Wow! Amazing escape for the people on this flight!!!

[SaparotRob]

Just did a quick Wiki. 777-300ER or possibly 777-200LR.
I should have known better. In my defense, I just woke up and haven't had the all important 3rd cup of coffee.

 

[FLYBOYJ]

B-747-400, B747-8(?), B777-???
I thought a carrier would pretty much contract the same manufacturer for engines to simplify logistics.

From their website;

https://www.koreanair.com/us/en/in-flight/aircraft

 

[SaparotRob]

From their website;

View attachment 613626

https://www.koreanair.com/us/en/in-flight/aircraft

I actually would read this stuff on board their flights from their literature. Long flight.
I think I can write off the freighter version.

 

[FLYBOYJ]

I actually would read this stuff on board their flights from their literature. Long flight.
I think I can write off the freighter version.

777-300ER has GE90-115BL engines

 

[SaparotRob]

777-300ER has GE90-115BL engines

Thanks bro'! We'll be eventually flying to Thailand on Korean. We got flyer miles mahk mahk with them.

 

[pbehn]

That will be determined once they know how much damage is discovered and will only be determined by a thorough inspection, not by glancing at a few photos.

In the crazy world of finance and insurance, it may be scrapped, it may be repaired and put back into service, my money is on it being repaired because it is insured and never flying again because it isn't needed.

 

[FLYBOYJ]

In the crazy world of finance and insurance, it may be scrapped, it may be repaired and put back into service, my money is on it being repaired because it is insured and never flying again because it isn't needed.

The aircraft is a bank asset and moneymaker for them. Unless it's in their monetary interest for it to be scrapped, every effort will be made to put it back in service. In a news conference yesterday the NTSB said damage to the rest of the airframe was light.

 

[MIflyer]

From Avweb:

NTSB chairman Robert Sumwalt updated the agency's investigation of the incident involving United Flight 328, which lost an engine on departure and made an emergency landing back at Denver. While stressing that the investigation is in the very early stages, Sumwalt said that the indications are that metal fatigue led to the failure of one of the Pratt & Whitney PW4077's first-stage fan blades, of which there are 22.

"Two blades found fractured," he said. "One at the root while the adjacent blade was fractured at mid span. The indications are consistent with the blade [broken at mid span] is that it was hit by the other blade." Portions of one blade were found in the engine containment ring at the 1 o'clock position. As widely reported, the 777 left a debris field a mile long; Sumwalt says that the NTSB is working with local law enforcement to recover as much of the missing engine and airframe as possible.

Sumwalt commented on the other damage visible. "There was damage to the composite wing-to-body fairing, and there were dings and nicks in other places on the wing." Sumwalt stressed that at this stage is appears the damage is limited to nonstructural components and that no systems appear to have been in jeopardy nor was the Boeing's pressure vessel breached.

United 328 had departed Denver for Honolulu and had been cleared to 23,000 feet. About 4 minutes after takeoff, climbing through 12,500 feet and going 280 knots, "there was a loud bang and increased vibration from the #2 engine," Sumwalt said, based on a preliminary read on the cockpit voice recorder and flight-data recorder. Sumwalt also confirmed that the fire handle for the right engine had been activated and both fire bottles discharged. Video of the aircraft returning to Denver shows the engine power section glowing, though Sumwalt confirmed that the fuel supply had been shut off as part of the shutdown procedure.

The 777-200 landed without further incident. The crew decided that an emergency egress was not needed back at Denver so the 229 passengers deplaned normally.

 

[buffnut453]

I still say it could have been much worse, and that everyone was lucky that engine debris didn't enter the pressure cabin.

 

[MIflyer]

Well, it is a good thing that the airframe damage was not worse but even if the pressure cabin had just been breached it would just mean that the cabin outflow valve would have to close off more to maintain the cabin pressure.

I understand that on the 787 they have gone to using electrically driven pumps to pressurize the cabin rather than using engine bleed air. Aside from making the cooling task easier, this also reduces the need for ram air, improves engine efficiency, reduces weight by eliminating the bleed air ducts running from the engines to the fuselage, and improves safety by not having to worry about a bleed air duct failure cooking something. But I am sure there is something wrong with the idea!

 

[buffnut453]

Well, it is a good thing that the airframe damage was not worse but even if the pressure cabin had just been breached it would just mean that the cabin outflow valve would have to close off more to maintain the cabin pressure.

I understand that on the 787 they have gone to using electrically driven pumps to pressurize the cabin rather than using engine bleed air. Aside from making the cooling task easier, this also reduces the need for ram air, improves engine efficiency, reduces weight by eliminating the bleed air ducts running from the engines to the fuselage, and improves safety by not having to worry about a bleed air duct failure cooking something. But I am sure there is something wrong with the idea!

I was more concerned at the prospect of high-speed shrapnel flying around a metal tube containing densely-packed human life forms.

 

[GrauGeist]

It's not common for debris from an uncontained engine failure to breach the pressure cabin on an aircraft, but it can happen, like the Southwest incident back in 2018, when debris broke a window and partially sucked a woman out of the cabin.

In that case, it was a Boeing 737 NexGen with CMF56 engines.

 

[MiTasol]

There's no way you can make that determination from looking at those photos. Yes the jet took a beating and also had an overweight landing on top of this, but until a through inspection is completed there's no way you can even come close calling this a "write-off." I've seen a lot worse fixed...

Like skippy's 747 at Bangkok, #3 pylon into the wing etc but skippy rebuilt it, reportedly for far more than replacement cost, so that they could pretend they have never lost an aircraft. Too bad records and photos exist of their many hull losses and total loss (aircraft and pob) crashes. In many ways that accident mirrored their first jet crash in 66? - the 707 at Singapore and the first root cause was the same - thou shalt not waste fuel by doing a go-around when you screw up your approach.

As for the 777 being a write-off - even in this climate that is most unlikely.

As an important aside if you want to see the extent of the 777s operating safety margins look for photos and video from its certification "worst case scenario takeoff with engine failure at rotation while at max takeoff weight" from Lhasa in Tibet in mid summer.

Even with the high power loss due to the density altitude it still climbed out at close to the normal angle of attack.

 

[MiTasol]

I still say it could have been much worse, and that everyone was lucky that engine debris didn't enter the pressure cabin.

Given the containment ring is supposed to catch any debris and prevent fuselage penetration, and during certification one blade is exploded off to make sure it works there was minimal chance of fuselage penetration. The failure of the adjacent blade presumably introduced vibration which, combined with the cowling damage from containing the failed blade, caused the cowlings to fail and separate.

The belly damage appears primarily, maybe completely, to be to the composite non structural aerodynamic fairings and was almost certainly caused by the cowlings - not the blade segments.

If you poke around the net you can find videos of engine certification tests, blade failure, bird ingestion, etc and some are very dramatic and the finally certified cowling contains all the damage. It will be interesting to see why this cowling failed. The second blade? corrosion? fatigue? other factors? Only time will tell. If deemed necessary new certification standards or inspection procedures will be introduced.

Certification and inspection procedures changes have prevented any engine debris from entering fuel tanks since the 1985 Manchester accident.

For a minor overview of that accident and the initial changes that resulted from that accident go to https://www.flightsafety.org/fsd/fsd_feb89.pdf

You will note on page 6 some of the US mandated modifications which were never applied to the Concorde.

Not covered in this article are any of the mandatory changes to seat coverings, seat bolsters, cabin linings, etc, requiring the rapid installation of fire retardant materials that produce no toxic fumes. I cant be sure but I seem to remember the floor level exit lighting regulations came out of this accident as well. Given I am old this may not be correct.

 

[MiTasol]

Well, it is a good thing that the airframe damage was not worse but even if the pressure cabin had just been breached it would just mean that the cabin outflow valve would have to close off more to maintain the cabin pressure.

I understand that on the 787 they have gone to using electrically driven pumps to pressurize the cabin rather than using engine bleed air. Aside from making the cooling task easier, this also reduces the need for ram air, improves engine efficiency, reduces weight by eliminating the bleed air ducts running from the engines to the fuselage, and improves safety by not having to worry about a bleed air duct failure cooking something. But I am sure there is something wrong with the idea!

It is interesting that the 787 uses a pressurization system that is similar to the Douglas DC8 and 707. Those used bleed air instead of electricity for power but that bleed air drove the cabin compressors and was then dumped overboard. Only air from the nostrils under the nose of the DC8 and those big holes in the front of three engine pylons entered the cabin. In those days the bleed air was considered too likely to be contaminated from engine oil seal leakage to be allowed in cabins.

I have no personal knowledge of the 787 so I wonder what is used for wing and tail ice protection if not bleed air. Titanium bleed air ducts are actually very light (though bulky) and all of the electrical de-icers I have worked on are both heavy and unreliable.

Hopefully we have a 787 AMT on this forum who can answer this question.

 

[MIflyer]

The B-52 has a Hopcalite filter in the bleed air duct to the air conditioning system that is designed to catch particulates as well as convert any hydrocarbons into HCL. It seems to be needed only when there are leaky fuel manifolds on the engines.

 

[FLYBOYJ]

Like skippy's 747 at Bangkok, #3 pylon into the wing etc but skippy rebuilt it, reportedly for far more than replacement cost, so that they could pretend they have never lost an aircraft. Too bad records and photos exist of their many hull losses and total loss (aircraft and pob) crashes. In many ways that accident mirrored their first jet crash in 66? - the 707 at Singapore and the first root cause was the same - thou shalt not waste fuel by doing a go-around when you screw up your approach.

As for the 777 being a write-off - even in this climate that is most unlikely.

As an important aside if you want to see the extent of the 777s operating safety margins look for photos and video from its certification "worst case scenario takeoff with engine failure at rotation while at max takeoff weight" from Lhasa in Tibet in mid summer.

Even with the high power loss due to the density altitude it still climbed out at close to the normal angle of attack.

I live in Colorado, this happened about 15 miles south of my location. The NTSB mentioned the other day the damage to the airframe was minor. On some of these aircraft this is a non issue, especially during our cold winter days,

 

[MIflyer]

A view from the ground:

 

[GreenKnight121]

There are several videos of debris landing on the ground:


Debris falls from plane during emergency landing near Denver

https://www.koaa.com/debris-from-co...mfield-neighborhood-plane-lands-safely-at-dia

 

[MIflyer]

That's amazing! Why would anybody be pointing a camera at the sky anyway? Was it raining down so long they startd taking pictures of it?