dirtstrip wrote:Here is a US company's online calculator.
I've run some different prop diameters and rotation rates through this calculator, but end up with different results when I plug in the same numbers on a different online calculator over at Pponk's site http://www.pponk.com/HTML%20PAGES/propcalc.html . Then over at the Hoverhawk site's calculator, it has commentary that suggests that between .88 and .92 Mach is the redline and tip speed should be below .88, while Pponk's site suggests that between .88 and .92 Mach is the most efficient tip speed.
Is there any definitive, reliable tip speed/prop pitch calculator out there? I want to put a fairly big prop out front on the new RR, and utilize all 6300 engine rpms available for the best climb out performance. Any of you guys have any suggestions?
parameters I have used so far are:
2 bladed prop
max engine rpm: 6300
available gear box ratios are: 2.16:l, 2.29:l, 2.59:l
average ambient temp 90F