United plane's fan blade had multiple cracks; last inspected 4 years ago: NTSB

Fox News ^ | 3-6-21 | Brie Stimson

[ScubaDiver]

I hope not if for no other reason than they’re supposed to be titanium.

[EEGator]

Did you see the creepy murals in the airport?

[JohnBrowdie]

I understand what happened, and I understand that you’re trying to be clever.

it was an engine problem. design, manufacture, or maintenance; perhaps even a combination of some or all of those — still an engine problem.

[Wuli]

“The broken blade on the Pratt & Whitney engine had been used on 2,979 flights since its last inspection in 2016, the NTSB said. It wasn’t due for another inspection until it reached 6,500 flights – more than twice the number it had flown when it broke.”

Conclusion/Questions:.

1. The blade in question obviously shows conditions the inspection standard did not expect to see after 2,979 flights. Is the standard wrong; should all such blades be inspected sooner than the current standard of after 6,500 flights.

2. Is there something materially wrong - defective - with the blade that failed; and how did the defect enter the manufacturing process, singularly, or with other blades that need or be identified and inspected.

3. Some process needs to be conducted to determine where the material fault lies; with the first question - the inspection standard, or the second - material defect that somehow arose in the manufacture of the blade.

[McGruff]

...engine had been used on 2,979 flights since its last inspection in 2016, the NTSB said. It wasn’t due for another inspection until it reached 6,500 flights...

Not comforting statistics. And United supposed to be one of the better airlines.

[linMcHlp]

The weather conditions, travel problems, and then, when I finally found a place to set down, and looked out the window, there was the first Boeing 777 I had ever seen - and it was in trouble.

That is what I remember.

[EVO X]

Here is a hour long interview with the captain of United 1175 that had a similar malfunction 200 miles from Honolulu in 2018. He had to fight the airplane all the way into Honolulu. If they would have been farther out, it is likely they wouldn’t have made it.

Capt. Behnam UAL#1175​ Fan Blade Out Event INTERVIEW

https://www.youtube.com/watch?v=J7_lzeY23dI

[charleywhiskey]

Not so. I was there when the ultimate stress test was done on the 777 wing (in Seattle) and was in the next building when it finally broke - way beyond the design limits. There was a lot of cheering for this excellent result.

[FreedomPoster]

Most are. Not so much hollow as internal cooling passages. Been that way for a long, long time.

[EVO X]

Animation of the United Honolulu incident. The pilots comments and animation start about 5 minutes in.

https://www.youtube.com/watch?v=NDLqxaSwPYM

[FreedomPoster]

This man failure analyzes!

[FreedomPoster]

But this was a fan blade, not a turbine blade? Different issue.

[GBA]

It could have easily been damaged while in service.

Those big turbofans are basically huge kerosene powered vacuum cleaners sucking in all sorts of potentially damaging things like rocks, ice, birds, small animals, young children, loose baggage and slow baggage handlers, bikes, scooters, SmartCars, etc.

I’m amazed by how reliable and trouble-free jet engines are today.

[mad_as_he$$]

They are not made of steel. A very complicated process.

https://www.youtube.com/watch?v=vN3_Wkyl5PQ

[BwanaNdege]

Inspections should have been done based upon flight hours. Inspection costs suffered with cost cuts because of the impact of the pandemic.

Depending on which part of the aircraft is being inspected, flight cycles, i.e. Takeoffs & Landings, Engine Starts, etc have as much effect as total hours.

Climbing to altitude changes the pressure differential inside/outside on the fuselage, steady flight at altitude does not. Engine starts and power changes cause more thermal stress than steady-state operation as on a long flight.

The list goes on...

Also, inspections are MANDATED and not subject to your financial/accounting problems.

[JohnBrowdie]

don’t try to resort to common sense in this thread. we’ve already gone flight 800, and boeing is run by international criminals.

we won’t be assimilated.

[linMcHlp]

bttt

[linMcHlp]

Noise, vibration, and harshness. (”NVH”)

Individual objects may possess any combination.

Assemblies, too.

The engine itself an assembly, is also part of a larger assembly.

NVH traveling thru some assembly/structure(s).

Various parts may have cracks, that do not suffer, while other parts may have cracks that do suffer.

A vibration 40 ft away may not agitate some part, but 31.23976 ft away, does agitate the same part.

IOW, aging can be affected.

[hecticskeptic]

Depending on which part of the aircraft is being inspected, flight cycles, i.e. Takeoffs & Landings, Engine Starts, etc have as much effect as total hours.
~~~~~~~~~~~~~~~~~~~~~

Agreed and no doubt there will be some components for which both the flight cycles and total hours are used to establish maintenance schedules.

By the way, I just took a look at your profile page... God bless you and your wife for what you do.

[minnesota_bound]

Comment at article:
Fleecewater: Maybe P&W went to using Chinesium fan blades to cut costs.

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Could be as the bridge in San Francisco was using Chinesium steel for the Bay Bridge and this has cost many 10’s of millions in repairs and legal bills.

Google: bay bridge using chinese steel
https://www.americanmanufacturing.org/blog/dang-the-chinese-made-bay-bridge-continues-to-fall-apart/