Quote:
Originally Posted by BlackBerry
XP-51G max level speed=495 mph, P-51D=442 mph.
If everything being equal, XP-51G need (495/442)^2= 125% engine thrust of P51D. Obviously, 2200HP Rolls Royce RM-14SM is around 125% output of 3000 RPM and 67" stanard Merlin(1760HP at altitude).
Roughly, we can say Britain Rotel 5-balde wood propeller is as effective as those 3-4 blade CSP at speed envelop. Namely, around 80% efficiency at 495mph=800km/h TAS.
It seems that allied believed in wwii that 4 or 5 blade propellers are better than 3-blade when speed is high(>700km/h?).
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It is interesting to note that there was also attempts to switch back to 3 bladed-prop during the developpement of the famous P51.
The lightweight XP-51F, just as XP-51G, is a completely new design, NOT a modified P51D: can we just compare them to the D series?
The XP-51F apparently used a 3-bladed hollow Aeroproducts prop in 1944 for max speed of 491 mph.
Would be interesting to know more about this propeller too.