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Unread 01-02-2009, 01:09
Greg Peshek Greg Peshek is offline
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Join Date: Feb 2006
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Re: For those who are skeptical about propellers - Team 2526

Quote:
Originally Posted by zrop View Post
Yeah, that's why we have a 3.5 multiplier on our props. So the 2.5 k rpms you get on a CIM motor at peak power output you don't have nearly enough pushing power. Our props are actually push them at about a walking pace.

See, ideally you reach 88% - 94% the speed of sound on the tips of your props in order to get maximum power.
Well, our blade/s pull too much power to gear it up any. We start tripping a 40A breaker at a 1:2 ratio. The size of our prop combined with the really high pitch, and the fact that the blade is cut to give a lot of thrust in one direction.. gave us a pretty good acceleration to around the speed you're describing at 3/4 ratio.

Of course we're going for different things. You have them for turning and maneuvering plus a good amount of power. And we're going for sheer power, mainly for getting across in a straight line fast, pinning, and then dumping.

Tell you what, you make it to Atlanta for Championships, we'll have an Overdrive style race.

-Greg