Colyn: I just re-read that article, Busch states:
(The head's tensile strength is reduced to 50% of its room-temperature value at a CHT of 400F, and to about 33% at 500F.)
I don't see that supported in any literature studying the properties of steel versus temperature. There appear to be small changes in elasticity,strength of a few percent in the range we fly in but it appears that big changes need to be in the 500-900C range. I'm not convinced that Busch is right on this one.
Paul
Legacy (cylinders currently at room temperature and high strength)