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

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

#181

Post by dmos62 »

almost_usual wrote: post #144
GekkePrutser wrote: post #135

That's crazy, in the Netherlands today there was another flight that dropped engine parts (much smaller though, they're said to have been turbine blades) that hit cars and people. It was also an airliner (747-400). Considering how rare an occurrence is, it's really weird to have both happen on the exact same day. https://www.airlive.net/breaking-turbine-blades-of-a-boeing-... By the way I'm surprised that fire keeps…

Poisson distribution, higher probability of short periods between failures than long ones.

Anyone care to elaborate? I don't understand what he means, but I feel like this is an interesting thread to pull.

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

#182

Post by [deleted] »

mannykannot wrote: post #162
chrisseaton wrote: post #20

Earlier quoted context omitted.

They could go faster with a single larger engine. Why do you think they went with two engines instead of a single larger engine? Redundancy.

While redundancy makes it a moot issue, if I am not mistaken, 777s already use some of the most powerful engines available. As for how fast they fly, I believe it is mostly set by the speed of sound.

[deleted]

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

#183

Post by mannykannot »

chrisseaton wrote: post #166
mannykannot wrote: post #162

Earlier quoted context omitted.

While redundancy makes it a moot issue, if I am not mistaken, 777s already use some of the most powerful engines available. As for how fast they fly, I believe it is mostly set by the speed of sound.

Yes they use two of the most powerful engines... and just one of those is more than enough to fly the plane just fine almost as fast as they are allowed to... so why else would they have two of them if not redundancy? Fundamentally people can look it up themselves - 'ETOPS' - the redundancy requirement is a written regulation.

I think it should be obvious that I am responding to the claim "they could go faster with a single larger engine." no-one is arguing against redundancy (in which matter, ETOPS is just one aspect.)

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

#184

Post by azalemeth »

dmoy wrote: post #134

That quoted ground observer. Do they work for the NTSB or something? I am 110% certain that if I saw a plane on fire in the sky, I would not have the presence of mind to remember the term "cloud deck", let alone the rest of those details. Ground observer: "Good sir, I do say that the cloud deck was quite low so I didn't get a good look, but the engine was mildly louder than usual, and possibly had smoke, but perhaps…

It's very likely that they're an AvHerald reader. It's the absolute de facto gold standard website in its field, and sensationalism and drama is not appreciated -- a large chunk of the usual audience are aviation professionals. My dad was a pilot, and I've got some few hours myself. You can bet that if either of us watched this event happen, we'd mentally be documenting it as best as we possibly can, both to try to predict any useful information (e.g should we try to move!), and for any subsequent investigation.

The excellent safety record of aviation originates from a detailed and pedantic paper trail that is written in blood. It's by learning as much as possible from every incident, without fear of censure or blame, that makes the skies safer for everybody.

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

#185

Post by hu3 »

starpilot wrote: post #95
hu3 wrote: post #60

Earlier quoted context omitted.

General software requirements can change drastically in a short period. Heck one of our clients requested major parts of our solution to be rebuilt for the third time within 6 months to accommodate the whims of their new leadership. You don't see that happening with aviation software where requirements are set in stone.

So raise the price of the software so that you can afford more/better software engineers, to produce a more robust and flexible project. Then it'll be aerospace quality, aerospace costs.

So your solution is to charge more and throw more engineers at the problem? Sounds like one of my ex-bosses.

Apple does that and they couldn't be further apart from aerospace engineering quality. Their software and hardware has been historically littered with problems and bugs.

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

#186

Post by willyt »

hnburnsy wrote: post #81
infodocket wrote: post #26

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...

EMERGENCY- A distress or an urgency condition. DISTRESS (MAYDAY)- A condition of being threatened by serious and/or imminent danger and of requiring immediate assistance. URGENCY (PAN-PAN)- A condition of being concerned about safety and of requiring timely but not immediate assistance; a potential distress condition.

“Declaring an emergency” is US specific. The rest of the world doesn’t recognise this phrase you have to use either “Mayday” for immediate danger to life or “Pan Pan” for less severe problems. As I understand it, “Declaring an emergency” is the equivalent of a Mayday and the US is very slowly switching away from this non standard phraseology.

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

#187

Post by s1artibartfast »

pedrocr wrote: post #21
JCM9 wrote: post #7

The press will make a big deal out of this because of the spectacle of parts falling on people’s lawns... but other than that this looks like a fairly routine engine out situation. Nice job by the crew.

Uncontained engine failures are a big deal. Exactly because they're a risk to the plane, as debris can cause other failures, and a risk to people on the ground. Engines are specifically tested to see if they can contain these failures. This doesn't seem routine at all.

They are both a big deal and expected. 3-4 happen per year and this is why pilots train for them.

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

#188

Post by [deleted] »

mannykannot wrote: post #183
chrisseaton wrote: post #166

Earlier quoted context omitted.

Yes they use two of the most powerful engines... and just one of those is more than enough to fly the plane just fine almost as fast as they are allowed to... so why else would they have two of them if not redundancy? Fundamentally people can look it up themselves - 'ETOPS' - the redundancy requirement is a written regulation.

I think it should be obvious that I am responding to the claim "they could go faster with a single larger engine." no-one is arguing against redundancy (in which matter, ETOPS is just one aspect.)

[deleted]

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

#189

Post by Zelphyr »

secfirstmd wrote: post #54
IgorPartola wrote: post #25

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…

They figured that little “Breaking News Alert!” out during 9/11, during which it was useful, but not at all after. I remember when Jason Priestly got into a car accident and they started throwing those alerts up. I realized then, “ok. Now they’ve jumped the shark”

The only thing that amazes me at this point is that it is apparently still effective enough that they keep doing it.

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

#190

Post by azalemeth »

xxpor wrote: post #18
alkonaut wrote: post #13

Lucky it didn’t happen half way. Could have been several hours on one engine and the other one shaking and on fire.

Luckily flight plans are always required to be within a certain number of minutes of a place to land, and are certified to operate on one engine for that period. https://en.m.wikipedia.org/wiki/ETOPS

Very rudely, I'd like to mention the popular backronymn for ETOPS: "engines turn or passengers swim"...
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