"Rusty Vandura - www.tinyurl.com/keepoppo" (rustyvandura)
02/22/2019 at 12:35 • Filed to: None
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"Rusty Vandura - www.tinyurl.com/keepoppo" (rustyvandura)
02/22/2019 at 12:35 • Filed to: None | 5
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One of my favorite videos on the entire Internet. Triple-7 maximum rejected takeoff at 210 MPH. I was substituting for an 8th grade science class this morning and the topic was friction, so I showed them this video.
CaptDale - is secretly British
> Rusty Vandura - www.tinyurl.com/keepoppo
02/22/2019 at 13:16 |
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That is super cool!
WilliamsSW
> Rusty Vandura - www.tinyurl.com/keepoppo
02/22/2019 at 13:25 |
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Impressive. And I think I heard him say the discs get up to 3000 degrees - at that temperature, steel is a liquid ( hence the different disc material) .
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Rusty Vandura - www.tinyurl.com/keepoppo
> CaptDale - is secretly British
02/22/2019 at 13:30 |
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I’ve watched that video a dozen times or more and I never tire of it.
ttyymmnn
> Rusty Vandura - www.tinyurl.com/keepoppo
02/22/2019 at 14:03 |
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Pun intended?
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ttyymmnn
> Rusty Vandura - www.tinyurl.com/keepoppo
02/22/2019 at 14:09 |
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Rusty Vandura - www.tinyurl.com/keepoppo
> WilliamsSW
02/22/2019 at 14:20 |
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It’s absolutely nuts. I was on an MD-80 flight about fifteen years ago that suffered compressor stalls and the pilots shut it down. On the landing, they set
full auto-brake
. Dry runway. Boy, did that thing slow rapidly. Pretty exciting and pretty inconvenient. Had to overnight in Texarkana. My daughter got an ear infection. American lost our luggage. Merry Christmas and the last time we ever tried to fly anywhere during the Christmas holidays.
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Rusty Vandura - www.tinyurl.com/keepoppo
> ttyymmnn
02/22/2019 at 14:23 |
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No, but watching it makes a nice brake in the action.
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Rusty Vandura - www.tinyurl.com/keepoppo
> ttyymmnn
02/22/2019 at 14:23 |
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Yes, I know this video. It’s as if Airbus didn’t do any prior planning at all. Pretty comical.
3point8isgreat
> Rusty Vandura - www.tinyurl.com/keepoppo
02/22/2019 at 14:51 |
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Is that 9.7 million ftlb of energy right?
I’m not used to seeing energy in terms of ftlbs, but that seems low . After converting 9.7 Million ftlb to kJ (13,151 kJ ) I’m surprised at how little that is. That’s ~1/10th of a gallon of gasoline. Or 3.65 kWh if you want to compare it to an EV battery. And all of this seems way too low.
Some simple 1/2*M*V^2 (Using the 288 tons and 210 mph the mass is 261269 kg and speed 93.8784 m/s ), I’m getting 1.15 Million k J. This seems much more appropriately ridiculous. And that’s before even thinking about how much energy the full throttle engines are adding. So maybe the 9.7 Million is supposed to be kJ?
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3point8isgreat
> 3point8isgreat
02/22/2019 at 14:54 |
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Then again maybe there’s other missing details, like that drag thing that we like to forget in physics class. If the brakes were equivalent to 13kg of steel, total, they’d reach that 3000degF with the ftlb number they gave. Although 13kg seems light for that many, steel equivalent, brake rotors of significant size.
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WilliamsSW
> Rusty Vandura - www.tinyurl.com/keepoppo
02/22/2019 at 15:23 |
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Yuck! A couple of years ago, I was on an American 737 that seemed to be in a hol d over Lake Michigan a long time. Then the pilot came on and said we had no flaps, so we would be landing at a higher speed than normal, and would be met by the fire department. Landing was still uneventful.
I’ve flown into Midway many times, and they always hit the brakes hard on those short runways.
John Norris (AngryDrifter)
> Rusty Vandura - www.tinyurl.com/keepoppo
02/22/2019 at 17:01 |
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Thanks. Tha t was fun to watch.
And I’ m somewhat past the 8th grade, by a few measures at least .
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Rusty Vandura - www.tinyurl.com/keepoppo
> 3point8isgreat
02/22/2019 at 17:05 |
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I didn’t take Physics, okay? But I work hard at understanding things, and I have a BS degree in mathematics and I do lots of hands-on things. But here’s what I think: I think that 9.7 million lb-ft is a bending moment of torque, rather than an expression of an amount of energy , which is what kilo joules would be talking about. So maybe when Captain Happy first applied his brakes, he was exerting 9.7 million lb-ft onto the twelve wheels as he slowed that behemoth down.
#mybestguess.com
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Rusty Vandura - www.tinyurl.com/keepoppo
> WilliamsSW
02/22/2019 at 17:09 |
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The braking on that MD-80 was phenomenal. Except for my daughter’s earache, I’d say the entire experience was well worth the price of the ticket.
When the engine compressor-stalled, some smoke got far enough forward in the engine to mix into the bleed air, so we got a puff of smoke through the air conditioning ducting inside the tube. I understood exactly what had happened with that, and as people were gasping, I said, “Well folks, I don’t think we’re going to Norfolk tonight.”
We deplaned through the D.B. Cooper exit in the rear of the aircraft.
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Rusty Vandura - www.tinyurl.com/keepoppo
> John Norris (AngryDrifter)
02/22/2019 at 17:11 |
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Cool! I’m glad you enjoyed it. I never get tired of it.
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WilliamsSW
> Rusty Vandura - www.tinyurl.com/keepoppo
02/22/2019 at 17:13 |
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DB Cooper exit? I didn’t think the Mad Dog had one - the early 727's are the only ones I knew that had that.
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John Norris (AngryDrifter)
> ttyymmnn
02/22/2019 at 17:15 |
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Ge eez, what a goat rope. The flight crew wasn’t getting any evacuation help and the fire crew looked incompetent . When your job is to put out the fire you need to put the water on the fire, not spray it around indiscriminately .
I li ke h ow the hopeful test lead was sticking with the program right to the end. It’s just a small fire, don’t let them put it out .
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Rusty Vandura - www.tinyurl.com/keepoppo
> WilliamsSW
02/22/2019 at 18:04 |
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Yup; they still have ‘em.
f86sabre
> Rusty Vandura - www.tinyurl.com/keepoppo
02/22/2019 at 22:01 |
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Ah, the stories that I could tell. The wheel and brake engineers for the small aviation concern that I work for report to me. We’ve seen some stuff.
This deal saw us write off about $500k in basically new carbon brakes...
https://aeronauticsonline.com/delta-air-lines-rejected-takeoff-at-shanghai/
TheRealBicycleBuck
> Rusty Vandura - www.tinyurl.com/keepoppo
02/23/2019 at 00:01 |
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The amount of testing certificated planes go through is amazing. It’s the reason I can do repeated short-field landings to full stop without the brakes giving out. The purple dots are moments of “excessive” braking according to the app which is tracking my flights.
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Rusty Vandura - www.tinyurl.com/keepoppo
> f86sabre
02/23/2019 at 02:01 |
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So there are special RTO brakes, or just a skidmarks-in-your-underwear brake lever?
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f86sabre
> Rusty Vandura - www.tinyurl.com/keepoppo
02/23/2019 at 07:15 |
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Yeah, just a setting that allows max pressure and aggressive ABS.
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Rusty Vandura - www.tinyurl.com/keepoppo
> f86sabre
02/23/2019 at 07:55 |
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Essenti ally full auto-brake?
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f86sabre
> Rusty Vandura - www.tinyurl.com/keepoppo
02/23/2019 at 09:26 |
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Yep.
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Rusty Vandura - www.tinyurl.com/keepoppo
> f86sabre
02/23/2019 at 13:15 |
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Did you see my
full auto-brake story
above?
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f86sabre
> Rusty Vandura - www.tinyurl.com/keepoppo
02/23/2019 at 14:36 |
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Yeah. Airliners are pretty capable. People don’t realize it most of the time because the pilots are trying to keep things smooth.
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Rusty Vandura - www.tinyurl.com/keepoppo
> f86sabre
02/23/2019 at 15:36 |
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For as much of a hassle as that was, it was pretty exciting. The pilot was great. When we were all sitting around the terminal eating Domino's Pizza after we landed, I got to talk pilot stuff with the pilot and he was eager to chat about the event. Pilots are funny. They don't really enjoy inane questions from inane passengers but once you get past the point where they figure out that you really do have a clue and you're asking informed questions, then they generally enjoy talking about their craft.
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Rusty Vandura - www.tinyurl.com/keepoppo
> f86sabre
02/23/2019 at 15:37 |
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I hada flight where the way that aircraft was handled had a certain crispness to it that stood out and when I chatted up the pilot, it was a woman who’d been flying for 40 years, and had begun her career as a C-130 pilot in the Marine corps. Certified badass, in my book.
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f86sabre
> Rusty Vandura - www.tinyurl.com/keepoppo
02/23/2019 at 16:15 |
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Yeah, you can tell when the flight controls have a snap to them.