Hull speed: the wave wall at 1.34×√LWL, what it takes to break it, and the ratios that predict any boat — free marine math.
The displacement-hull speed limit: 1.34 × √LWL — why your boat stops accelerating, with the wave physics that builds the wall.
Hull speed from waterline metres: 2.43 × √LWL(m) — the same wave wall in the units most of the world's boats are documented in.
Horsepower to drive a displacement hull near its limit — Gerr's lb-per-hp curves turned into a planning tool, with the brutal last-knot price list.
The D/L ratio that classifies every hull from ultralight flyer to heavy cruiser — computed, banded and explained.
Paddle-craft speed limits: hull speed for kayaks and canoes, what a paddler's half-horsepower actually achieves against it, and why longer boats win races.
Ted Brewer's tongue-in-cheek-turned-canonical comfort ratio: how corky or steady a boat feels in a seaway, from displacement, length and beam.
Bore, stroke and cylinder count → cc, litres and cubic inches — plus bore/stroke ratio and what over-boring or stroking actually buys.
Past the wall: Crouch's planing formula for speed from power and weight — with the hull-constant table for runabouts, cruisers and racers.
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