Boat & Marine Engine Toolkit

Boat & Marine Engine Toolkit is a professional calculator suite for boat owners, marine engineers, naval architects, ship captains, and offshore platform crews. Run every calculation fully offline — at the dock, at anchor, or miles from the nearest cell tower. No ads, no accounts, no subscription. From sizing ground tackle for a blow to checking prop shaft torque before sea trials, the toolkit puts trusted marine engineering formulas in your pocket and keeps them there. WHAT'S INCLUDED: Navigation & Anchoring - Hull Speed Calculator — compute theoretical hull speed and speed/length (S/L) ratio from waterline length for sailboats, trawlers, and displacement craft. - Anchor Chain Scope — plan rode length from water depth, bow height, and tide for safe overnight holding. - Anchor Pull Strength — estimate working load on your anchor and rode from wind, current, and vessel windage. Propulsion & Drivetrain - Prop Shaft Torque — calculate shaft torque from engine horsepower and shaft RPM for gearbox and coupling sizing. - Hydraulic Cylinder Force — push and pull force from bore, rod diameter, and system pressure for steering, hatch, and deck gear. - Fuel Burn & Range — project fuel burn, cruising range, and reserve from tank capacity, GPH, and cruise speed in knots. Safety & Compliance - Bilge Pump Sizer — size pump capacity against hull volume with ABYC-aware guidance for peace of mind. - Bollard Spacing — lay out dock and deck bollards with clean spacing for mooring lines and bollard pull loads. Reference Tables - Beaufort wind scale, anchor scope ratios, shackle working loads, and more — the numbers you actually reach for on deck. WHO IS IT FOR: - Boat owners planning passages, provisioning, and ground tackle - Marine engineers sizing drivetrains, hydraulics, and auxiliaries - Naval architects sanity-checking hull displacement and S/L figures - Ship captains and mates running quick bridge calculations - Offshore platform crews and workboat operators on deck - Marine surveyors documenting condition and compliance notes WHY MARINE PROS LOVE IT: - 100% offline — every calculator runs on-device, so you never lose a tool when you lose signal offshore. - No ads and no tracking — clean, focused screens built for use at sea. - No subscription — pay once, own it, use it on every trip. - Instant results — type values, get answers, move on to the next job on the checklist. - Professional formulas — ABYC-aware guidance, standard naval architecture equations, and clear unit handling (knots, meters, feet, psi, bar, kW, HP). ONE-TIME UNLOCK: Unlock All Calculators is a single $19.99 USD in-app purchase. It is a one-time, non-consumable unlock — not a subscription. One payment opens every Pro calculator and every reference table, forever, on your Apple ID. Prop pitch planning, shaft torque, bilge pump sizing, bollard pull layouts, Beaufort references — all in. Stow it in your pocket, keep it on the bridge, or pin it to the engine room iPad. Boat & Marine Engine Toolkit is built to be the quick, quiet answer to the everyday marine engine and offshore questions that keep boats running and crews safe.