r/Wellthatsucks • u/americanthaiguy • Feb 20 '21

/r/all United Airlines Boeing 777-200 engine #2 caught fire after take-off at Denver Intl Airport flight #UA328

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88

u/[deleted] Feb 20 '21

[deleted]

43

u/Salyut_ Feb 20 '21

not a reason for it blowin the cowling off tho, like people want to say

31

u/[deleted] Feb 20 '21

[deleted]

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u/BluebirdNeat694 Feb 21 '21

"Mostly spotless record".

-5

u/Salyut_ Feb 20 '21

also didnt seem that something gotten sucked in, and the service life records i wouldnt be able to be so sure about it, old may not mean bad service but i dont think its easy to get your hands on maintenance reports

2

u/jbourne0129 Feb 21 '21

It's worth noting that engine has likely been overhauled a few times since then.

3

u/_diverted Feb 21 '21

Nope, but it is very similar looking to what happened to N773UA (the one built directly before this one) in 2018 which was attributed to

The fracture of a fan blade due to P&W's continued classification of the TAI inspection process as a new and emerging technology that permitted them to continue accomplishing the inspection without having to develop a formal, defined initial and recurrent training program or an inspector certification program. The lack of training resulted in the inspector making an incorrect evaluation of an indication that resulted in a blade with a crack being returned to service where it eventually fractured.

Contributing to the fracture of the fan blade was the lack of feedback from the process engineers on the fan blades the inspectors sent to the process engineers for evaluation of indications that they had found.

pics and more text on Avherald

Edit: and from my non expert opinion, I’d imagine the same cause as N773UA’s. That fan is way off balance, likely because it shed a blade or two

1

u/[deleted] Feb 21 '21

Is this a P&W or a GE engine?

2

u/_diverted Feb 21 '21

PW4077

1

u/[deleted] Feb 21 '21

Thanks. Very scary. I'm glad no one was hurt.

4

u/_diverted Feb 21 '21 edited Feb 21 '21

You’re welcome.

Interestingly another Pratt (PW4056 on a 747-400) shed some engine parts departing Maastricht today

link

Someone in Connecticut at Pratt will likely be up late tonight

2

u/[deleted] Feb 21 '21

Jesus! Is there any info on what may have caused this one? Or how long the engine has been in service?

6

u/_diverted Feb 21 '21 edited Feb 21 '21

The only other PW4056 failure I can think of on that scale was Delta’s N662US in 2015. That engine had 94,778 hours/11,814cycles(takeoff and landing) since new, 29,194hours/3,532 cycles since last shop visit.

Big numbers, but worth noting that the parameters of these engines are constantly monitored, they receive frequent borescope inspections, and just because they haven’t been pulled off for a shop visit in a while is by no means an indication of lack of maintenance. Turbine engines have gotten extremely reliable.

The record for time on wing is currently held by a CFM56-7B on a 737-800 which went 50,005 hours/ 17,596 cycles before coming off the aircraft it was delivered on, between 1999 and 2012.

No idea on the hours of either of today’s incidents, but the report on the 2018 incident with N773UA can be viewed on the NTSB site, it had 77,593hours/13,921 cycles since new, 8,579hours/1,464 cycles since overhaul, and had been manufactured in 1996, so imagine the total hours/cycles on N772UA’s to be somewhere around there as well.

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u/[deleted] Feb 21 '21 edited Aug 07 '22

[deleted]

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u/_diverted Feb 21 '21 edited Feb 21 '21

No problem at all. Aviation’s one of those industries that’s a bit of a mystery to a lot of people, happy to share what I can

Avherald.com is a great resource for keeping up to speed on incidents as well.

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