feet ( 12 x 5280 feet)
I got lost on the prop braking formula-
If I understand you - you are considering the engine reaches some peak rpm and the prop speed also becomes fixed there.
prop efficiency is figured at 140%?
why?
The prop does act as a brake but simply going by pitch numbers , I get hopelessly lost
two different brand 22x8 props on my 50 cc engine act completely differently
One does 7750 static and 8400 level flight atmax airspeed the other does 6700 static and 7600 level flight max airspeed
I don't know the difference in max airspeed but the slower revving one feels faster!
IF--- I were to try for a terminal V dive it would likely be terminal for something -but I suspect the faster revving prop -in this case -- would be braking more than the slower one .
To sum up
I can see how a given prop could be calculated to act at a brake IF it held at a given rpm -I just don't see that happening on most setups the two strokers will rev pretty freely-at least mine will
Did I miss the point of the question?