5 Marine Engineering Tools

Marine Engineering & Buoyancy Calculators

Verify ship displacement tonnages, estimate theoretical boat speeds and propeller slip, evaluate hull speeds (planing vs displacement), calculate fuel burn rates, and determine line breaking strengths.

Hull Speed & Power

Estimate maximum displacement hull speeds (LWL formula) or calculate planing hull speeds using Crouch's classic marine formula.

Hull Hullform Options

Note: Waterline length is shorter than overall length (LOA).

Engineering Report

Real-time Calculations
Maximum Displacement Hull Speed
8.04Knots
Equivalent to 9.25 mph.
The Physics of Hull Speed

Displacement hulls are limited by the wavelength of their own bow wave. When the bow wave wavelength matches the Load Waterline Length (LWL), the boat sits in a trough, requiring exponential horsepower to climb over this wave (the bow wave speed barrier).

Recommended minimum auxiliary power for a 8.04 ton vessel: 33 HP (based on 4 HP/ton).

Quick Formulas Summary

Archimedes VolV = Mass / Water Density
Theoretical KnotsKnots = (Pitch * Shaft RPM) / 1215.22
Hull Speed LWL LimitKnots = 1.34 * sqrt(LWL_ft)
Crouch Planing SpeedKnots = C / sqrt(Lbs / HP)
Line Break MBSMBS = strengthFactor * d² * 0.25

Explore Additional Utilities

Soil Permeability Converter

Convert coefficient of permeability (hydraulic conductivity) between cm/s, m/day, ft/day, and m/s with soil type drainage classifications.

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Solar Panel Output & Yield Calculator

Calculate daily and annual electricity generation (kWh) based on solar panel capacity (kWp), peak sun hours, and system efficiency losses.

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Crown position ↔ function — hand setting vs winding

Map out the mechanical state and winding functions of crowns at positions 0, 1, and 2, including quickset dates and hacking.

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Telescope Magnification Calculator

Calculate telescope magnification, exit pupil, and resolving limit from focal lengths and aperture.

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Wind Chill Calculator

Determine the feels-like wind chill index from ambient air temperature and wind speed.

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Yarn Weight Converter

Convert yarn sizes across WPI (Wraps Per Inch), ply, and standard weight categories.

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Layer height ↔ print time estimator

Estimate 3D print duration changes and total layer counts when switching layer heights and print speeds.

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Sample size calculator — confidence level ↔ margin of error

Determine required sample sizes for research surveys or experiments based on population size, confidence levels, and target margin of error.

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Equatorial Coordinates Converter

Convert Right Ascension (RA) and Declination (Dec) to Hour Angle and Alt-Azimuth coordinates.

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AWG Cable Sizer

Convert American Wire Gauge (AWG) sizes to metric dimensions, and estimate current carrying capacity.

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IV Drip Rate (Drops/min ↔ mL/hour)

Convert IV flow rates between mL/hour and drops/minute (gtt/min) for any drop factor, with real-time dripping rate animation.

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Current Speed Converter

Convert tidal, ocean, and river current speeds between knots, meters per second (m/s), and kilometers per hour (km/h).

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Soil Plasticity Index Calculator

Calculate Plasticity Index (PI) from Liquid Limit (LL) and Plastic Limit (PL), and interpret soil state using the Atterberg limits chart.

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Watch beat rate — BPH ↔ Hz ↔ vibrations per hour

Convert mechanical watch balance wheel frequencies between Beats Per Hour (BPH), Vibrations Per Hour, and Hertz (Hz).

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True wind ↔ apparent wind

Calculate apparent wind speed and angle from true wind speed, sailing angle, and boat speed (or vice versa).

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Hyperfocal Distance Calculator

Calculate hyperfocal distance, near sharp limit, and depth of field range starting point for any focal length, aperture, and sensor format.

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Sidereal Time Converter

Convert between standard Solar Time and Sidereal Time based on your longitude.

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Servo angle ↔ PWM pulse width

Convert between servo rotation angle in degrees and standard PWM pulse width in microseconds, with continuous rotation presets.

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dBm to Watts/Volts

Convert RF power levels between dBm, milliwatts, watts, and RMS voltage across 50/75 ohm impedance.

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Board feet ↔ cubic meters ↔ cubic feet — lumber volume

Convert lumber volume measurements between Board Feet, Cubic Feet, and Cubic Meters.

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