Watch pilots eject at over Mach 8 on test track

Originally published at: https://boingboing.net/2018/07/30/watch-pilots-eject-at-over-mac.html

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Damn that is fast… also I think those are not real people in the test.

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“Pilots” = mannequins
“Mach 8” = subsonic

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Yeah, I should have been clearer that the first ones are dummies, but there is some footage of humans strapped onto that rocket sled.

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Mach 8 is over 6000 MPH. Sorry, but that aint right.

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They discuss it later on, but I was kind of worried before then. Asking humans to be brave for a safety test is one thing, but suicidal is another.

I hope there’s a lot of technology and knowledge transfer going on between this facility and the civilian aviation and automobile industries. Few of us are ever going to reach the test track speeds but I’d imagine there are a lot of safety innovations learned there that are applicable to keeping us all safe.

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Highway to hell.

My fighter pilot dad took me to the firing range there once. Not much to see on the ground in the way of targets but, what I remember are the shipping crate size dumpsters heaping with spent shells from F4 Phantom jets collected from the grounds.

In all the time in combat my father never had to eject but, he had friends who did and survived because of such efforts. I bet it was one a hell of a ride.

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Mach, the speed of sound, is a function of air density and humidity, and as such changes with altitude.

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Cool, but needs more Kerbals.

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There more than likely is a ton. I know that a bunch of the lifesaving technology for infants all came from Air Force medical research to treat injured pilots.

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We don’t want a rapid unplanned disassembly now do we?

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While the test track can indeed propel payloads (non-living) to Mach 8 and a bit beyond, let’s be clear that NO human has ever intentionally ejected from anything going much more than Mach 1. Only a handful of people have had to do it and survived. But you would never intentionally eject a human at supersonic speeds unless testing some radical capsule ejection system of the sort that might have been used (but wasn’t) on the STS (Space Shuttle). In an ejector seat? Never. (Nor could this sled accelerate a payload that large to Mach 8 anyway.)

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Wikipedia: “Col. Stapp was the last human test subject to ride the rocket-powered sleds at the HHSTT in December 1954.”

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Doesn’t look like the eject tests were at that speed but the track has accelerated sleds that much as they hold the land speed record for a railed vehicle.

Unmanned. 6,416 mph (10,326 km/h) = Mach 8.4. Final stage of a four-stage sled train. Super Roadrunner rocket motor. 192 lb (87 kg) payload. For more than 2 miles (3 km) the sled was in a helium tube to reduce air friction.

From some other comments it sounds like the sled may have melted a bit when it came out of the helium tube at Mach 8.4.

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I think the problem is that while the test track can accelerate things to over Mach 8, that’s for testing scramjet warheads, rail-gun rounds, and the like, not ejection seats.

Since no piloted US military jets go faster than about Mach 2.5 (or Mach 3.2 if we include the retired SR-71), there’s no point in testing an ejection seats at super-high velocities. So I’m pretty confident that we are not seeing “pilots ejecting” (or dummies ejecting) at “over Mach 8”.

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On Dec. 10, 1954, Lt. Col. John Stapp became the “Fastest Man on Earth” when he rode a rocket-propelled sled at a speed of 632 miles per hour, in the process enduring more than 40 times the pull of the Earth’s gravity and suffering various injuries, including broken ribs and a temporarily detached retina. His sled run provided pivotal information on how gravitational stress affects the human body. (from Holloman AFB site)

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Interesting to note he was in his 40s at the time, too. They say in the piece he experienced 40 Gs of deceleration.

On his final run in a rocket sled, Stapp reached a peak velocity of 632 mph (20G) while being hit by two tons of wind pressure. He then hit the brakes and came to a stop in 1.4 s experiencing a record setting 46.2G. Stapp had suffered a complete red out and was just barely conscious. The jolt burst nearly every capillary in his eyeballs, he was blinded, but his retinas did not detach. He slowly regained his bearings and within a day his vision was back to normal.

https://www.quora.com/How-much-instantaneous-acceleration-deceleration-can-a-human-body-sustain-without-significant-internal-damage-For-example-at-what-accelerations-would-a-futuristic-spacecraft-be-limited-to-if-it-had-humans-on-board

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Regardless the speeds the sled is going, I’m looking at that ejection and feeling the inevitable crunch on every vertabra from head to tail bone. Brrrr.

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Seems a bit unfair to refer to them as that.

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Wheeeee…

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