Tacking and gybing: turning through the wind.

The two maneuvers

The US Coast Guard Auxiliary defines a tack as turning the bow through the wind and a gybe (also spelled jibe) as turning the stern through the wind. Upwind, you change direction by tacking. Downwind, you gybe, or you head up and tack around instead. Both are core skills in entry-level courses: ASA 101 lists tacking and jibing among its required skills, and US Sailing's Basic Keelboat includes boat control in close quarters and open water. Where the wind is relative to your course is explained on points of sail.

Commands keep the crew together

A turn through the wind moves sheets, sails and often people, so the helm announces it first and waits for the crew to be ready. ASA teaches standard calls such as "Ready about" before a tack and "Prepare to jibe" before a gybe. The Coast Guard Auxiliary lists common tacking calls including "prepare to tack," "ready to tack?" and "hard alee" or "coming about." Wording varies by school and boat; what matters is that everyone aboard uses the same calls.

On bigger crewed boats the same idea scales up. The US Naval Academy's Navy 44 tacking guide assigns helmsman, grinder, tailer and working-sheet roles, and each crew member reports "Ready" before the helm calls the turn. US Sailing adds that at "Ready about" only one crew member should turn inboard to prepare the jib release while the rest keep hiking.

What makes a good tack

US Sailing splits a tack into two phases: the Turn and the Acceleration. It says most of the loss happens in the Acceleration. The key principles it gives:

• Carry speed, do not rush. The goal is to keep as much speed as possible through the tack, not to tack as fast as possible. Start with a slow, smooth turn, and turn faster in waves.
• Finish slightly low to build speed. US Sailing suggests coming out about 5 degrees below close-hauled in light air, about 3 degrees in moderate breeze, and right on course in heavy air.
• Time the jib release. Release it as it luffs or backs about halfway across the foredeck. Too early and it blows to leeward; too late and it acts as a brake.

North Sails adds two points. Ease the main a few inches to accelerate out of the tack, then trim back once at full speed. And in heavy air, turn slowly and only far enough to get the jib past the mast and shrouds. The Coast Guard Auxiliary notes a simple tack needs no mainsheet work at all, and that tacking in light air is harder.

Sources differ on waves. US Sailing says start the turn in a trough. North Sails says start as you climb a wave face. Both are aiming for the next wave to push the bow onto the new tack.

Why gybes need more care

A community sailing center handout from Ventura, California says that in a gybe the sails stay powered and the boom can swing across violently, which is why gybing is riskier than tacking and tacking is usually taught first. That handout is unattributed, so treat it as one center's teaching view. The Coast Guard Auxiliary separately warns that an accidental gybe can whip the boom across and hit the crew (see below). North Sails takes a balanced line: in all but the breeziest conditions a well-executed jibe is a safe and effective way to change tacks.

The principles North Sails gives for a controlled gybe are to start from a broad reach, call it in advance, turn slowly, pause on course when the wind is dead astern, control the main as it crosses, and correct the helm afterward so the boat does not round up in stronger wind. These are principles to practise under instruction, not a substitute for it.

When a gybe feels unsafe, the sources offer different answers:

• The Coast Guard Auxiliary suggests approaching from a slight broad reach to lower the risk in high wind.
• The Ventura community sailing center handout suggests tacking around instead.

Accidental gybes

The Coast Guard Auxiliary warns that an accidental gybe can whip the boom across and hit the crew. It names wind shifts and careless steering as causes, and notes that light winds from astern are hard to detect. Sail Magazine adds that squall wind shifts can cause one.

The common protection is a preventer, a line that holds the boom out on a run or broad reach. North Sails recommends using one when you are not intending to gybe, and releasing it as a planned gybe begins.

Gybing performance boats

For racing boats with spinnakers, North Sails' Viper 640 guide times heavy-air gybes to a wave so the sail load drops, and keeps the crew on the old windward side until the spinnaker fills. Pip Hare (Yachting World) writes that the lighter the wind, the faster the turn in a spinnaker gybe. Dinghy roll tacks and roll gybes are on dinghy technique.