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DocLightning
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Re: United 1175 - Engine Cowling Fails

Wed Feb 14, 2018 9:34 pm

TWA302 wrote:
The in cabin video from the pax really shows how the fan blade loss really impacts the balance, even with the engine shut-down. Lots of vibrations/shaking. I can understand the fear they had. Even as a very frequent flyer, I would have been very uneasy too.


Especially 45 minutes out from the most remote archipelago in the world. (Easter Island is the most remote ISLAND in the world, but Hawaii is the most remote archipelago). 45 minutes is an awful lot of drink to cover to get to tierra firma.
JAGflyer wrote:
Seeing as the flight was from SFO, I'm going to guess the cowling is somewhere at the bottom of the Pacific. How do they intend to find it seeing as an examination of it would probably help answer questions about what exactly happened.


They could go hunting, after all they do know exactly where the A/C was when the failure occurred. But given that they have the complimentary fracture surfaces for the relevant components, this might not be necessary.

What's interesting to me is that most blade-off events occur when the engine is at high RPM. With both this and the AF A380 that lost the entire fan, I find it a bit odd that the failures occurred at cruise. I guess there could have been a crack slowly propagating its way through the blade until it just gave there. I remember hearing an engineer at RR once say that a single fan blade on the Trent 800 exerts a force on the hub comparable to the weight of a diesel locomotive at 100% N1, so even at 60-75%N1 that you might have at cruise, that's still an awful lot of force, not to mention the forward torque from the aerodynamic forces that the blade is meant to produce (yes, I know this is a PW4000 but it's comparable to a Trent 800).
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codc10
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Re: United 1175 - Engine Blowout?

Wed Feb 14, 2018 9:57 pm

Western727 wrote:
reffado wrote:
As of 10/2016, N773UA had ~14800 cycles/81100 hours (as per an older a.net thread). Using the average cycles per year, should be close to 16000?


Thanks, reffado. Any updates on current TC and TT?


If UA were involved in active 777 retirements, or had any planned, I would expect a w/o, but absent major structural damage, I think it'll be repaired and returned to service eventually.

N773UA was at 16340 cycles and ~89720 hours. High # of cycles for a 777 of its vintage, consistent with its pattern of use as an A-market airplane (short international for its first 20 years, followed by domestic).
 
77H
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Re: United 1175 - Engine Cowling Fails

Wed Feb 14, 2018 10:03 pm

Well that didn't take long... As a poster jokingly said way up thread, all A.Net discussions around a mtx incident eventually lead to questions of write off. Bird strike? W/O, blown slide? W/O.

A few years ago BA had a T7 on fire at LAS. That plane eventually went back into rev service. This aircraft will see rev service with UA. There are only 19 77A's in their fleet and they fill a role no other aircraft can.

77H
 
wjcandee
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Re: United 1175 - Engine Cowling Fails

Wed Feb 14, 2018 10:16 pm

77H -- I was thinking the same thing. You said it very well.

Doc -- could have just been a blade or hub defect that ultimately gave way, as you speculate. Just because it USUALLY occurs at high RPM, it doesn't ALWAYS do so. Also could have ingested something. Or, something wasn't properly-secured and the engine ingested part of the cowl, leading to the blade damage. Although we can all venture EWAGs about the most-likely scenario, there are a number that are probably equally-viable given the limited info we have.
 
Max Q
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Re: United 1175 - Engine Cowling Fails

Wed Feb 14, 2018 11:00 pm

DocLightning wrote:
TWA302 wrote:
The in cabin video from the pax really shows how the fan blade loss really impacts the balance, even with the engine shut-down. Lots of vibrations/shaking. I can understand the fear they had. Even as a very frequent flyer, I would have been very uneasy too.


Especially 45 minutes out from the most remote archipelago in the world. (Easter Island is the most remote ISLAND in the world, but Hawaii is the most remote archipelago). 45 minutes is an awful lot of drink to cover to get to tierra firma.
JAGflyer wrote:
Seeing as the flight was from SFO, I'm going to guess the cowling is somewhere at the bottom of the Pacific. How do they intend to find it seeing as an examination of it would probably help answer questions about what exactly happened.


They could go hunting, after all they do know exactly where the A/C was when the failure occurred. But given that they have the complimentary fracture surfaces for the relevant components, this might not be necessary.

What's interesting to me is that most blade-off events occur when the engine is at high RPM. With both this and the AF A380 that lost the entire fan, I find it a bit odd that the failures occurred at cruise. I guess there could have been a crack slowly propagating its way through the blade until it just gave there. I remember hearing an engineer at RR once say that a single fan blade on the Trent 800 exerts a force on the hub comparable to the weight of a diesel locomotive at 100% N1, so even at 60-75%N1 that you might have at cruise, that's still an awful lot of force, not to mention the forward torque from the aerodynamic forces that the blade is meant to produce (yes, I know this is a PW4000 but it's comparable to a Trent 800).




They were a reasonable distance out but it doesn’t compare with the triple that diverted into the big island a few years ago on the way up from AKL to the west coast


They were on one engine for over three hours, not a comfortable feeling over the pacific
The best contribution to safety is a competent Pilot.
 
na
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 12:38 am

Max Q wrote:
They were on one engine for over three hours, not a comfortable feeling over the pacific


No way I´d fly on a Twin over the open Pacific. What a horror to depend on one engine on a old plane way past its prime for 3 hours.
 
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Spacepope
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 1:14 am

Max Q wrote:
DocLightning wrote:
TWA302 wrote:
The in cabin video from the pax really shows how the fan blade loss really impacts the balance, even with the engine shut-down. Lots of vibrations/shaking. I can understand the fear they had. Even as a very frequent flyer, I would have been very uneasy too.


Especially 45 minutes out from the most remote archipelago in the world. (Easter Island is the most remote ISLAND in the world, but Hawaii is the most remote archipelago). 45 minutes is an awful lot of drink to cover to get to tierra firma.
JAGflyer wrote:
Seeing as the flight was from SFO, I'm going to guess the cowling is somewhere at the bottom of the Pacific. How do they intend to find it seeing as an examination of it would probably help answer questions about what exactly happened.


They could go hunting, after all they do know exactly where the A/C was when the failure occurred. But given that they have the complimentary fracture surfaces for the relevant components, this might not be necessary.

What's interesting to me is that most blade-off events occur when the engine is at high RPM. With both this and the AF A380 that lost the entire fan, I find it a bit odd that the failures occurred at cruise. I guess there could have been a crack slowly propagating its way through the blade until it just gave there. I remember hearing an engineer at RR once say that a single fan blade on the Trent 800 exerts a force on the hub comparable to the weight of a diesel locomotive at 100% N1, so even at 60-75%N1 that you might have at cruise, that's still an awful lot of force, not to mention the forward torque from the aerodynamic forces that the blade is meant to produce (yes, I know this is a PW4000 but it's comparable to a Trent 800).




They were a reasonable distance out but it doesn’t compare with the triple that diverted into the big island a few years ago on the way up from AKL to the west coast


They were on one engine for over three hours, not a comfortable feeling over the pacific

How has the figure gone from 45 minutes to 3 hours for this incident?
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DarkSnowyNight
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 1:21 am

Spacepope wrote:
Max Q wrote:
DocLightning wrote:

Especially 45 minutes out from the most remote archipelago in the world. (Easter Island is the most remote ISLAND in the world, but Hawaii is the most remote archipelago). 45 minutes is an awful lot of drink to cover to get to tierra firma.

They could go hunting, after all they do know exactly where the A/C was when the failure occurred. But given that they have the complimentary fracture surfaces for the relevant components, this might not be necessary.

What's interesting to me is that most blade-off events occur when the engine is at high RPM. With both this and the AF A380 that lost the entire fan, I find it a bit odd that the failures occurred at cruise. I guess there could have been a crack slowly propagating its way through the blade until it just gave there. I remember hearing an engineer at RR once say that a single fan blade on the Trent 800 exerts a force on the hub comparable to the weight of a diesel locomotive at 100% N1, so even at 60-75%N1 that you might have at cruise, that's still an awful lot of force, not to mention the forward torque from the aerodynamic forces that the blade is meant to produce (yes, I know this is a PW4000 but it's comparable to a Trent 800).




They were a reasonable distance out but it doesn’t compare with the triple that diverted into the big island a few years ago on the way up from AKL to the west coast


They were on one engine for over three hours, not a comfortable feeling over the pacific

How has the figure gone from 45 minutes to 3 hours for this incident?



Two different incidents.
Much like a GE90, I'm a huge fan of Big Twins...
 
bhill
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 1:22 am

Curious, in a case like this, would it have been better to have the ability to lock the fan? Or would that be even worse from the drag? How many RPM's does the thing windmill at that airspeed?
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B737900ER
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 1:36 am

na wrote:

No way I´d fly on a Twin over the open Pacific.

Your options are extremely limited if that’s truly the case.
 
B737900ER
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 1:38 am

DocLightning wrote:

They could go hunting, after all they do know exactly where the A/C was when the failure occurred.

They can’t find an entire 777. There’s no way they would spot an engine cowl. That thing is gone. I doubt it would tell them any thing about the incident anyway.
 
rnav2dlrey
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 1:50 am

na wrote:
Max Q wrote:
They were on one engine for over three hours, not a comfortable feeling over the pacific


No way I´d fly on a Twin over the open Pacific. What a horror to depend on one engine on a old plane way past its prime for 3 hours.


please provide a list of tragedies caused by twins operating TPAC/hawaii flights since the introduction of ETOPS.
 
Max Q
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 2:17 am

Yes, you don’t have much choice these days and in a few years you’ll have no choice at all


Twins own the market now
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ssteve
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 2:27 am

B737900ER wrote:
na wrote:

No way I´d fly on a Twin over the open Pacific.

Your options are extremely limited if that’s truly the case.


Nah, just charter one of the last few DC-8s. That's safer than a twin, right?
 
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ikolkyo
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 3:32 am

na wrote:
Max Q wrote:
They were on one engine for over three hours, not a comfortable feeling over the pacific


No way I´d fly on a Twin over the open Pacific. What a horror to depend on one engine on a old plane way past its prime for 3 hours.


Gonna be pretty tough for you to get over there then, what a silly comment.
 
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Runway28L
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 3:37 am

Found some up-close photos of N773UA's engine:

http://www.instagram.com/p/BfM6XPzHp83/
Greetings from KPIT! Check out my photos here: http://www.airliners.net/search?user=45 ... teAccepted
 
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Jouhou
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 6:45 am

B737900ER wrote:
DocLightning wrote:

They could go hunting, after all they do know exactly where the A/C was when the failure occurred.

They can’t find an entire 777. There’s no way they would spot an engine cowl. That thing is gone. I doubt it would tell them any thing about the incident anyway.


Not to mention a piece of a cowling is one of the few pieces of that particular 777 found due to it being light enough for ocean currents to carry over long distances. It's probably not actually in the area of where it fell anymore.
 
Western727
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 1:14 pm

Friend of mine posted this video on his Facebook wall showing what seems to be a windmilling engine that's off balance as suspected by some of you on this thread: https://www.facebook.com/KITV4/videos/1 ... 054696861/
Jack @ AUS
 
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UAL747422
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 2:07 pm

tail number for this 777? wanting to see if I have flown on it.
I just love the 747, as you already may have noticed.
 
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iahcsr
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 2:15 pm

UAL747422 wrote:
tail number for this 777? wanting to see if I have flown on it.

N773UA, Ship 2473
Working Hard, Flying Right Friendly....
 
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UAL747422
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 2:29 pm

iahcsr wrote:
UAL747422 wrote:
tail number for this 777? wanting to see if I have flown on it.

N773UA, Ship 2473


That is one of the test 777 airplanes, with n777ua being the first production one. A family member of mine who flies for UA has flown that airplane. I'm seeing a similarity here, as NWA 85's accident was a 744 that was the 744 prototype and had been used for testing before it entered service. Did the same thing possibly happen on UA 1175?
I just love the 747, as you already may have noticed.
 
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ikolkyo
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 2:37 pm

UAL747422 wrote:
iahcsr wrote:
UAL747422 wrote:
tail number for this 777? wanting to see if I have flown on it.

N773UA, Ship 2473


That is one of the test 777 airplanes, with n777ua being the first production one. A family member of mine who flies for UA has flown that airplane. I'm seeing a similarity here, as NWA 85's accident was a 744 that was the 744 prototype and had been used for testing before it entered service. Did the same thing possibly happen on UA 1175?


What connection are you trying to make? Test aircraft are more prone to failures then regular? That’s simply false and I guarantee the engines on this aircraft are not the same from when it was a test aircraft.
 
B737900ER
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 4:22 pm

UAL747422 wrote:
iahcsr wrote:
UAL747422 wrote:
tail number for this 777? wanting to see if I have flown on it.

N773UA, Ship 2473


That is one of the test 777 airplanes, with n777ua being the first production one. A family member of mine who flies for UA has flown that airplane. I'm seeing a similarity here, as NWA 85's accident was a 744 that was the 744 prototype and had been used for testing before it entered service. Did the same thing possibly happen on UA 1175?

No, because that engine has been changed probably five to ten times over the life of that airframe. When you have engine related issues you have to separate airframe from engine because they are two completely separate components, each with a different life course.
 
gwrudolph
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 4:42 pm

UAL747422 wrote:
iahcsr wrote:
UAL747422 wrote:
tail number for this 777? wanting to see if I have flown on it.

N773UA, Ship 2473


That is one of the test 777 airplanes, with n777ua being the first production one. A family member of mine who flies for UA has flown that airplane. I'm seeing a similarity here, as NWA 85's accident was a 744 that was the 744 prototype and had been used for testing before it entered service. Did the same thing possibly happen on UA 1175?


BTW, a little off topic, but I'm not 100% sure N777UA was first production 777. It was, however, the first 777 placed into service.
 
United1
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 5:19 pm

gwrudolph wrote:
UAL747422 wrote:
iahcsr wrote:
N773UA, Ship 2473


That is one of the test 777 airplanes, with n777ua being the first production one. A family member of mine who flies for UA has flown that airplane. I'm seeing a similarity here, as NWA 85's accident was a 744 that was the 744 prototype and had been used for testing before it entered service. Did the same thing possibly happen on UA 1175?


BTW, a little off topic, but I'm not 100% sure N777UA was first production 777. It was, however, the first 777 placed into service.


It wasn't....the first 777 was used during the test program then re engined IIRC and sold to CX.
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Western727
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 7:06 pm

United1 wrote:
gwrudolph wrote:
UAL747422 wrote:

That is one of the test 777 airplanes, with n777ua being the first production one. A family member of mine who flies for UA has flown that airplane. I'm seeing a similarity here, as NWA 85's accident was a 744 that was the 744 prototype and had been used for testing before it entered service. Did the same thing possibly happen on UA 1175?


BTW, a little off topic, but I'm not 100% sure N777UA was first production 777. It was, however, the first 777 placed into service.


It wasn't....the first 777 was used during the test program then re engined IIRC and sold to CX.


I remember that vaguely, yes. If memory serves there was also a thread about it here discussing the nuances involved in re-engining a 777 from one engine mfr to another and why it's (generally) not cost-effective to do so (electrical/hyd/pneumatic connections, etc. being unique to an airframe built for a given engine mfr). 777 #1 being re-engined to CX was discussed as an exception given the unique history of the aircraft and CX being willing to acquire it on the cheap.
Jack @ AUS
 
DaufuskieGuy
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 11:03 pm

given the age of the plane, I'm wondering is this engine still in production? If not would they replace both engines with new versions?
 
muralir
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Re: United 1175 - Engine Cowling Fails

Thu Feb 15, 2018 11:52 pm

Max Q wrote:
They were on one engine for over three hours, not a comfortable feeling over the pacific


I'm curious how that could be. An ETOPS180 rating only allows you to be a max of 3 hours away from a diversion airport at any given time. Which means even if the engine failed at the worst possible moment, there *had* to have been an airport within 3 hours. Are you saying that they didn't immediately head to the nearest diversion airport? Not disputing your facts, I'm just curious what circumstances led to a plane flying on one engine for over 3 hours. My understanding is that should never happen for an ETOPS180-rated flight.
 
mabadia71
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Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 12:07 am

muralir wrote:
Max Q wrote:
They were on one engine for over three hours, not a comfortable feeling over the pacific


I'm curious how that could be. An ETOPS180 rating only allows you to be a max of 3 hours away from a diversion airport at any given time. Which means even if the engine failed at the worst possible moment, there *had* to have been an airport within 3 hours. Are you saying that they didn't immediately head to the nearest diversion airport? Not disputing your facts, I'm just curious what circumstances led to a plane flying on one engine for over 3 hours. My understanding is that should never happen for an ETOPS180-rated flight.


Not sure about which case specifically this was, or which aircraft, but, for instance, the 777 and the A333 are rated ETOPS330
mabadia71
 
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UAL747422
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Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 12:31 am

ikolkyo wrote:
UAL747422 wrote:
iahcsr wrote:
N773UA, Ship 2473


That is one of the test 777 airplanes, with n777ua being the first production one. A family member of mine who flies for UA has flown that airplane. I'm seeing a similarity here, as NWA 85's accident was a 744 that was the 744 prototype and had been used for testing before it entered service. Did the same thing possibly happen on UA 1175?


What connection are you trying to make? Test aircraft are more prone to failures then regular? That’s simply false and I guarantee the engines on this aircraft are not the same from when it was a test aircraft.


Somewhat that, but this is the second time that something has happened with a test airplane. My question being should airplanes that were used in a test program and then went into commercial service with an airline have heavier maintenance checks or stricter maintenance schedules etc.
I just love the 747, as you already may have noticed.
 
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Spacepope
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Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 12:40 am

UAL747422 wrote:
ikolkyo wrote:
UAL747422 wrote:

That is one of the test 777 airplanes, with n777ua being the first production one. A family member of mine who flies for UA has flown that airplane. I'm seeing a similarity here, as NWA 85's accident was a 744 that was the 744 prototype and had been used for testing before it entered service. Did the same thing possibly happen on UA 1175?


What connection are you trying to make? Test aircraft are more prone to failures then regular? That’s simply false and I guarantee the engines on this aircraft are not the same from when it was a test aircraft.


Somewhat that, but this is the second time that something has happened with a test airplane. My question being should airplanes that were used in a test program and then went into commercial service with an airline have heavier maintenance checks or stricter maintenance schedules etc.

No.
The system that failed here (likely engine, but perhaps cowling) are almost certainly not the parts the aircraft was delivered with, and therefore were not even part of the test program.
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ikolkyo
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Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 12:52 am

UAL747422 wrote:
ikolkyo wrote:
UAL747422 wrote:

That is one of the test 777 airplanes, with n777ua being the first production one. A family member of mine who flies for UA has flown that airplane. I'm seeing a similarity here, as NWA 85's accident was a 744 that was the 744 prototype and had been used for testing before it entered service. Did the same thing possibly happen on UA 1175?


What connection are you trying to make? Test aircraft are more prone to failures then regular? That’s simply false and I guarantee the engines on this aircraft are not the same from when it was a test aircraft.


Somewhat that, but this is the second time that something has happened with a test airplane. My question being should airplanes that were used in a test program and then went into commercial service with an airline have heavier maintenance checks or stricter maintenance schedules etc.


No. You’re trying to compare an unrelated incident from 16 years ago to this incident which involves a part that wasn’t even attached to this plane during testing.
 
benbeny
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Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 2:43 am

Could the blade get metal fatigue?
 
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GreenArc
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Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 3:24 am

muralir wrote:
Max Q wrote:
They were on one engine for over three hours, not a comfortable feeling over the pacific


I'm curious how that could be. An ETOPS180 rating only allows you to be a max of 3 hours away from a diversion airport at any given time. Which means even if the engine failed at the worst possible moment, there *had* to have been an airport within 3 hours. Are you saying that they didn't immediately head to the nearest diversion airport? Not disputing your facts, I'm just curious what circumstances led to a plane flying on one engine for over 3 hours. My understanding is that should never happen for an ETOPS180-rated flight.


The ETOPS 180 requirement you are referring to is a dispatch function. The flight must be planned to be within 180 minutes of a suitable airport. Once in the operation, the diversion can be flown to any airport the crew deems suitable at any airspeed the crew deems appropriate. There are many factors that can be legitimately considered in such a situation. Of course, all decisions must be adequately justified.

For example, the crew might elect to overfly their original designated alternate to one with a longer runway should the ability of the aircraft to be slowed and stopped be negatively impacted. Or the crew might elect to fly the diversion at a lower speed should there be airworthiness or fuel issues. ETOPS dispatch calculations usually involve a planned diversion at very high speed for greater route flexibility. Often times, such a speed is not appropriate to the emergency: Vibration caused by aerodynamic load, such as with structural failure, would be a good reason to divert at reduced speed thus yielding a longer divert time than originally flight planned.

So, in short, a 200 minute diversion after being dispatched ETOPS 180 may not be inappropriate or a violation of the terms of dispatch.
 
muralir
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Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 3:34 am

GreenArc wrote:
The ETOPS 180 requirement you are referring to is a dispatch function. The flight must be planned to be within 180 minutes of a suitable airport. Once in the operation, the diversion can be flown to any airport the crew deems suitable at any airspeed the crew deems appropriate. There are many factors that can be legitimately considered in such a situation. Of course, all decisions must be adequately justified.

For example, the crew might elect to overfly their original designated alternate to one with a longer runway should the ability of the aircraft to be slowed and stopped be negatively impacted. Or the crew might elect to fly the diversion at a lower speed should there be airworthiness or fuel issues. ETOPS dispatch calculations usually involve a planned diversion at very high speed for greater route flexibility. Often times, such a speed is not appropriate to the emergency: Vibration caused by aerodynamic load, such as with structural failure, would be a good reason to divert at reduced speed thus yielding a longer divert time than originally flight planned.

So, in short, a 200 minute diversion after being dispatched ETOPS 180 may not be inappropriate or a violation of the terms of dispatch.


Got it. Thanks for the explanation!
 
Max Q
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Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 5:36 am

muralir wrote:
Max Q wrote:
They were on one engine for over three hours, not a comfortable feeling over the pacific


I'm curious how that could be. An ETOPS180 rating only allows you to be a max of 3 hours away from a diversion airport at any given time. Which means even if the engine failed at the worst possible moment, there *had* to have been an airport within 3 hours. Are you saying that they didn't immediately head to the nearest diversion airport? Not disputing your facts, I'm just curious what circumstances led to a plane flying on one engine for over 3 hours. My understanding is that should never happen for an ETOPS180-rated flight.




If you google ‘longest one engine diversion’
it will give you all the details on the flight
I’m referring to
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deltal1011man
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Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 8:54 am

DaufuskieGuy wrote:
given the age of the plane, I'm wondering is this engine still in production? If not would they replace both engines with new versions?

UA has spare engines but yes, Pratt is still making the PW4000s.
 
na
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Joined: Sun Dec 12, 1999 3:52 am

Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 1:31 pm

ssteve wrote:
B737900ER wrote:
na wrote:

No way I´d fly on a Twin over the open Pacific.

Your options are extremely limited if that’s truly the case.


Nah, just charter one of the last few DC-8s. That's safer than a twin, right?


Silly comment when there are hundreds of A380s, 748s and A340s around.

ikolkyo wrote:
na wrote:
Max Q wrote:
They were on one engine for over three hours, not a comfortable feeling over the pacific


No way I´d fly on a Twin over the open Pacific. What a horror to depend on one engine on a old plane way past its prime for 3 hours.


Gonna be pretty tough for you to get over there then, what a silly comment.


So you are perfectly fine if an engine fails over the middle of the Pacific? Tough guy! Remember Titanic, and Murphys law.
 
na
Posts: 9568
Joined: Sun Dec 12, 1999 3:52 am

Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 1:31 pm

deltal1011man wrote:
DaufuskieGuy wrote:
given the age of the plane, I'm wondering is this engine still in production? If not would they replace both engines with new versions?

UA has spare engines but yes, Pratt is still making the PW4000s.


PW is currently scrapping a number of Vietnam 77Es for their engines.
 
DaufuskieGuy
Posts: 396
Joined: Tue Sep 23, 2008 6:35 pm

Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 5:02 pm

deltal1011man wrote:
DaufuskieGuy wrote:
given the age of the plane, I'm wondering is this engine still in production? If not would they replace both engines with new versions?

UA has spare engines but yes, Pratt is still making the PW4000s.


ah OK. And like with the Swiss 77W, they'll have to ferry a new one with an Anotov?
 
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Spacepope
Posts: 3798
Joined: Tue Dec 28, 1999 11:10 am

Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 5:09 pm

DaufuskieGuy wrote:
deltal1011man wrote:
DaufuskieGuy wrote:
given the age of the plane, I'm wondering is this engine still in production? If not would they replace both engines with new versions?

UA has spare engines but yes, Pratt is still making the PW4000s.


ah OK. And like with the Swiss 77W, they'll have to ferry a new one with an Anotov?

The core and fan can be split, so it can be done with smaller freighters.

Would love to have seen Boeing do a "Third pod" for engine ferries on the 777 though.
The last of the famous international playboys
 
benbeny
Posts: 202
Joined: Thu Nov 03, 2016 1:44 pm

Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 6:18 pm

Spacepope wrote:
DaufuskieGuy wrote:
deltal1011man wrote:
UA has spare engines but yes, Pratt is still making the PW4000s.


ah OK. And like with the Swiss 77W, they'll have to ferry a new one with an Anotov?

The core and fan can be split, so it can be done with smaller freighters.

Would love to have seen Boeing do a "Third pod" for engine ferries on the 777 though.

No way they're gonna do that. Just imagine what will happen when the engine fails at V1 on the same side with the pod. The drag would be enormous from 2 inop engines on the same wing.

Besides IIRC GE90 can be taken apart and shipped on 777F or 747F, which are plenty out there.
 
B737900ER
Posts: 917
Joined: Thu Aug 31, 2006 10:26 am

Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 6:28 pm

na wrote:

Silly comment when there are hundreds of A380s, 748s and A340s around.


And how many of those are crossing the pacific each day?
Maybe 3. Twin engine is the standard. It’s not 1988 anymore.
 
Passedv1
Posts: 570
Joined: Sun Oct 07, 2012 3:40 am

Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 10:22 pm

Under Part 121, a US carrier or an airplane flying in US airspace is required to divert to the “nearest suitable airport in point of time.”

I would guess that in this case OGG was the nearest airport, however, the Captain could determine OGG to not be “suitable” and press on to HNL.

I have seen a closeup picture of the N1 fan. One of the blades is clearly broken off with only a 3ish inch stub left in the leading edge connection of the blade. It did not disconnect or fracture at the hub, the blade clearly fractured. The blade immediately next in rotation is fractured about 60% up the length. As was stated earlier, 3 or 4 bypass stators were missing at about the 7-8 o’clock position. Almost all of the N1 blades have some sort of damage ranging from extensive tip damage with several of the blades having mid-span damage.

Is it even possible for a soft cowling “aluminum or composite” to do that kind of damage to an N1 blade? It seems likely to me that the blade fracture came first.
 
UA444
Posts: 2700
Joined: Sun Mar 09, 2014 7:03 am

Re: United 1175 - Engine Cowling Fails

Fri Feb 16, 2018 10:38 pm

na wrote:
deltal1011man wrote:
DaufuskieGuy wrote:
given the age of the plane, I'm wondering is this engine still in production? If not would they replace both engines with new versions?

UA has spare engines but yes, Pratt is still making the PW4000s.


PW is currently scrapping a number of Vietnam 77Es for their engines.

That doesn’t mean they aren’t still making them. They probably want them to resell for themselves.
 
weekendppl
Posts: 92
Joined: Tue Sep 01, 2015 5:59 am

Re: United 1175 - Engine Cowling Fails

Sat Feb 17, 2018 7:15 am

na wrote:
No way I´d fly on a Twin over the open Pacific. What a horror to depend on one engine on a old plane way past its prime for 3 hours.

Then the *only* way you'll get from the mainland US to Hawaii is by shipping yourself and hoping you get manifested on a UPS or Kalita 747 or UPS or FedEx MD-11. Every passenger flight from Mainland US to Hawaii is a twin these days.
 
friendlyskies22
Posts: 45
Joined: Wed Jan 13, 2016 4:58 pm

Re: United 1175 - Engine Cowling Fails

Mon Feb 19, 2018 3:28 am

any word on dispo of N773UA? Engine change at HNL? Obviously needs some cowling work as well.
New engine arrived yet? Any other structural damage found?
Keep 'er flying!
 
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VirginFlyer
Posts: 4976
Joined: Sun Sep 10, 2000 12:27 pm

Re: United 1175 - Engine Cowling Fails

Mon Feb 19, 2018 3:34 am

na wrote:
ssteve wrote:
B737900ER wrote:
Your options are extremely limited if that’s truly the case.


Nah, just charter one of the last few DC-8s. That's safer than a twin, right?


Silly comment when there are hundreds of A380s, 748s and A340s around.

ikolkyo wrote:
na wrote:

No way I´d fly on a Twin over the open Pacific. What a horror to depend on one engine on a old plane way past its prime for 3 hours.


Gonna be pretty tough for you to get over there then, what a silly comment.


So you are perfectly fine if an engine fails over the middle of the Pacific? Tough guy! Remember Titanic, and Murphys law.

Question for you: in the history of commercial jet aviation, how many instances have there been of multiple independent engine failures (as opposed to multiple engine failures caused by a common cause such as fuel exhaustion or debris ingestion)?

V/F
It is not for him to pride himself who loveth his own country, but rather for him who loveth the whole world. The earth is but one country, and mankind its citizens. —Bahá'u'lláh
 
Apprentice
Posts: 610
Joined: Sat Jan 19, 2013 12:51 pm

Re: United 1175 - Engine Cowling Fails

Mon Feb 19, 2018 9:19 am

RickNRoll wrote:
At least they make pylons better than they make cowlings.


Hi: Waiting an Inform detailing accident initial cause, but as it was pointed several times, nowadays cowlings need attention during mechani’s and pilot’ walk around.
My bet is a latch or several no closed properly, the rest - normal engine vibration in flight. I may be wrong, of course, it’s just a bet, waiting for final inform.
Difficult to find a yong mech who had received OJT about cowls clossing, including use of specially designed tool (no mandatory) and the order to close the locks..
At the same time, it’s very difficult to find a crew member wasting time, during walk arounds, checking properly latches positon.

And agree, Boeing and Airbus can desig a Closing cowl system with all the whistlles and lights, only to add 10 kg for each engine, and them receive critics about heavy cowlings!!

Rgds
“An AME, with just a Mechanic Role”, as per one of our pilots
"A NO" is a positive answer., "DON'T KNOW" is not. My Tutor (a wise man)
“CUBANA” 90 years Flying”
 
Apprentice
Posts: 610
Joined: Sat Jan 19, 2013 12:51 pm

Re: United 1175 - Engine Cowling Fails

Mon Feb 19, 2018 9:23 am

Hello. Sorry for my english in the above post. After 4 night’shifts, trying to recover my concentration.

Again sorry

Rgds
“An AME, with just a Mechanic Role”, as per one of our pilots
"A NO" is a positive answer., "DON'T KNOW" is not. My Tutor (a wise man)
“CUBANA” 90 years Flying”

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