Prop tip speeds

[Rex R]

some time back I was reading about ships...and ran across a bit where they mentioned that foils moving faster than 50mph had massive cavitation. got curious last nite a ran some numbers...for a 30mm prop a tip speed of 50mph works out to 15k rpm(10k for a 40mm), then I tried 25k which = 87.5mph, for a 40mm prop 87.5mph works out to 18500 rpm...which is about what the sv runs... just thought it was interesting.
rex

[ReddyWatts]

Get with the guy at abc props. He likes to talk about prop tip speed, then you can explain it to all of us.