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Three-point hydroplane

Name: Three-point hydroplane dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

What is a three-point hydroplane? · Standard part · basis: Design rules and figures from the cited sources; example geometry by Xem Studio

Also called: three point hydroplane, hydroplane boat, rc hydro, prop rider, sponson hydroplane, unlimited hydroplane, 3 point hydro, hydro setup, rc hydroplane sponsons, outrigger hydro

Exact dimensions. True size, with no printing tolerance added.

sizes: 4 in table

Notes

A three-point hydroplane rides on two forward sponsons and the lower half of its semi-submerged propeller, lifting most of the hull clear of the water (Wikipedia).
Lift at speed comes from planing forces, not buoyancy. The design set records such as Slo-Mo-Shun IV's 160.323 mph in 1950.
RC hydro set-up centres on strut angle, tail weight and turn-fin angle (Model Gas Boats).
Used on: Slo-Mo-Shun IV, Spirit of Australia.
The file is a reference example built by Xem Studio from the numbers above (Reference RC mono: 585 mm length and 20 deg transom deadrise (SV Design Stealthwake data); 181 mm is an unlabelled width in the same source's deadrise diagram.). Sizes the sources do not fix are illustrative; scale the example to your own vehicle.

Three-point hydroplane size chart

parameter	value or range	source
Slo-Mo-Shun IV record	160.323 mph (1950)	Wikipedia
RC strut angle (manufacturer default)	0 deg	Model Gas Boats
Strut shim, 1.75 in strut	0.030 in per 1 deg	Model Gas Boats
RC rudder	90 deg to table unless specified	Model Gas Boats

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Wikipedia	Hydroplane (boat)	web	Publisher's page; dimensions are facts
Model Gas Boats	Some tips on setting up a hydroplane hull	web	Publisher's page; dimensions are facts

Free files

★ Free files 1 parts. Xem Studio design: free to use, print and sell things from; not to be republished as files. Xem Studio Design License. index.json

three-point-hydroplane-hull

Three-point hydroplane: centre hull + two forward sponsons, 585 × 181 mm (illustrative)

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Plain text: sheet.txt · JSON: /api/geometry?object=three-point-hydroplane