Yeager's NF-104 Crash
On December 10th, 1963, test pilot, Charles Elwood Yeager climbed into a modified Lockheed NF-104A equipped with a supplementary rocket engine and a reaction control system. The purpose for the test flight was to continue the testing of RCS to compensate for normal aircraft control surfaces having little or no effect in the thin air of the upper stratosphere and when operating at extremely high altitudes.
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The NF104 was powered by a General Electric J79-GE-3B turbojet, producing 9,600 lbf, along with her new reaction control systems Rocketdyne AR2-3 liquid-fuelled rocket engine, rated at 6,000 lbf. The Rocketdyne rocket engine burned a mixture of JP-4 jet fuel and 90% hydrogen peroxide oxidizer solution. For the flight, the NF-104 carried enough oxidizer for approximately 100 seconds of rocket engine operation.
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A NF-104 test profile involved a level acceleration at 35,000 feet to Mach 1.9 where the rocket engine would be ignited, and upon reaching Mach 2.1 the Starfighter would be pitched nose up to a climb angle of 50-70° by slowly applying a G load equal to 3.5. The burners would start to be throttled down at approximately 70,000 feet followed by manual fuel cutoff at 85,000 feet to prevent fast-climbing engine temperatures from damaging the turbine stages. After silently coasting over the top of its ballistic arc the Starfighter would then descend back into lower altitudes and denser air where the main engine could be restarted using the windmill restart technique for recovery to a normal landing at Edwards Air Force Base.
That day, Yeager was following the test profile that began with an acceleration to Mach 1.9. The Starfighter’s nose pitched up into her zoom climb, and she quickly passed through 37,000 feet. At that altitude, Yeager lit the NF-104A Starfighter’s rocket engine and continue the profiled acceleration to Mach 2.2 at 40,000 feet.
Passing through 70,000 feet in altitude and climbing over twice the speed of sound, Yeager was advised by ground control that his climb profile was a little shallow. To correct, Yeager applied the reaction control system to get back on climb profile. Neither the RCS, nor the flight controls would respond to Yeagers inputs…and the Starfighter, now on a ballistic path, entered a violent spin.
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As the Starfighter tumbled towards the surface, Yeager pulled the ejection handle and departed the out-of-control rocket plane as it twisted and rolled along all her axes.
The F-104 slammed onto the desert floor, with Yeager landing only a short distance away. Still in one piece, but unfortunately burned after his parachute opened. Yeager had been inadvertently struck in the face by the base of his ejection seat, breaking his helmet’s visor, and allowing burning residue from the rocket to enter the pure O2 environment inside his helmet. This sequence of events actually ignited a flame inside his visor, and as a result, Yeager suffered numerous burns to his face and hands. Moments after touching down under his canopy, a helicopter and flight surgeon arrived, and thankfully, Yeager lived to fly another day...
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Although Yeager survived, the program did not, and many blamed Yeager for asking the aircraft to do things it was never meant to do on that day. Amid accusations of improper checklists and aircraft procedures, contrary to Yeager's assertations that the NF-104 was not fit for flight, other test pilots such as Apollo Astronaut Frank Borman laid the blame for that crash squarely on Yeager's shoulders.
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And so the widowmaker was born…
Altough I am a great admirer of Chuck Yeager he flourished on attention by putting other pilots in trouble, he let Neil Armstrong land on a lake with a thin hard crust resulting in their jet breakin through the crust and the undercarraige sinking in the mud, Not a team player maybe that was why he never made it to space program
Three things went awry. One, being too shallow on his climb profile, the correction significantly decreased the horizontal stabilizer’s pitch to nose high attitude, actuated by engine driven hydraulic pump. When the turbine shut down due to overheat above 70,000 Chuck lost his hydraulic pump and the stab was stuck. Two, he either did not get high enough for his peroxide puffers to be effective, the horizontal stab attitude interfered with the puffer input, or the puffers themselves had a malfunction, either way he was not able to pitch the nose of the aircraft down at the top of his arc, this prevented the engine from windmilling to restart. He could not restart the engine. Three, his drag chute was deployed to stabilize the descent and get a nose down windmilling restart, almost worked. The chute had a designed breakaway tension, it was exceeded before effective windmilling could be achieved. Once this last ditch failed, and he was at a safe altitude, Chuck ejected. If I remember correctly the flight was his second for the day. Interesting note, on the same day of this crash the X-20 Dina-soar project was cancelled.
Hey Ben, maybe you’ll get to like the Air Force. Zooming all over the sky and shouting ROGER and WILCO and everything. Maybe it won’t be so bad.
F104 as a fast aircraft
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