Regulators probe engine blow-outs as older Boeing 777s suspended

[turbinetree]

Last edited Mon Feb 22, 2021, 03:57 PM - Edit history (1)

Source: Reuters

AEROSPACE AND DEFENSE
FEBRUARY 21, 2021 6:27 PM UPDATED 43 MINUTES AGO

By Jamie Freed, David Shepardson, Laurence Frost 4 MIN READ

(Reuters) - Showers of jet engine parts over residential areas on both sides of the Atlantic have caught regulators’ attention and prompted the suspension of some older Boeing planes from service.

The Saturday incidents involving a United Airlines 777 in Denver and a Longtail Aviation 747 cargo plane in the Netherlands have put engine maker Pratt & Whitney in the spotlight - although there is as yet no indication that their causes are related.

Raytheon-owned Pratt & Whitney said it was coordinating with regulators to review inspection protocols.

Reporting by Jamie Freed in Sydney, David Shepardson in Washington and Laurence Frost in Paris; additional reporting by Eimi Yamamitsu and Maki Shiraki in Tokyo, Joyce Lee in Seoul, Tim Hepher in Paris and Anthony Deutsch in Amsterdam; Editing by Sam Holmes, Christopher Cushing and Emelia Sithole-Matarise




Read more: https://www.reuters.com/article/us-boeing-777-japan/regulators-probe-engine-blow-outs-as-older-boeing-777s-suspended-idUSKBN2AL0PD

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The determining factor on this engine as well as others is the "cycles" of take-off and landing it had and when it had a complete tear down and inspection on the parts

[DeminPennswoods]

1. Fan blade failure

At least one fan blade was broken off at mid-span on the Delta Den-Honolulu flight 777 engine.

And when did United Technologies sell Pratt?

[paleotn]

6. Haven't. Still part of UTC...actually RTC with the Raytheon merger.

I have colleagues at Pratt. Figured it was a GE90 that crapped out. Nope. Older Pratt engine. Crap.

[DeminPennswoods]

7. Ok, thanks

Been away from DoD for awhile now and haven't kept up with the industry. Am familiar with rotating parts like blades, disks failing.

[bucolic_frolic]

2. Metal fatigue

Vibration, stresses, extremes of temperature up and down. Every so often a plane from WWII crashes. There is a life cycle to machinery. Problem is determining the limits, inspection criteria and methods, schedule, and money.

[DeminPennswoods]

8. The engine is hot and spins at tremendous speed

Even the best engineered and manufactured parts can fail under that kind of stress. But there are also occassional problems with microscopic impurities in the castings and forgings from which blades are made. It doesn't take much for that to evolve into a failure that could be isolated and specific.

Money is the biggest driver. It's expensive to pull an engine, inspect and replace blades or vanes or disks. The blades come in matched, balanced sets. You can't just replace 1 blade, you have to replace both lest you put the fan or compressor stage out of balance.

[RussBLib]

3. talk about aging infrastructure

it's everywhere, even falling out of the sky!

[Joe Nation]

4. Has anyone talked about a bird or a drone strike being responsible for the engine failure?

Curious because they were still at a low altitude when the failure happened.

[regnaD kciN]

5. Some people at Airliners.net were speculating on that possibility early on...

...but apparently some information that has come out since then has made them decide that probably wasn't the cause.

[Joe Nation]

11. Thanks

[James48]

9. Lost two blades.

Design regs are that it should not have lost two blades, and it should not have become an uncontainable failure- meaning parts fell to the ground. Design criteria regulations are such that it isn’t supposed to happen.

That particular engine model is 30+ years old, and a high time engine is support to get lots of inspections to prevent just such a possible failure of fan blades-

Obviously that is going to have to be re-examined, and new inspection criteria developed.

[turbinetree]

10. Yepper spot on................

When they do line checks inspections on those fan blades during a fan blade lube they perform that blade inspection eddy current and dye penetrant inspection of those blades, most people do not know that the blades are balanced across from each other in pairs and at all the times they are numbered so that you don't have the blades being placed willy nilly back on the fan blade tree hub since there are 18 blades on that hub disk