Up in West Hollywood where I work, there is no shortage of queens, but I thought it was high time to broaden the definition, Moth-style, in celebration of the prodigal mainfoil's return from the tank:
For reference, I post the Prowler numbers from Bill's earlier work with John Zseleczky, which was the most efficient foil in that paper (vs a Bladerider mainfoil) for 20fps and 18" immersion, 180lb load:
The two foils are the same area and span. Different 2D foil sections on lifting surfaces; struts should be the same shape but ended up different due to (my) operator error in building the thing. An old photo:
I feel good about these results; they confirm a lot of what I thought in the design stage and what I have sensed on the water, but could not state conclusively until now. I think it is good news for the class in general, because it shows if nothing else that there may be a way to get quite a bit more efficiency out of the boat.
I hope these data will serve as an impetus to anyone who might have been thinking about going completely flapless to get busy on a prototype, as the control system design isn't a particularly easy nut to crack! Sounds like J. Bethwaite et al may have something up their sleeves in this regard; should be interesting to see how our next iteration compares to their design. I have a date with the Shop Bot next weekend and hope to get a new system mocked up before July.
Major thanks to Bill Beaver for once again helping to shed some light on the behavior of these cool little boats.
Major thanks to Bill Beaver for once again helping to shed some light on the behavior of these cool little boats.
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