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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

#41

Post by pedrocr »

JCM9 wrote: post #39
pedrocr wrote: post #21

Earlier quoted context omitted.

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.

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.

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

#42

Post by emmanueloga_ »

"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 inspection should be able to catch...

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

#43

Post by ghaff »

chrisseaton wrote: post #20
Sn0wCoder wrote: post #19

Earlier quoted context omitted.

Come on, we all know so they can go faster.

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.

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.

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

#44

Post by Waterluvian »

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.

I think you're both right. I think it's routine in that once the disaster occurred, the emergency procedures to get the plane safely landed were executed without issue.

I'm guessing kind of like firefighters describing a call as a routine, by the books operation.

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

#46

Post by Dirlewanger »

just_steve_h wrote: post #30

I worked at a Large Internet Infrastructure Company for a long time, and saw software development practices that made my hair curl. All I could think was, "Gee, I'm glad we're not working on aviation software!" Seriously, though: software "engineering" could actually earn the name, if we had rigorous professional standards, regulatory oversight, and product liability.

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 large compendium of heuristics that are based on nothing but experiences compiled over the past ~60 years. Also, that compendium is constantly being added to. Also, virtually everyone disagrees on what should/shouldn't be in this compendium.

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

#48

Post by Pasorrijer »

disantlor wrote: post #27
mrfusion wrote: post #23

Earlier quoted context omitted.

How do you account for oceans?

i think in part by having more than 2 engines on those flights

Very few in service aircraft in commercial passenger fleets have more than two engines, and even the ones with more than two engines have modified ETOPS rules to comply with.

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

#49

Post by ceejayoz »

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…

Failures happen. So do mistakes. We design planes to be resistant as a result.

There are many engine issues that would not be visually apparent. Metal fatigue in the turbine blades, a bolt that’s the wrong size for its hole. Aviation has seen it all.

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

#50

Post by londons_explore »

ortusdux wrote: post #36

I have wondered in the past if the benefits of a 'jettison damaged engine' feature would outweigh the risks.

I suspect most airframes dont have sufficient spare strength to handle the imbalanced forces of an engine on one wing but not the other during flight.
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