The story about life expectancy earlier was repeated to us at nav school. And it came to pass.
One of the first to go was in a Vulcan, one of the first Mk 2s to crash in '64. Then we had the usual Canberra practice asymetric - the Vulcan was practice asymetric too.
By the time the 38/16 point arrived we had lost half.
Then at the home of air defence, when we lost an F3 we were all shocked to the core as it had been like an airliner up until then. Probably flew like one too