Heli tack step by step: luff up, back the sail, switch your feet and let the sail rotate – with timing mistakes, space needed and safety rules.
What is a heli tack in windsurfing? It is a tack in which you do not walk the sail around the mast but let it rotate in place: you luff up into the wind, push the sail backwinded (the wind pushing against the sail from the wrong side) into the wind, switch your feet and let the sail rotate clew-first through the wind [1].
The honest answer about difficulty: the heli tack is neither a beginner move nor a pure show trick. It is the bridge between the classic tack and freestyle moves. Its advantage: it avoids the hardest part of the normal tack, switching the sail around the mast, especially on small boards [1]. Its price: timing. Fast tacks and heli tacks usually fail because of timing, not strength [1].
We classify it as "intermediate". If you can only do the basic tack, master that skill first and learn this move on a big board in light wind.
Sail on a beam reach to a light close-hauled course with speed. If you are in the harness, unhook beforehand [1].
Milestone: you hold your course and sail calmly.
Move the sail past your body to the back until the boom end points at the water. Beforehand slide your hands forward on the boom toward the mast – that makes the sail easier to push [1].
Put the front foot directly in front of the mast and the back foot on the centreline. Keep luffing [1].
Luff until the board points directly into the wind. The bow sits against the small waves and the board has almost no speed. The foot of the sail touches your shin. Now the movement turns from "against the wind" to "with the wind" [1].
Keep the sail arm bent so the sail stays open and rests loosely on the boom. Extend the mast arm to hold the mast away from your body [1]. Do not push against the sail, otherwise counter-pressure builds up, the mast rises and the sail throws you backward into the water [1].
As the sail rotates, bring the mast back upright so the mast arm pulls the sail toward you [1]. Switch your feet now. In the faster variant after Bartholdi [2] your feet must be in position before the clew passes through the wind, and your heels stay on the board during the backwind section.
Grab the mast with your free hand just below the boom, then the other side of the boom. Both hands on the boom, sheet in, adjust the board with your feet and sail away [2].
Practise the heli tack first in 5 to 10 knots on a wind-SUP or longboard before you try it on the small board [1]. The big board forgives it when you are too early or too late at the apex – and you get a feel for the moment when the sail "lets go".
A tack without changing sides around the mast: you luff up into the wind, hold the sail backwinded, switch your feet and let the sail rotate clew-first through the wind. It avoids switching the sail around the mast [1].
Light wind of about 5 to 10 knots is ideal, on a big board such as a longboard or wind-SUP [1].
Usually you push against the sail or throw it into the wind. Then counter-pressure builds and the rig throws you back. Keep the sail arm bent and let the sail rest loosely [1][2].
At least one mast length all around, about 4 to 5 metres for normal sails. Without that room the manoeuvre is unsafe [2].
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