Speed–Power Performance
Speed–power curve and achievable-speed prediction
Operating data
Hull parameters come from the Resistance module (import its JSON first, or enter values).
Speed range
Propulsive efficiencies
Available power
Power-chain & MCR margins
Sea (service) and engine margins compound on brake power to give the required installed MCR at the design speed.
Engine–propeller matching
Load diagram: the propeller demand line P ∝ n^p crossed against the engine torque/power envelope gives the matching operating point.
Fuel & endurance back-calc
Across the swept speed range, endurance (days) and range are derived from required power and tank capacity.
Environmental conditions
Adds wind resistance + added resistance in waves (STAWAVE-1 head sea) to the calm-water resistance at the target speed.
Prediction results
MCR power-chain decomposition (design speed)
Effective power grows to the installed MCR through hull/propulsion, shaft and the sea & engine margins.
Speed–power curve
Engine load diagram
Speed sweep table
Endurance / range over the speed range
Environmental added resistance & power (target speed)
Wind R_air and added wave resistance R_aw (STAWAVE-1) added to the calm-water resistance; the delivered-power increase is shown at the target speed.
- • Achievable speed found where the delivered-power curve equals available delivered power.
- • Endurance at each speed = tank ÷ daily burn; range = endurance × speed.