Morgans wrote:

"Jim Macklin" wrote in message
news:jsJqf.30375$QW2.4649@dukeread08...
They also used a high pressure sea level cabin,

I had never heard that. How did you dear about that?

I would imagine that a higher cabin would have slowed the cracks, but they
still would have formed.
--
Jim in NC


From what I recall from my younger Engr days:

Low cycle fatigue of metals is affected by:

1) Cyclic loading
2) Tensile mean stress
3) Local stress exceeding the material's yield stress

The bigger the values, the faster the crack initiation
or crack propagation...