According to the Seattle Times there are now 36 aircraft grounded out of 686 tested. A repair station is now being set up in Victorville.
If the pickle fork is really affected on every single 737NG then this is a problem for Boeing because the pickle fork should last for the whole life time of the aircraft. I guess the repair costs and the compensation for the 3 weeks of grounding will probably be paid for by Boeing (product liability). As the NG is at the end of its production cycle, every single NG could be and probably will be over time affected. Thats over 6700 repairs over the next 10-20 years, which would be 1-2 aircraft per day, with a duration of 21 days for the repair, thats between 20-40 aircraft affected at the same time. So lets hope it is an isolated case only affecting a limited amount of pickle forks due to a bad delivery and not a construction fault effecting all of them.
Here is the source: https://www.seattletimes.com/business/boeing-aerospace/cracks-found-on-more-than-5-of-older-boeing-737s-in-pickle-fork-inspections/
The 21 day repair is to replace the pickle forks with new ones. As lightsaber said, a reinforcement modification will be developed and installed on all aircraft BEFORE the cracks develop. This modification will certainly be far less expensive and time consuming. As lightsaber also said, once a repair is certified, a repair and reinforcement will be able to be done on aircraft with cracks that doesn't involve replacing the pickle forks with new ones. This will also be a less costly and time consuming repair.
They aren't just going to inspect and replace pickle forks when cracks are found for the rest of the 737NG service life.
Alright, that's good news.
Does anyone here has a rough estimation what a fix like this would cost? The development, testing and certification will probably cost a bit. Afterwards when it can be done on premise from the airline maintenance it should be rather cheap, a few hours of work.
The pickle fork replacement is a 3 week job, almost certainly two shifts. Probably 15 ish people on overtime, so about 2,250 hours. Parts, management and such brings a pickle fork replacement to just under a million USD plus the equivalent lease cost.
The Permanent repair will be a 3 shift job at most, so 120 labor hours (including QA, parts crin and such). So maybe $100,000, much less at low wage MRO shops.
The temporary repair will be maybe 20 hours or less. So maybe $10,000. But this only allows flying for some limited time.
There is a reason the system is set up as it is.
For example, the first Embraer wing spar repairs were an equally huge deal. Equivalent scariness and cost. Eventually the root cause was found and only 62 aircraft were impacted: (warning, pdf):http://services.casa.gov.au/airworth/ai ... 90-017.pdf
All the above are guesses, obviously.
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