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Not excusing anything about MCAS, but the "cracks in an aluminum airframe" thing is a VERY normal and established cycle/process. Cracks can be a normal and ex

Not excusing anything about MCAS, but the "cracks in an aluminum airframe" thing is a VERY normal and established cycle/process. Cracks can be a normal and expected thing. These parts were designed to last the lifetime of the airframe (around 90,000 cycles) and are failing in under 30,000 cycles. This raises eyebrows for two specific reasons: 1.) Boeing was already installing subpar parts (edit: not pickle forks) from Ducommon in the 737 NG 2.) The wings fall off if the pickle forks fail completely. This news piece is just journalistic piling on to hot news. MCAS isn't the only fire Boeing is fighting right now (they're also battling poor quality control with their KC-46 and 787 lines among other things). Some guy on PPRuNe is claiming that the pickle fork problem was just improper manufacturing[1], which when put in context would make it appear as if Boeing has some major structural problems with its organization. 1: https://www.pprune.org/showpost.php?p=10595986&postcount=258 https://www.pprune.org/showpost.php?p=10595986&postcount=258

chopin 7y ago
> These parts were designed to last the lifetime of the airframe Can these be replaced? If they have the expected lifetime of the airframe they might not be serviceable. Out of curiosity: can these cracks be repaired other than replacing the part?
- msbarnett 7y ago
  > Can these be replaced? Yes. The operation takes a couple of days per plane.
throwaway5752 7y ago
Yes, but it's very long cycle failures at low frequency, and people suspect it's because of additional stress caused by winglets. Winglets reduce drag and save fuel, it's an important change. It may have been very difficult to predict and test this failure. And most importantly, the FAA and Boeing are handling it properly.
- inferiorhuman 7y ago
  Yes, but it's very long cycle failures at low frequency, and people suspect it's because of additional stress caused by winglets. Winglets reduce drag and save fuel, it's an important change. It may have been very difficult to predict and test this failure. And most importantly, the FAA and Boeing are handling it properly. Cracks have been found in NGs both with and without winglets, so that is almost certainly not the issue at hand.
notfromhere 7y ago
That's because when they merged with McDonnell Douglas, MD executives got the top spots in Boeing, so their shitty culture transferred over to the new company. The long-standing joke is that MD took over Boeing with Boeing's money

chopin 7y ago

> These parts were designed to last the lifetime of the airframe Can these be replaced? If they have the expected lifetime of the airframe they might not be serviceable. Out of curiosity: can these cracks be repaired other than replacing the part?

msbarnett 7y ago
> Can these be replaced? Yes. The operation takes a couple of days per plane.

throwaway5752 7y ago

Yes, but it's very long cycle failures at low frequency, and people suspect it's because of additional stress caused by winglets. Winglets reduce drag and save fuel, it's an important change. It may have been very difficult to predict and test this failure. And most importantly, the FAA and Boeing are handling it properly.

inferiorhuman 7y ago
Yes, but it's very long cycle failures at low frequency, and people suspect it's because of additional stress caused by winglets. Winglets reduce drag and save fuel, it's an important change. It may have been very difficult to predict and test this failure. And most importantly, the FAA and Boeing are handling it properly. Cracks have been found in NGs both with and without winglets, so that is almost certainly not the issue at hand.

notfromhere 7y ago

That's because when they merged with McDonnell Douglas, MD executives got the top spots in Boeing, so their shitty culture transferred over to the new company. The long-standing joke is that MD took over Boeing with Boeing's money