777/PW4000 Fleet Grounded by FAA

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120 777-200s and 300s with the PW4000 grounded by FAA after Saturday's uncontained failure over Denver. Japan followed suit and South Korea says it's watching the situation.

Boeing can't seem to catch a break at the moment.

 
Turns out there were two PW4000 uncontained failures on Saturday, the second on a 747 in the Netherlands during climb out of Maastricht, with someone on the ground hit by a fragment (the 777 article has been amended to cover it as well). With the Japanese incident in December - I haven't seen it explicitly called an uncontained failure but the damage looks consistent with one - that makes three in three months.

 
Could well be, unfortunately. Then again, plenty of fake aviation parts still flooding the market...
 
"Initial examination of the Denver 777 engine showed that two fan blades had fractured, accorded to the US National Transportation Safety Board"

Just to deal with the speculation, fan blades will only get into the secondary market if they're from a stripped engine, and they're too complex to fake - investment castings, complex shapes, rare alloys. Has anyone even parted out a 777-200 or 300 with PW4000-112s yet? On top of which both JAL and United are going to be thoroughly embedded with their own supply chains back to Boeing.

PW4000-94s are more likely to have parts available second-hand, and small charter carriers are more likely to access the second hand market. But looking at the debris this seems to be a full blade-off incident, not some minor damage from stator blades or similar working loose.

Article in Dutch with film of the debris from the Maastricht incident . I don't have more than the odd word of Dutch, but it definitely seems to say two injured not one The blade sticking out of the car roof is impressively scary - and seems to have a clear fracture surface at the top.

 
Article in Dutch with film of the debris from the Maastricht incident . I don't have more than the odd word of Dutch, but it definitely seems to say two injured not one The blade sticking out of the car roof is impressively scary - and seems to have a clear fracture surface at the top.


From what I've read elsewhere, the two injuries in the Netherlands were one woman in her 70s hit by a piece of debris and one man burned by a piece of hot metal when they went to pick it up. Neither seem to have been very serious injuries. Very lucky that that bit of blade hit a car instead of the top of someone's head.
 
Faulty training syllabus in engine's blades non destructive analysis identified as one factor in UA328 777 uncontained engine failure:

 

I still think Boeing asking for exemptions from safety rules is a bad move WRT the company's overall reputation (and the need to fix it), even if technically justified.
 
How difficult would it be for operators to swap to GE or RR engines? It would put a bunch of aircraft back in the air while making PW look bad at GE and RR's benefit. Seems like engine pods & their associated pylons would be pretty easily swappable and modularized for faster engine changes.
 
How difficult would it be for operators to swap to GE or RR engines? It would put a bunch of aircraft back in the air while making PW look bad at GE and RR's benefit. Seems like engine pods & their associated pylons would be pretty easily swappable and modularized for faster engine changes.
I was just reading something noting that 787 was the first aircraft on which that's true.

And even if it were possible on 777 you would need to source the engines, and find $40m+ per aircraft to pay for them.
 
I thought there were some engine leasing plans that existed ("power by the hour?"). Seems less a money issue and more a supply issue. Not making revenue is the real cost of the airline. Surely there is a ready supply of spares for any particular aircraft to get an appreciable number back in the air.....

Overproduction is of course something to avoid too, but in the time it takes PW to get back certifications, GE and RR could ramp up production to get leased in on a good number of originally PW powered airframes. PW aircraft, once recertified, can get refitted with their original engines and the leased out competitor powerplants can be returned to their respective manufacturers. They could be kept as spare for-lease engines or resold at a discount based on flight hours.
 
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I thought there were some engine leasing plans that existed ("power by the hour?"). Seems less a money issue and more a supply issue. Not making revenue is the real cost of the airline. Surely there is a ready supply of spares for any particular aircraft to get an appreciable number back in the air.....

Overproduction is of course something to avoid too, but in the time it takes PW to get back certifications, GE and RR could ramp up production to get leased in on a good number of originally PW powered airframes. PW aircraft, once recertified, can get refitted with their original engines and the leased out competitor powerplants can be returned to their respective manufacturers. They could be kept as spare for-lease engines or resold at a discount based on flight hours.

Power by the hour is mostly in relation to outsourced maintenance plans, IIRC. The capital cost of engines, at 10s of millions of dollars each, means that they're ordered specifically for going on a specific plane, with small numbers of spares held by the big fleets and the big external maintenance providers. You aren't going to be able to source anything like 120 pairs of engines from that (especially as the people who have them need them to cover maintenance issues with their own fleets).

And as it's not a simple switch - it's definitely a new pylon, possibly new wiring runs and a new FADEC, perhaps new cockpit software - there's no desire to try it. It would be interesting to see how the FAA etc would react, they might insist on an STC, given the degree of change, even if it is ending up as an established and certified configuration.

WRT the engine manufacturers, they have supply chains set up with long-lead items for the number of engines they're expecting to produce, and they're working flat out to meet the existing demands on them. Given neither they nor the operators knew how long the grounding was going to last, there was never a business case to try to ramp up production.
 
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