Roll gybe for experienced dinghy sailors: how heel and weight support the gybe, what rule 42.3 allows and when a speed gybe is the better choice.
The honest answer upfront: the roll gybe is a gybe in which you use heel and body weight deliberately so that the boom crosses cleanly and the sail pulls immediately afterwards – but in many situations it is not the best choice. The racing rules explicitly allow you to exaggerate the rolling in a gybe as long as the boat, just after the gybe, is not faster than it would have been without the gybe [1].
The roll gybe is a tool for light and medium wind, not for all wind.
This guide gives you an overview of the idea. Gybing in a lot of wind and the accidental gybe belong in sailing school, not in a guide.
RYA teaching describes the gybe like this: the helmsman sits forward of the tiller, boat on a training run, centreboard only slightly down, mainsheet in, then he pushes the tiller, the boom swings across and the weight comes to the new side [2]. Milestone: you gybe three times without problems.
In RYA teaching (from sailing without a rudder): heeling to windward makes the boat bear away, heeling to leeward makes it luff up [2]. In the gybe you want to bear away, so a slight heel to windward supports the turn. Milestone: you explain why heel turns the boat.
Go into the gybe with speed. RYA teaching recommends gybing at speed because it reduces pressure on the rig and makes the turn smoother [2]. Milestone: the boat has speed before the gybe.
On a centre-mainsheet boat, pulling on the sheet at the right moment helps bring the boom across positively [2]. Then the helmsman brings tiller, boom and weight to the middle at the same time [2]. Milestone: the boom comes across under control, not with a bang.
Bring the boat flat, set the sail, change hands. Milestone: the sail pulls immediately and the boat runs stably.
in the first session you do ten normal gybes in light wind and concentrate on speed and the call. In the second session, just before the gybe, you deliberately take some heel to windward and feel how the boat bears away. In the third session you bring the boat flat again immediately after the gybe. In the fourth session, in slightly more wind, you compare the roll gybe with a fast, flat gybe and decide which suits your boat. Have yourself filmed and discuss the sequence with your instructor.
The gybe is the manoeuvre in which the boom changes sides fastest. For beginners and recreational sailors, injuries often result from impacts with the boom and equipment during manoeuvres [4]. A review names strong wind and inexperience as common factors in fatal sailing accidents [5].
This guide explains and motivates, but it does not replace supervised training with an instructor.
For context (practical assessment): the roll gybe is the counterpart of the roll tack and builds on the same idea of steering the boat with your own weight. It is riskier, however, because the boom crosses with more force in a gybe than in a tack. So practise it only when your tack and the normal gybe are secure, and increase the wind only once the manoeuvre runs calmly in light wind.
Practise the gybe first with a call: “Stand by to gybe” and the crew's answer. RYA teaching deliberately separates the commands from those of the tack to avoid confusion [2]. Only when the call is in place do you add rolling and weight.
A roll gybe is a gybe in which you use heel and body weight deliberately so that the boom crosses cleanly and the sail pulls immediately. In racing the rolling is limited by rule 42.3(b) [1].
In racing yes, within narrow limits: rule 42.3(b) allows exaggerating the rolling in the gybe if the boat, just afterwards, is not faster than it would have been without the gybe [1].
In a lot of wind a US coach of the U20 class advises a “speed gybe” instead of a roll gybe [3]. That is a class-specific hint. For your boat you clarify it with your instructor.
Master the normal gybe first, practise in light wind with an instructor and build up the rolling slowly. RYA teaching recommends gybing with speed and keeping movements smooth [2].
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