UA flight #328 loses engine over Broomfield CO.

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He = "Captian Joe". In his video, was he wrong or off in any way of what he said about this indedent and how to handle emergency in-flight situations? If he was off or wrong, then who's the more expert that shows he was wrong in the information he gave in the video.

This is why I’m actaully trying to defend “Captain Joe”. That video is more thorough (and accurate) than probably 99.99% of the news article out there on this situation, and yet still it’s all complaining.

If someone has a better example explaining to a layperson (who his channel caters to) what the pilots and ATC do in a situation like this, I’d love to see it.
 
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I was referring to UA328.
The DC10 had hydraulics cut as far as I know by fan disintegration.
But, I absolutely agree. Not sure how you contain everything.
On the DC-10 it was a Fan disk. That is a huge wheel that all the fan blades are rooted into and spins at very high rpm's,. When it fractured into pieces it then flew out of the engine. It wasn't a simple blade, it is like a heavy flywheel like thing and the amount of kevlar like material needed to contain it would be extremely bulky and take up a lot of space, at the speed that it rotates the energy is almost like a rocket going through the engine. I never want a seat on a plane near the side of or close to the rear of a jet engine, when something lets go that is heavy with in the engine its coming out, nothing will contain it.
Here is a report about the DC-10 incident.
 
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This is why I’m actaully trying to defend “Captain Joe”. That video is more thorough (and accurate) than probably 99.99% of the news article out there on this situation, and yet still it’s all complaining.

If someone has a better example explaining to a layperson (who his channel caters to) what the pilots and ATC do in a situation like this, I’d love to see it.
I personally don’t depend on the media for any serious analysis. It wouldn’t be hard to beat them accuracy wise.

The best way to know what happened and what caused it is to wait until the report comes out ( any incident/accident ) but that takes time and most want to know before that. I am guilty of that too.

I am glad nobody got hurt ( air or on ground ) and that our airline doesn’t have those engines because we just had a whole pile of 737 Max grounded and when we finally got the go ahead to fly them our country started discouraging people from flying ( pandemic ). luckily we won’t have to potentially ground any of our 777s.

my country has not had airline specific aid like most G7 countries, we are on our own burning through millions per day even with 1/3 of the fleet parked long term and mass layoffs and pay cuts.

my airlines preferred wide body ( during pandemic ) is the 787, not the 777 ( too big ).

little off topic but the only transportation device that causes me concern “sitting beside” is driving beside transport trucks on highways ( multi lane ). Far too many wheel assemblies have come loose due to poor maintenance ( or tires blowing off ).
 

MolaKule

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On the DC-10 it was a Fan disk. That is a huge wheel that all the fan blades are rooted into and spins at very high rpm's,. When it fractured into pieces it then flew out of the engine. It wasn't a simple blade, it is like a heavy flywheel like thing and the amount of kevlar like material needed to contain it would be extremely bulky and take up a lot of space, at the speed that it rotates the energy is almost like a rocket going through the engine. I never want a seat on a plane near the side of or close to the rear of a jet engine, when something lets go that is heavy with in the engine its coming out, nothing will contain it.
Here is a report about the DC-10 incident.
This has Already been explained in post #139.

ExhaustGases said:
...and the amount of kevlar like material needed to contain it would be extremely bulky and take up a lot of space, at the speed that it rotates the energy is almost like a rocket going through the engine...

Technically incorrect on all counts. The Containment Ring is a series of thin composite layers of titanium-carbon fiber-titanium-carbon fiber with each layer of Kevlar-carbon fiber oriented at 45 degrees relative to the other layers; this orientation increases the strength of the Containment Ring without adding more layers and weight.

A separated blade has rotational, translational, tangential, and pressure components so the resulting kinetic energy vector has four vector components.

You design and analyze the Containment Ring (and any other aircraft part) for worst case (highest energy, highest stress) scenarios. See post #122.
 

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NTSB confirmed 1 and 1/2 blades separated... if the advertise weight of each hollow titanium blade is 35lbs then its possible the engine shook itself to destruction minus 50lbs of weight instead of exploding... my observed speculation points to a external fire fed from the pylon to engine junction and not a internal compressor fire... typically jet engines are supported by just 3 mounts so they are allowed to move about...

UA328Boeing2.JPG
UA328PW4.JPG
 
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The containment ring looks good but something did go through the fuselage. Was it one of the moving parts of the back part of the engine, or part of the engine cowling? Fortunately it didn't enter the passenger compartment and the altitude was low so decompression wasn't an issue.
 
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The containment ring looks good but something did go through the fuselage. Was it one of the moving parts of the back part of the engine, or part of the engine cowling? Fortunately it didn't enter the passenger compartment and the altitude was low so decompression wasn't an issue.

It wasn't technically the fuselage.

Sumwalt also acknowledge damage to the underbody of the aircraft, but says the damage was not structural. The part damaged is a composite fairing that smooths out the plane to make it more aerodynamic.​
 
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Emergency Airworthiness Directive (AD) 2021-05-51 is sent to owners and operators of Pratt & Whitney Division (PW) PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 model turbofan engines.

(g) Required Actions
(1) Before further flight, perform a thermal acoustic image (TAI) inspection of the 1st-stage LPC blades for cracks using a method approved by the FAA.



 

MolaKule

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I am still puzzling over the source of the fire, since the fuel pumps were shut down.

Normally, the oil is cooled at the heat exchanger by the extremely cold fuel and this heat exchanger sits on the engine (core) casing right behind the fan case with its associated plumbing.

Just a theory, but I'm thinking when the flan blade debris let loose this debris cut the oil lines, which subsequently flowed oil on the hot rear case igniting the oil.
 
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Might be the reason why JAL, ANA and KAL have grounded their 777s with the same engine. Nothing wrong with having a abundance of caution

Yes, but from what I understand of aviation safety, one of the primary goals in accident investigation is to implement solutions that will prevent repeat accidents of the same nature.

UA1175 occurred in 2018. JA8978 occurred at the end of last year, and now there is UA328.

Look at the aftermath photos of each engine, and they've all experienced remarkably similar failures. Mix them up without captions, and it would be hard to assign any of them to a particular incident.

My question was from the standpoint of how things have arrived to where they are, given that record. Were the dots not connected?
 
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Astro14

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I am still puzzling over the source of the fire, since the fuel pumps were shut down.

Normally, the oil is cooled at the heat exchanger by the extremely cold fuel and this heat exchanger sits on the engine (core) casing right behind the fan case with its associated plumbing.

Just a theory, but I'm thinking when the flan blade debris let loose this debris cut the oil lines, which subsequently flowed oil on the hot rear case igniting the oil.
I'm puzzled by the persistent fire as well.

In general, during a severe damage/fire/failure shut down of an engine, the crew pulls the fire handle for that engine.

The fire handle does the following:
1. shuts off fuel at both the fuel control shut off valve and the spar valve (in the pylon that holds the engine to the wing)
2. shuts off hydraulic fluid
3. shuts off bleed air from the engine
4. shuts off generator electric (field) supply
5. arms fire bottles to that nacelle.

So, I see several possibilities for the persistent fire:
1. The fire handle was not pulled*, since the engine was still making power (I consider this unlikely, but we don't yet know)
2. A spar valve did not completely close, so fuel was still going to the engine
3. The fire was from the 20-25 quarts of oil left in the engine as it continued to turn, and the oil pumps continued to operate.

Of the fire possibilities, I'm on the oil side of the thinking.

By the way, the oil cooler is more of a fuel warmer than just oil cooler. In very cold conditions, the fuel gets close to gel temperature, and warming it up dissolves any paraffin so that the engine keeps running and the filter and/or fuel control don't get clogged up.



*We have been slowly changing how we assess engine damage and our response to damage as a result of evidence and analysis that showed that 80+% of the engines that we shut down (and pulled the fire handle) were actually capable of producing thrust. So, where we were once very aggressive in just shutting down an engine with malfunctions, like a compressor stall, and pulling the fire handle, we are now more thoughtful about the assessment.

The assessment includes the following: rotation, vibration, and fire (the verbiage in the flight manual is paragraphs long, but I like to keep things simple when teaching or discussing them). So, if the engine is still rotating, and there is no excessive vibration or fire, we are encouraged to try a restart and operate the engine.

Compressor stall (I've had perhaps a hundred in my previous career, and zero in 23 years of airline flying) may clear at reduced thrust, or it may take a shut down to achieve balance between N1 and N2 rotors (N3 in the case of the RB-211 on the 757) and allow normal operation. We, as an industry, had shut down a lot of compressor stalls, pulled the handle, and left those engines off.

Well, when it's 3 hours to Hawaii on one engine, pulling the handle on an engine that was actually able, even likely, to run correctly once restarted becomes a less than optimum decision.

So, while it's too early to know, I am really looking forward to the report on this from a crew perspective - what were the cockpit indications? The Captain is a Line Check Airman - an instructor in the airplane, so his thinking should reflect the latest evolution in our approach.

What did they see?

What did they decide?
 
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Astro14

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Might be the reason why JAL, ANA and KAL have grounded their 777s with the same engine. Nothing wrong with having a abundance of caution

Easy to have an abundance of caution when a pandemic has created a surplus of airplanes and a company has multiple types (787, 767) to backfill the routes on which that airplane type (777-200A) was operating.

Pretty hard to have an abundance of caution when you operate one airplane type and a lethal flaw is found.

In 1999, the NTSB determined that two fatal (all on board killed) crashes of 737s were due to design flaws in the rudder PCU (the hydraulic actuator for the rudder). The 737 was built with a single rudder and single PCU, unlike 747, 757, 767, 777, even 727. The PCU was at fault in the United 585 crash in COS, which had been blamed on mountain rotor (wind) and in the USAIR 427 crash which had been blamed on pilot error.

There were several incidents involving 737 near loss of control, along with a few crashes at the time that the NTSB made this determination. They had tested the PCU, and found that when cold-soaked, the PCU could throw the rudder to full deflection without flight control input and that the rudder would stay there, no matter what flight control input was made.

Fatal design flaw in an entire fleet of aircraft. Fatal crashes. Just like the MAX, only, the design flaw wasn't discovered until about 8 years later, because the crashes had been blamed on something else at the time.

Still, a fatal flaw in the airplane that put everyone flying it at risk.

So, United grounds all 150 of their 737s. American, Delta, USAIR, Continental - all ground their 737s. All out of caution. Not even an abundance, just basic caution in light of the NTSB discovery.

But, the FAA allows other 737s to keep flying, despite the fatal crashes, these total losses. Hard to call that an "abundance of caution". One airline, in particular, was able to convince the FAA to keep flying the airplane with this flaw in the rudder, as long as they used different flap speeds to enable a crew to counter the possible rudder hard over with aileron. The "crossover" speed is the speed at which change in AOA allows rudder to overpower aileron - so, the fix was to fly above that speed for each flap setting and hope the crew responds quickly if the flawed PCU slams the rudder full stop.

Fatal, serious flight control design flaw in the airplane's rudder, but you guys have three years to get new PCUs installed.

So, the 737 flew, with one airline operating a full flight schedule of 737, despite the design defect and despite the deadly history of that defect.

Where was the "abundance of caution" then? Oh yeah, it cost some airlines a LOT of money, so, sure ground them. But it would've cost that one airline even more, since they only had one airplane type...so, yeah, caution can be waivered and put aside, rather than lose money...in certain cases...when it's convenient to do so...
 

Astro14

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Glad everything turned out well and no one was seriously hurt. Testament to engineering and of course, it helps when you have a well trained crew.
Much more a testament to crew, in this case, I think, though the 777 is a great airplane.

The engineering failed (the blade broke) but the crew handled it well. A calm, thoughtful set of decisions, and uneventful landing as a result.
 
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Much more a testament to crew, in this case, I think, though the 777 is a great airplane.

The engineering failed (the blade broke) but the crew handled it well. A calm, thoughtful set of decisions, and uneventful landing as a result.
No doubt, the crew handled it extremely well, a plane is only as good as its pilot(s). Almost a similar situation with the Qantas A380 engine failure a while back. Even more so the Gimley glider incident and the air transit incident though they weren't the case of a fan blade breaking.

Still. I believe aircraft, next to the space shuttle are the greatest feats of engineering when it comes to commercial/military transport. The amount of stress tests and variables that go into aviation engineering are staggering. You flew the F-14, I don't have to sing praises to ya ;)
 
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