Sailforce – Learn to Sail

Explain sail trim without a whiteboard: course, wind and sheets live on screen. Go Pro for the 3D yacht: tacks, gybes and a cutaway through the sail. Works offline.

Explain sail trim without a whiteboard or chalk: Sailforce shows course, wind and sheets in real time – on iPhone and iPad, at the dock or under way.

For skippers who want to show their crew why a sail has to be trimmed just so. And for anyone learning to sail – before or after a sailing course.

FREE: THE 2D TOP VIEW • Course ring to steer, the wind always comes from the top • Jib sheets port and starboard, mainsheet • Wind triangle: true wind, boat wind and apparent wind • Arrows for drive, side force and the resultant, plus keel and rudder force • Trim tips in plain words, e.g. "Jib luffing · haul the sheet", "Jib aback · ease the windward sheet", "In irons · bear away" • Wind strength from 0 to 40 knots, shown in knots, km/h and Beaufort • A preview of the 3D yacht: it sails a demo round with a tack and a gybe

SAILFORCE PRO: THE 3D YACHT • A 3D charter yacht to orbit and zoom, which you steer and trim yourself • Physics tuned to polar data of 12 m cruising yachts: heel costs speed, the boat speeds up and slows down with momentum • Tacks and gybes in real time, with the loss of speed; in a gybe the boom swings across • Wing on wing downwind, with a warning before an accidental gybe • A textbook cutaway through the sail: streamlines, suction and pressure in colour, adjustable height • Stability: weight and buoyancy as arrows, plus the righting lever • Keel and rudder visible under water, with their forces • Wake trail, waves and animated wind lines

ON BOARD • 12 languages: English, German, Polish, French, Italian, Spanish, Dutch, Czech, Croatian, Swedish, Danish, Norwegian – follows your device language, can be changed in the settings • No account, no tracking • Works offline; only purchases and restoring them need an internet connection

PRICES • Trip Pass, 1 week: €3.99 (one-time purchase, does not renew) • Sailforce Pro monthly: €8.99 per month • Sailforce Pro yearly: €24.99 per year Prices in other countries are set by the App Store and may differ.

Payment is charged to your Apple ID at confirmation of purchase. Subscriptions renew automatically for the same period at the same price unless cancelled at least 24 hours before the end of the current period. You can manage and cancel them at any time in your Apple ID settings. The Trip Pass ends by itself after 7 days.

Terms of Use: https://positivelifeapps.io/en/sailforce/terms/ Privacy Policy: https://positivelifeapps.io/en/sailforce/privacy/

A NOTE ON THE PHYSICS Sailforce is a teaching model calibrated to a typical 38–40 ft charter yacht. The speeds shown are guide values. On your boat, these all play a part: boat type and hull shape, load, sails and their condition (roller furling, reefs), waves, current, a fouled hull, gusts and wind shifts, and how well the crew trims and steers.

Sailforce is a teaching tool – not a navigation aid and not a substitute for a sailing course.