Float Rigging

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Float Rigging

Postby mr157ifhz » Wed Jun 13, 2018 12:38 pm

A few questions on float rigging. I've a Rans S7s with Rotax 912s, to go on Full-Lotus 1450 floats. Pretty much have only settled on a couple things - Float angle to fuselage, and step distance from CG.
There are two things that I am undecided on:
Float stance - I am leaning towards a more narrow spacing center to center - say, 66" vs 72". Have read (was on this forum somewhere..AV8er?) that closer spacing will give better t/o performance than wider from the action of the bow waves ......is this just theory or did someone actually try a narrower stance vs wider?
Rigging Height - I'm thinking lower would be better. As long as good prop clearance from the water, a lower height, say 20~22", from the top of the floats to the fuselage would work better than 24 or higher (Murphy Rebels on floats seem to be almost 3ft!) Less pendulum effect, closer to water so more ground effect, lower CG increasing stability somewhat to offset the stability lost by going narrower on the stance, shorter rigging would = lighter weight too. Oh, and maybe no step needed to climb aboard.
Thoughts?
-Matt
mr157ifhz
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Re: Float Rigging

Postby mr157ifhz » Fri Jun 15, 2018 2:28 pm

Pretty much have the info I need now after reading about float installation trials and tribulations on this and various other forums. Going to go 66" c to c, 22" Height and a 3* throat angle - will start there and see how its goes.
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