damaged B-52 with only about 15% of its fin remaining
On Jan. 10, 1964, a Boeing B-52H Stratofortress instrumented by Boeing-Wichita was being used to test buffeting turbulence effects on aircraft.
The crew, headed by test pilot Charles F. “Chuck” Fisher, was performing an eight-hour flight that would test indicated airspeeds of 280, 350, and 400 knots over mountainous terrain at 500 feet altitude above the ground.
During the mission, the turbulence became very strong the crew discontinued the mission and climbed to 14,000 feet. Then the aircraft was moved sharply to the right and sideways through the air by a sudden five-second blast of clear air turbulence which ripped off the vertical fin. As told by Walter J. Boyne in his book Boeing B-52 A Documentary History, Fisher stated that it felt like a severe edged blow, followed by several more. Instantaneously the aircraft rolled to the left at a high rate, the nose swinging up and to the right rapidly. Fisher reduced power to idle and the B-52 rotated nose down.
He then applied full opposite controls without any effect since the rudder pedals were locked. Fisher was able to reduce the airspeed down to 210 knots by applying airbrakes. With 80 degrees of wheel deflection, he was able to stabilize the aircraft in somewhat level flight.
The three hours that followed involved some very sensitive flight: in fact even if the crew knew how important it was to get the instrumented aircraft back safely (so that the data of an incident which had caused other crashes would be preserved), they had no idea if the damage would propagate, throwing the aircraft out of control.
Long-time test pilot Dale Felix took off in a North American F-100 to act as chase aircraft. Felix joined up with the B-52 and while he was surveying the damage he heard Fisher remarking “we’ve slowed down to 220 knots, we’re stable, and I’m going to handle it pretty carefully.” Felix cut in with “Chuck, that’s a good idea,” and added, “All of your rudder and most of your vertical fin are gone.”
As reported by Boyne, there was a silence and Fisher said “Don’t I even have 50%?” Felix replied, “No, you don’t have 50%.” Actually, there was only about 15% of the fin remaining.
The aft main gear was lowered to gain some lateral directional stability.
The crew was ready to eject but Fisher along with the co-pilot Dick Curry decided they could try to land the aircraft. The aircraft was carefully flown to Blytheville Air Force Base (AFB), Arkansas, where the wind was straight down the runway and an approach could be made over an unpopulated area. Fisher brought the aircraft in, flaps up. He recalls “the landing was not my best one but the airplane was drifting left off the runway and the only way to stop it was to get it on the ground.”
The data collected by the instrumented B-52 showed that even if some improvements in structure could be made, no aircraft could be made safe from the most extreme values of clear air turbulence. The best way to avoid such accidents was to plan flights to stay away from them.
The following video film is an Aerospace Flight Safety report released by the U.S. Air Force (USAF) which details the events that occurred, with supporting footage from chase aircraft and ground cameras.
Photo by U.S. Air Force
