About
Who built it
A skipper who wanted to think through a manoeuvre at their own berth before doing it. Operator details are in the imprint.
The physics in plain language
The boat moves forward, sideways and turns. Water resists each motion along the hull, the keel and rudder make lift, the propeller pushes with a delay and walks the stern, wind pushes on the topsides, and every line is a spring that only pulls.
Limits
Plausible behaviour at harbour speeds of 0–4 knots, not a guarantee. Waves, heel and shallow water are not modelled. Always keep a margin.
Privacy
No account, no cookies, no tracking. Saved berths stay on your device; share links carry everything in the address.