03-05-2020, 08:08 PM
That would have to be the longest intact crack ever discovered! There is a huge statistical scatter in metal fatigue. Items never overloaded often have shorter lives (The Comet test aircraft was overstressed and led to very wrong life fatigue predictions). It may not be the original crank. Parts could have been substituted t a low mileage for various reasons (My car had an exchange engine by 1940 and 40,000 miles). Steels and the heat treatment etc were not as controlled as now. may have ben cracked by some factory straightening correction (as seems to have occurred with many Javelin cars)