"WilliamsSW" (williamssw)
03/24/2019 at 11:10 • Filed to: Planelopnik, Ameristar 9363
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"WilliamsSW" (williamssw)
03/24/2019 at 11:10 • Filed to: Planelopnik, Ameristar 9363 | 5
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This got lost in the news a bit, for a bunch of reasons. Perhaps the biggest reason was that not one of the 116 people aboard the flight was seriously injured, although the accident did occur two years ago, as well. AvWeb has a great article on it, which I highly recommend.
!!!error: Indecipherable SUB-paragraph formatting!!!
Mark Radloff and Andreas Gruseus were flying by the book - until they quickly realized that the book was wrong for their situation. They aborted the takeoff past V 1 - the speed at which the book says you continue the takeoff no matter what, because if you abort at that point, you *will* go off the end of the runway. Why did they do it? Because “it wasn’t flying”. And it would not have flown. Take a close look at the elevators (2 - left and right) in the photo of the aircraft:
The right elevator (yes, they’re separate) was jammed in the full nose down position. I recommend reading the article by Rick Durden linked above, but the bottom line was that there wasn’t a way for the pilots to know that.
While it may be easy to think that ‘well the plane wasn’t flying so of course they aborted’, the quick reaction of the crew made all the difference. When the pilot flying called ‘Abort’, the aircraft was traveling at about 187 mph across the ground- and was accelerating. Just 1 more second, and they would be 275 feet down the runway, at a higher speed. Maybe they hit the elevated road at 80 or 100 knots instead of 40 knots. And then we would be talking about the University of Michigan basketball tragedy right now during March Madness - that’s who was on board the flight.
All because a flight crew called upon their years of training by the book, and knew in an instant that the book was only *almost* always right.
If you really want to geek out, here’s the full report:
!!!error: Indecipherable SUB-paragraph formatting!!!
facw
> WilliamsSW
03/24/2019 at 11:25 |
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Here in Kinjaland, Deadspin ran a story on this (obviously light on the details):
!!! UNKNOWN CONTENT TYPE !!!
You can jump to ttyymmnn’s comments here: https://deadspin.com/1833150532
ttyymmnn
> WilliamsSW
03/24/2019 at 11:42 |
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That was a good read. There was a piece over on Deadspi n about this the other day, and I spent a bit of time reading the NTSB report. I was sitting backstage last night working on my TDIAH posts when the timpani player asked me my opinion on the MAX. I said, “I think it’s a safe aircraft. In the hands of a trained pilot.” Obviously, training makes all the difference, and these guys knew their business. And even though he was senior, the check airman knew when to follow orders from the pilot flying.
FTA:
The airplane was full, and the takeoff speeds were correspondingly high. V 1 , the “you’re going to take this airplane into the air come hell or high water because there’s no longer enough runway to stop speed” was 139 knots. V R , rotation speed—where the pilot starts pulling back on the yoke to raise the nose—was 142 knots. V 2 , the takeoff safety speed—that must be attained by an altitude of 35 feet—was 150 knots.
I’m assuming that these are the numbers for that specific day, and that those numbers will change under weather and load conditions? My son and I were at the airport one day and he asked me how fast the plane is going with it takes off. I had a friend who flew the Mad Dog for ValueJet back in the day, so I called and asked him. He said, “Uh, well, it depends.” So how do they figure these speeds preflight? Lots of math, but are there charts etc that they would have used?
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facw
> ttyymmnn
03/24/2019 at 11:54 |
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There definitely are charts, though at this point, they might be replaced by other calculators? The good news is that your air speed indicator displays speed through the air, so steady winds are sort of built into the indicated takeoff speed (though needed runway length is a different story) .
For fun (but not exactly related, they are all zero wind), take a look at the charts here:
https://www.boeing.com/commercial/airports/plan_manuals.page
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WilliamsSW
> ttyymmnn
03/24/2019 at 11:57 |
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I saw the Deadspin article, and it was a bit sensationalist, but not bad. A lot of crap in the comments section though, and there hasn’t been a lot of coverage on it. I really wanted to highlight the Avweb article and discuss that here.
Those speeds are dependent on a whole host of factors - including winds, temperature, barometric pressure, aircraft weight, and runway length. V1 is basically the speed you can accelerate to, then abort, and stop at the end of the runway. Past that, there’s a near certainty that you’re going to overrun - which leads to bad things in most cases.
Urambo Tauro
> facw
03/24/2019 at 11:57 |
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Deadspin? No wonder I missed the article when it originally ran.
Yeah, I can see why it has a place on that blog, but I would argue that the news i s primarily transportation -related and should have been published on Jalopnik first. ... And then yes of course share it to Deadspin.
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WilliamsSW
> ttyymmnn
03/24/2019 at 11:58 |
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Oh and to answer your question, they’re using computers to calculate that. Charts in the old days before every pilot had an iPad.
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WilliamsSW
> Urambo Tauro
03/24/2019 at 11:59 |
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Yes,
and
that’s
why
I
brought
it
here.
And
the
Avweb
article >>
the
Deadspin
article.
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facw
> Urambo Tauro
03/24/2019 at 12:06 |
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I think it did get crossposted to Jalopnik. But yeah, the other way around would make more sense.
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WilliamsSW
> facw
03/24/2019 at 12:09 |
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They use iPads or whatever now, which is nice because there are a lot of factors that go into those speeds. But they did use those paper charts for a long time .
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Urambo Tauro
> facw
03/24/2019 at 12:13 |
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Huh. If it did get shared, then maybe I skimmed right past it. Maybe it had a smaller thumbnail like the Kinja Deals stuff.
wafflesnfalafel
> WilliamsSW
03/24/2019 at 12:59 |
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love it - an entire career’s worth of skill, experience and intuition compressed into FIVE SECONDS of decision making.
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WilliamsSW
> wafflesnfalafel
03/24/2019 at 13:16 |
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Exactly. And they nailed it.
As Dur den noted in the article, it’s not every day that the NTSB calls out the crew as contributing to the survivability of the accident.
The NTSB’ s job is to nit pick and look for improvement opportunities. It often comes across as harsh, but it’s a key part of what makes our air travel system so safe.
MiniGTI - now with XJ6
> WilliamsSW
03/24/2019 at 18:55 |
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Yeesh— darn good thing they didn’t get off the ground!
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WilliamsSW
> MiniGTI - now with XJ6
03/24/2019 at 19:03 |
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Well, the airplane wasn’t capable of getting airborne, but if they had just waited a few more seconds to abort, they might have hit the em bankment at 120 mph instead of 45. Huge difference in the result if that happens.