“I start the aggressive [6.5-G] pull into the vertical—and the aircraft explodes…. Any F-100 pilot who hears a loud ‘BANG!’ automatically thinks, ‘compressor stall,’” Merrill A. “Tony” McPeak F-100 Thunderbird pilot.
Developed as a follow-on to the F-86 Sabre used in the Korean War, the F-100 was the world’s first production airplane capable of flying faster than the speed of sound in level flight (760 mph). The prototype — the YF-100A — made its first flight on May 25, 1953, at Edwards Air Force Base, Calif. Of the 2,294 F-100s built before production ended in 1959, 1,274 were Ds, more than all the other series combined. The Super Sabre had its combat debut in Vietnam where it was used extensively as a fighter-bomber in ground-support missions such as attacking bridges, road junctions and troop concentrations.
The US Air Force “Thunderbird Flight Demonstration Team” operated the F-100C from 1956 until 1964, when they made the transition to the F-105. However, problems with the F-105 caused them to change back to the F-100 (D variant) before they completed the 1964 demonstration season.
As told by Ted Spitzmiller in his book Century Series The USAF Quest for air supremacy 1950-1960, one in-flight airframe failure of a Thunderbird F-100D occurred during a performance over Laughlin Air Force Base near Del Rio, Texas, on Oct. 20, 1967. The pilot was future Air Force Chief of Staff Merrill A. “Tony” McPeak, flying #6, a solo position. In his own words (from “Tony McPeak Story”):
“…We approach the climax, the signature Bomb Burst. My job is to put ‘pigtails’ through the separating formation, doing unloaded, Max-rate vertical rolls…. I start the aggressive [6.5-G] pull into the vertical—and the aircraft explodes…. Any F-100 pilot who hears a loud ‘BANG!’ automatically thinks, ‘compressor stall,’ and unloads the jet to get air traveling down the intake in the right direction. … SO INSTINCTIVELY, the explosion causes me to relax stick pressure to unload the airplane… [but—] That’s no compressor stall!!…
“In retrospect, the airplane had already unloaded itself, making my remedy superfluous, but there was some pilot lore at work here. No matter what else happens … fly the airplane. Forget all that stuff about lift and drag and thrust and gravity, just fly the damn airplane until the last piece stops moving. Good old 55-3520 has quit flying. But I have not.
“Now there’s fire, and I don’t mean just a little smoke. Flames fill the cockpit. I have to eject. I grab the seat handles and tug them up, firing the canopy and exposing ejection triggers on each side of the handles. I yank the triggers and immediately feel the seat catapult into the slipstream. …”
He lost his helmet in the high-speed bailout, but landed safely – despite a damaged parachute. He talked to Mike Miller, Thunderbirds narrator, who said “maybe we should leave ‘that thing, whatever it is,’ out of the show sequence.”
McPeak: “That’s when I learn I’d pulled the wings off the airplane.
“After I jumped out, my aircraft continued on a ballistic trajectory, scattering parts and equipment along the extended flight path. Most of the engine and the main fuselage section impacted about 2 miles downrange from my initial pull-up spot. All the bits and pieces landed on government soil, and there was no injury or property damage. My aircraft was destroyed—I signed a to hand-receipt for $696,989—but if there is a good kind of accident, this was it. Nobody was hurt, and all the scrap metal was collected for post-game analysis.
“The F-100’s wings mate into a box at the center of the fuselage, the strongest part of the airplane. When my aircraft’s wing center box was inspected, it was found to and have failed. North American Rockwell, the manufacturer, tested the box on a bend-and-stretch machine, and it broke again at an equivalent load of 6.5 G for the flight condition I was at when the wings departed.
“Later, specialists discovered considerable fatigue damage in the wing center boxes of other Thunderbird aircraft. USAF immediately put a 4 G limit on the F-100 and initiated a program to run all the aircraft through depot modification to beef up the wing center box. My accident almost certainly saved lives by revealing a serious problem in the F-100 fleet.”
The Thunderbirds performed with the D series from July 1964 until November 1968, when they upgraded to the F-4E Phantom II.
Century Series The USAF Quest for air supremacy 1950-1960 is published by Schiffer Publishing and is available to order here.
Photo credit: U.S. Air Force