UAL 328 Blows engine and returns to KDEN enroute to PHNL

[troyboy66 66]

https://www.ifn.news/posts/united-airlines-flight-ua328-suffers-serious-engine-failure/

https://flightaware.com/live/flight/UAL328/history/20210220/1925Z/KDEN/KDEN

[Chock 17,769]

Holy smokes that footage from the cabin looks alarming.

I had to laugh at the reporting language though on that link:

'A United Airlines Boeing 777 has suffered a serious engine failure shortly after departure...'

Aaah, one of those serious engine failures, as opposed to the nonchalant and comedy engine failures you can just ignore or laugh off.

[Ian S 214]

41 minutes ago, Chock said:

Holy smokes that footage from the cabin looks alarming.

I had to laugh at the reporting language though on that link:

'A United Airlines Boeing 777 has suffered a serious engine failure shortly after departure...'

Aaah, one of those serious engine failures, as opposed to the nonchalant and comedy engine failures you can just ignore or laugh off.

Yes, of course we need to be told it is serious as the majority or engine failures shortly after departure are usually trivial affairs not worth worrying about 😄 

[bugbee 26]

A big bang after the squeeze, not good. I'm happy they landed ok.

[HighBypass 2,339]

Nice bit of video footage in that first article. Distinct lack of of an engine nacelle/casing.

We all like to speculate - I presume the engine was just windmilling due to the airspeed? Not sure about the fire though.. Hopefully it was residual and extinguished itself??

It'll be an interesting report.

[Chock 17,769]

Judging by the way the engine is vibrating and the fact that pretty much all of cowling is gone, it looks very much like a front fan blade has let go and smashed through the ballistic shielding on the cowling, probably owing to the high engine RPM on the climb. I bet that went with a hell of a bang, and it may possibly have damaged the wing, rear fuselage or tailplane as the debris fell away.

Of course a  problem then is that with a fan blade gone, the engine is running with a seriously out of balance component spinning at several thousand RPM, which means other blades will more easily let go too, especially if shrapnel has hit them, creating further shrapnel which can go into the engine potentially damaging the fuel and lubrication systems, which is probably what those flames are about, although it could also be residue pooling in the bottom of the engine casing and burning off fairly harmlessly.

It'll be interesting to see if it was a maintenance issue, a component quality issue, or some kind of ingestion impact such as a bird strike; especially given the amount of downtime aeroplanes have had in recent months which might potentially have impacted on serviceability. It's something I daresay will be looked at very carefully given that a similar incident appears to have occurred on a 747 too on the same day, particularly since these two aeroplanes may potentially have engines which share some common components - possibly two versions of the PW4000 - although the Triple Seven and the Jumbo don't use the exact same variants of that engine, but it'll be intriguing if that is the case.

[UAL744 17]

On 2/20/2021 at 7:35 PM, Chock said:

Judging by the way the engine is vibrating and the fact that pretty much all of cowling is gone, it looks very much like a front fan blade has let go and smashed through the ballistic shielding on the cowling, probably owing to the high engine RPM on the climb. I bet that went with a hell of a bang, and it may possibly have damaged the wing, rear fuselage or tailplane as the debris fell away.

Of course a  problem then is that with a fan blade gone, the engine is running with a seriously out of balance component spinning at several thousand RPM, which means other blades will more easily let go too, especially if shrapnel has hit them, creating further shrapnel which can go into the engine potentially damaging the fuel and lubrication systems, which is probably what those flames are about, although it could also be residue pooling in the bottom of the engine casing and burning off fairly harmlessly.

It'll be interesting to see if it was a maintenance issue, a component quality issue, or some kind of ingestion impact such as a bird strike; especially given the amount of downtime aeroplanes have had in recent months which might potentially have impacted on serviceability. It's something I daresay will be looked at very carefully given that a similar incident appears to have occurred on a 747 too on the same day, particularly since these two aeroplanes may potentially have engines which share some common components - possibly two versions of the PW4000 - although the Triple Seven and the Jumbo don't use the exact same variants of that engine, but it'll be intriguing if that is the case.

I’ve been following this since news broke last weekend, and it appears not one but TWO blades broke, one in half and one near the base. The PW powered 747-400 use the PW4000-94 inch model and the PW powered 777 use the PW4000-112 inch model, and according to a documentary by CBS from 1990 on the 777 United uses the PW4084 and or the PW4077 on their PW powered 777s. But additional pictures released and shown in Colorado news stations reveal there was a significantly sized hole by the underside of the right wing root. Unless no additional photos are released, it can be feasibly assumed no other damage was done to the aircraft.

And after extensive viewing of the available videos it appears the engine was still running and still provided thrust and drove the engine driven generator and engine driven hydraulic pump(s). But the footage shows a continuous suppressed fire by the engine reverser sleeve with white smoke trailing it.

And the good news is the process of finding out what happened will be much easier owing to the fact that both blades and all the missing pieces from the cowling were recovered. And after recent announcements, numerous PW powered 777s with All Nippon Airways, Japan Airlines and United Airlines have been pulled from service for emergency engine inspections with Korean Airlines and Asiana Airlines following suit just this morning.