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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

#81

Post by hnburnsy »

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.

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

#82

Post by danaliv »

m00dy wrote: post #3

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

To a first approximation, if it takes X thrust to stay aloft, the engines produce a combined total of more than 2X, and there is a speed above which the rudder produces enough aerodynamic force to maintain directional control.

If you want to get into the nitty gritty, look up multiengine airplane type certification requirements.

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

#83

Post by ghaff »

chrisseaton wrote: post #52
ghaff wrote: post #43

Earlier quoted context omitted.

Not clear to me that you'd design a commercial turbofan aircraft with one engine if you eliminated reliability requirements. You need to feed air to the engine and, to the degree you have wings, might as well have 2 engines.

The idea that the engines need to sit on the wings like they do is something seems important, because it's so often done, but is actually not necessary. You can put a single engine in the tail, or on top of the cabin, or on the top of the cockpit, or underneath. They go on the wings because when you need two (for redundancy) it's a good place to put them for balance, and because it makes them nicely accessible for ma…

Of course military aircraft have different requirements (and many have just one engine in the tail). Certainly I'm not enough of an aero/astro engineer to know if, positing a perfectly reliable engine, you'd mount just one somewhere on the fuselage.

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

#85

Post by alkonaut »

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

Indeed. The scary part here isn’t the loss of (function in) one engine, it’s structural issues, fire and so on. A violent engine failure can give a whole range of problems beyond just the loss of the engine. It would likely have been ok even half way to Hawaii, but it would have been scary.

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

#87

Post by terramex »

emmanueloga_ wrote: post #42

"the right hand engine's (PW4077) inlet separated associated with the failure of the engine." This description is rather nonchalant but how can this possibly happen!? May this be related to the age of the aircraft? "Ground observers reported hearing the sound of an explosion like bang, smoke and saw the debris falling down." I mean, an engine about to explode sounds like the kind of thing that a routine pre-flight in…

It looks like of of the fan blades detached and ripped cowling off. Such engine defects are usually not detectable during routine pre-flight inspection, for that you need to disassemble whole engine, check bearings, do x-ray inspection of turbine to look for metal fatigue or micro cracks etc.

Two years ago there was very similar incident, also Boeing 777 with PW4000 engine: http://aerossurance.com/safety-management/ndi-failures-b777-...

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

#88

Post by xvf22 »

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...

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

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

#89

Post by artificial »

divbzero wrote: post #74
larkinrichards wrote: post #11

I really appreciate focused news sites like avherald. Just the facts, a collection of photos and videos, straightforward. The video of the landing & the passengers cheering—- that huge sigh of relief. Brings a smile to my face.

The straightforward captions are also delightful: > The aircraft seen in flight > The engine inlet in a garden > Engine debris on the Broomfield soccer field

It would be amusing if it turned out to be machine vision transcriptions.

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

#90

Post by shiny »

pintxo wrote: post #59
xnx wrote: post #5

Earlier quoted context omitted.

Amazingly, I believe planes are designed/certified to do everything (e.g. take off fully loaded) with only a single working engine.

And if they loose the remaining one, all goes south: https://www.youtube.com/watch?v=zn1a2lSk_UI&feature=emb_logo

Not if you have Sully in the cockpit [1]. They can still glide.

[1]: https://en.wikipedia.org/wiki/Chesley_Sullenberger

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