[Leandros]

Originally Posted by GreyBeard

But not flank speed. I always found that confusing. Why is it called full speed when it is not really full speed, but flank speed is?

Ok, I am with you on this one - "full speed" is, I believe, something you can live with for a reasonable time while flank speed is really a sort of emergency effort. It was the same with aircraft piston engines at the time. 5 minutes was often set as a maximum but some engines could take it better than others. In a deplasement boat it really means very little regarding what you get out of it. When you have reached the ideal hull speed it takes so very much to increase it. In a aircraft it did, as in a climb with already reduced speed. In aircraft engines it was often coupled with water-methanol injection from a separate fuel tank. The Griffon engines in the Typhoon and Tempest were known to be more sensitive to overboost than, say, the Rolls-Royce or Allison V-12 engines. Simply because the Griffon was more powerful.

Fred