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United B772 at Denver on Feb 20th 2021, engine inlet separates from engine

avherald.com

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Re: United B772 at Denver on Feb 20th 2021, engine inlet separates from engine

#101
post #9
post #3

How's that possible it managed to fly with only one engine ?

It’s designed to fly with only one engine. Not with great performance, but it will stay in the air. Routine procedure for twin engine aircraft.

Not only fly but climb.

Commercial aircraft are required to fly safely should one of the two engines fail at any point of the flight, including takeoff at speeds beyond v1.

Re: United B772 at Denver on Feb 20th 2021, engine inlet separates from engine

#102

You can hear the air/ground communications for this flight here via LiveATC.net. The pilots declare an emergency and then a mayday call beginning at 1:15 of the audio. https://forums.liveatc.net/index.php?action=dlattach;topic=1...

Curious, I had always heard it should be repeated 3 times, but here they’re consistently repeating just twice.

Re: United B772 at Denver on Feb 20th 2021, engine inlet separates from engine

#103
post #88

You can hear the air/ground communications for this flight here via LiveATC.net. The pilots declare an emergency and then a mayday call beginning at 1:15 of the audio. https://forums.liveatc.net/index.php?action=dlattach;topic=1...

You can hear the fire alert going off before the mayday. The fact that they requested a left turn at first it meant the controller knew the right engine was out and they'd need left turns to come in. Always find the level of training impressive and I'm glad they made it back safely. Aviate, Navigate, Communicate

Can't wait for the synopsis on the Blancoliro YT channel.

Re: United B772 at Denver on Feb 20th 2021, engine inlet separates from engine

#104
post #41
post #39

Earlier quoted context omitted.

Yes, hence why I said the press will focus on this because of parts raining down. An airliner having an engine issue and returning single engine though is a routine thing... usually without missing parts.

Uncontained engine failures are cause to ground whole fleets of planes, even if the resulting emergency ended up mild. You're downplaying it way too much.

Also a similar event has happened before on a United Boeing 777-200 en route to Hawaii from Denver in 2016.

http://avherald.com/h?article=4999bec5

Also another similar event on a United Boeing 777-200 en route to Hawaii in 2018.

http://avherald.com/h?article=4b4e8ca7

Re: United B772 at Denver on Feb 20th 2021, engine inlet separates from engine

#105
post #8

Earlier quoted context omitted.

Planes must be able to do this to be certified.

Well, assuming they have two+. A C-172 isn’t gonna fly too far with an engine out.

But, the pilot should be assuming that its single engine will fail, and prepared for that eventuality when it's most likely, which is during take off.

Every flight the person sat at the controls ought to already know, before they're accelerating down the runway, what they're going to do when (not if, if you keep flying these little prop planes you've got to assume it'll happen eventually) the engine quits. What's beyond that airfield fence? A carpark? A pond? A school?

The "impossible turn" (landing where you took off) might legitimately be a valid strategy for your failure in some circumstances if you've thought it through, but if you're doing it because you had no plan you're very likely to find out why they call it that.

Re: United B772 at Denver on Feb 20th 2021, engine inlet separates from engine

#106

Earlier quoted context omitted.

What, you don’t like the anchor people on TV asking each other how they feel about every piece of news and making horrible puns at every opportunity? Or having expected announcements be reported as BREAKING NEWS?

As a European who tuned in to US News for the US election I thought that was crazy. I'd watch a few of the right media orgs to see what they were saying and then stay on CNN/MSNBC etc for most of it. It's mad how so much of it every hour was essentially people just regurgitating stuff to fill the time. I mean OK what's happening is important but if you can't fill the airtime why not shift to other news (as in everyth…

Fear makes things memorable, makes it hard to turn away. It's an evolutionary thing.

If my mom calls me after she has been watching that shit, she sounds strung out on stimulants. Agitated, easily angered. She is normally a calm, fairly rational person.

It's fear mongering and it exists because it is effective. If one gets caught up in it, it can be hard to take a step back and realize what is going on. One might hear rationalizations like "I have to stay informed" or "it is related to my work". Very similar behaviour to other addictions.

I'm reminded of Tool lyrics:

"Stare like a junkie Into the TV Stare like a zombie While the mother Holds her child Watches him die Hands to the sky crying Why, oh why? 'cause I need to watch things die From a distance Vicariously I, live while the whole world dies You all need it too, don't lie

Why can't we just admit it?"

Re: United B772 at Denver on Feb 20th 2021, engine inlet separates from engine

#107

Earlier quoted context omitted.

How do you account for oceans?

By having airports on islands, or by pushing up the number of minutes that the engines/operator are certified for.

Note that ETOPS goes beyond just engine ratings, it also requires the operator meet all sorts of additional requirements (what if you DO have to divert - can you have the passengers retrieved within 24 hours, do you have food and shelter if you have to divert to a non-commercial airport along the flight path, are your technicians doing proper maintenance, etc).

Re: United B772 at Denver on Feb 20th 2021, engine inlet separates from engine

#108
post #88

Earlier quoted context omitted.

You can hear the fire alert going off before the mayday. The fact that they requested a left turn at first it meant the controller knew the right engine was out and they'd need left turns to come in. Always find the level of training impressive and I'm glad they made it back safely. Aviate, Navigate, Communicate

I don't follow how the right engine being out means left turns. Seems like you'd have extra thrust on the left side and you'd want to make right turns. They wanted to keep the right engine high? I'm not sure what I missed.

When turning into the dead engine, there’s a tendency to overbank as the plane will yaw towards the inoperative engine.

Re: United B772 at Denver on Feb 20th 2021, engine inlet separates from engine

#109

Earlier quoted context omitted.

One thing that sets software apart from other engineering disciplines is that they are grounded in physics (bits running on a semiconductor doesn't matter for this discussion) and have been around (in some form) for thousands of years. How do we know if a design is sound? We can check it by doing the math. How do we know if a program is sound (what does that even mean? There's our first problem)? Well, we rely on a l…

I'm wading into waters that are way over my head here, but my understanding is that it is possible for software to be provably correct, in the mathematical sense of "proof." I'm well aware of the admixture of folklore, experience, and caffeine-fueled inspiration that constitutes much of the software that runs our world.

There's work going on in formal verification but it has many limitations.

I'd also point out that in MechE/CivE fields, you're still dependent on materials (and maintenance) working as advertised. It's also often the case that operating conditions just end up being different from what was designed for or certain failure modes weren't considered. See, e.g. the Citibank Building in NYC http://www.slate.com/blogs/the_eye/2014/04/17/the_citicorp_t...

Re: United B772 at Denver on Feb 20th 2021, engine inlet separates from engine

#110
post #88

Earlier quoted context omitted.

You can hear the fire alert going off before the mayday. The fact that they requested a left turn at first it meant the controller knew the right engine was out and they'd need left turns to come in. Always find the level of training impressive and I'm glad they made it back safely. Aviate, Navigate, Communicate

I don't follow how the right engine being out means left turns. Seems like you'd have extra thrust on the left side and you'd want to make right turns. They wanted to keep the right engine high? I'm not sure what I missed.

That's exactly the problem, turning too heavily into the side of the dead engine can introduce a situation where it's impossible to pull out of that turn.
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