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Jeff Higgins Jeff Higgins is online now
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Join Date: Mar 2004
Location: Higgs Field
Posts: 22,807
Quote:
Originally Posted by Flieger View Post
Cracks are nothing new in airplanes. They have a designed lifetime. After they are worn out the cracks can become unstable and cause fracture. Prior to that the cracks are not harmful. If we made them stout enough not to fatigue they would be too heavy to fly. If made from metal.
Simply untrue in every regard.

Quote:
Originally Posted by Flieger View Post
appears that they may have miscalculated the stresses the wings would see and so they may be fatiguing early?
That's it in a nutshell.

Quote:
Originally Posted by Flieger View Post
Or maybe they are just checking to confirm the cracks are progressing as expected.
No. There is, essentially, no predicted, much less allowable, cracking in any structural component of an aircraft. These are entirely unexpected, and must be repaired.


Quote:
Originally Posted by J P Stein View Post
Odd....ALL formed or machined parts we made at BOP are non-destructive tested. ANY/ALL parts showing actual cracks are scrapped by engineering without exception....in my experience.
Many parts on our aircraft are indeed subject to non-destructive testing or, more accurately, non-destructive inspection. Most are not. Once past initial development and certification, many parts are certified by the process used to make them, rather than checking each and every individual part.

Airbus is facing potentially very, very big problems with this. I won't go into everything, but suffice to say we are keeping a very keen eye on this. It doesn't look good for them.
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Jeff
'72 911T 3.0 MFI
'93 Ducati 900 Super Sport
"God invented whiskey so the Irish wouldn't rule the world"
Old 01-20-2012, 08:07 PM
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