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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

#371

Post by colechristensen »

underseacables wrote: post #336
colechristensen wrote: post #329

Earlier quoted context omitted.

The plane landed and didn’t blast enormous holes with ejected compressor blades. That’s a successful failure.

Is that what happenes when The fan blades fly off and hit the airplane?

Pieces on the inside of jet engines are spinning between 2,000 and 12,000 rpm. They should all be properly contained in an airliner, but before that was the case of one fan blade broke and hit the plane it could look like a bomb blew an enormous hole in the side of the plane. These small pieces have a huge kinetic energy because they’re spinning so fast.

Nothing bad happening, everyone uninjured and a plane making an orderly airport emergency landing is many layers of safety systems all working properly.

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

#372

Post by mathgenius »

silvestrov wrote: post #364
laurent92 wrote: post #214

Earlier quoted context omitted.

Random = clusters happen. In fact, mathematicians were hired during the Battle of England to estimate whether the Germans were aiming for specific buildings (“why is there a cluster of bombs around this church???” or around some secret offices) or just spreading randomly. Verdict: They weren’t aiming, it was random chance that bombs made some clusters onto some buildings. This is what random looks like: No even distr…

I've tried to find a non-clustering pseudo-random function. Anybody knows the name or urls of those?

Maybe quasi-random is what you are looking for?

https://www.gnu.org/software/gsl/doc/html/qrng.html

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

#373

Post by fit2rule »

baptistejamin wrote: post #351

I don’t really understand why this information is now #1 on HackerNews. Boeing 777 engines are the world’s largest turbofans and pw4000 Engine, involved in this explosion is in production since the 80/90, and is already used on other Airframes like a330. I know this accident looks impressive, but engine explosions like this one are things that happens years over years. On Airbus a380, similar explosions occurred. Thi…

>I don’t really understand why this information is now #1 on HackerNews.

Because HN readers invest, and this could have given some of them time to short Delta/Boeing stock ..

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

#374

Post by jeffrallen »

lrossi wrote: post #233
azalemeth wrote: post #184

Earlier quoted context omitted.

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 p…

I can draw some parallels between that and a healthy SRE culture. Except for the casualties, of course. Wondering if the first SREs who created the guidelines had aviation industry experience.

Brent Chapman was one, and he worked in volunteer search and rescue.

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

#375

Post by silvestrov »

mathgenius wrote: post #372
silvestrov wrote: post #364

Earlier quoted context omitted.

I've tried to find a non-clustering pseudo-random function. Anybody knows the name or urls of those?

Maybe quasi-random is what you are looking for? https://www.gnu.org/software/gsl/doc/html/qrng.html

This is exactly it! Many thanks for the name.

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

#376

Post by technicolorwhat »

chovybizzass wrote: post #348

...aaaaaaand that's why i refuse to fly.

Fellow scared dude here. I still fly even though I am terrified. Its annoying but don't let it stop you from seeeing all the beautiful places in the world. Usually I just get absolutely drunk, fake being sober going trough control and unfortunately that kinda works. Annoying hangover though. hahah. Wish I could do sth about it!

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

#377

Post by touisteur »

underseacables wrote: post #336
colechristensen wrote: post #329

Earlier quoted context omitted.

The plane landed and didn’t blast enormous holes with ejected compressor blades. That’s a successful failure.

Is that what happenes when The fan blades fly off and hit the airplane?

Ugh look up QF-72 for an A380 Rolls-Royce engine containment failure...

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

#378

Post by touisteur »

throwawayboise wrote: post #306
codingdave wrote: post #169

Earlier quoted context omitted.

Another way of looking at it is that after flying and accumulating 25 years of wear and tear without major incident, we now have seen a repeatable flaw that these aircraft may encounter due to their age.

Aircraft undergo regular preventative maintenance checks, with letter codes A - D. The D check being the most comprehensive, it occurs every 6-10 years and basically the entire aircraft is taken apart and inspected, looking for among other things anything like stress fractures, corrosion, unusual wear, etc. https://en.wikipedia.org/wiki/Aircraft_maintenance_checks#D_... A commercial aircraft does not just accumulate…

Beware of the dangers of preventative maintenance, where sometimes while replacing or inspecting or re-mounting inspected parts, the maintenance crew breaks something that was OK and probably going to be working fine for years.

But yeah, a D check is so expensive I've heard there's a habit of dumping the aircraft on less observing flying companies some thousand miles before it comes up...

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

#379

Post by thgaway17 »

terramex wrote: post #113

Almost identical incident happened 3 years ago - the same type (B777-200), the same engine (PW4077), the same operator (United Airlines), the same side (right engine), the same failure (unconfined engine failure). https://avherald.com/h?article=4b4e8ca7&opt=0 I would not be surprised if the whole fleet of this type/engine gets grounded for some time.

It was a bird strike.

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

#380

Post by mcdevilkiller »

touisteur wrote: post #377
underseacables wrote: post #336

Earlier quoted context omitted.

Is that what happenes when The fan blades fly off and hit the airplane?

Ugh look up QF-72 for an A380 Rolls-Royce engine containment failure...

Are you sure? That was an A330, and a failure on one ADIRU.
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