Originally Posted by
Genghis the Engineer
Metal fatigue has been understood pretty well since the investigations into some major railway disasters in the 1880s. What the Comet disasters taught us was about fatigue in pressurised aluminium structures - very much about the initiation mechanisms.
Quite right of course, the Comet issue was specific in that sense. I think the Comet-Shute relationship mix for me was because at the public enquiry the prosecuting(?) lawyer of the time cited
No Highway at the outset of the proceedings - probably a bit of theatre to some extent but I guess it impressed me somewhat when I read that.
There isn't anything about the Tomahawk's mainspar life that wouldn't have been understood by a good aeronautical engineer in the 1930s - but it is what it is.
I agree that fatigue per se had been understood for some time but I'm not sure it was especially well understood in terms of aircraft at that time? There are many instances (Northwest 421 in 1948 [publication year of
No Highway], and Aloha 243 forty years later, just to name a couple) that would suggest perhaps not.
At least with the PA-38 someone's thought about it beforehand and, looking at the AD, they've done so with a degree of science. Let's hope that works out in practice.
effortless: Anyone ever wonder why we called it the Traumahawk. Wobbly prop is one thing but wobbly empennage?
I shared my initial training between a DH-82 and a PA-38 and can well recall after my first stall/spin session with the PA-38 saying to the instructor 'how many people don't come back after
that!'. So maybe its flight characteristics have just traumatised a good number along the way...
FP.