Track has two distinct meanings on a sailing boat, and both are in daily use. 1. A track is a metal rail on the deck, mast or boom that carries sliding hardware: the genoa cars that set the sheet lead, the traveller car under the mainsheet, the slides that hold the mainsail luff to the mast, and the foot slides along the boom. 2. In navigation, track is the path the boat actually follows over the ground, or the intended path drawn on the chart between waypoints, as opposed to the heading the compass shows. A beginner needs to know which meaning is meant; an experienced sailor uses both without thinking and knows that getting the genoa car right on the first and keeping the boat on the second are much of what good sailing is.
Track as sail-control hardware
Deck and spar tracks are extruded aluminium or stainless sections, usually T-shaped or with a captive channel, bolted through the deck or riveted to the spar. A car or slide runs along the track and is fixed in position by a pin, a screw or an adjustment line. The main types are these.
- Genoa or jib sheet track: Runs fore and aft along the side deck. The genoa car on it carries the sheet block, and its position sets the lead angle to the clew. Moving the car aft opens the leech and flattens the foot; moving it forward closes the leech and adds depth to the foot.
- Mainsheet traveller track: Runs across the cockpit or coachroof. The traveller car sets the angle of the boom relative to the centreline independently of the mainsheet tension, which controls twist.
- Mast track: The groove or external rail on the aft face of the mast into which the mainsail luff slides or bolt rope feed. Batten car systems run on a dedicated external mast track to reduce friction on fully battened mainsails.
- Boom and pole tracks: The groove along the boom for the mainsail foot, and the vertical rail on the front of the mast that carries the inboard end of the spinnaker pole so it can be raised and lowered.
Why track position matters for sail shape
From a sailmaker’s point of view, the genoa track is the most important control on the boat after the halyard and sheet. The sheet lead determines the split between leech tension and foot tension, and therefore how the sail twists. UK Sailmakers designs a headsail for a particular lead angle, and the telltales up the luff are the way to check you have it. If the top telltales stall before the bottom ones, the lead is too far forward and the leech is too closed; if the top luffs first, the lead is too far aft. Move the car until all the telltales break together, then mark the track.
The mainsheet traveller does for the main what the genoa car does for the headsail. Sheet tension controls twist; traveller position controls angle of attack. In light air, pull the car up to windward and ease the sheet to get the boom near the centreline with an open leech. In a breeze, drop the car to leeward to spill power without losing leech tension.
Track as course made good
In navigation, the distinction between heading, course and track is fundamental. Heading is where the bow points. Course is the direction you intend to travel. Track is the direction you actually travel over the ground once tide, current and leeway have done their work. On a chart, the intended track is the line drawn between two waypoints; the ground track is the line the boat actually made. A GPS reports course over ground, which is the same thing as the instantaneous ground track.
The gap between heading and track is the sum of leeway – the sideways drift of a sailing boat through the water, typically three to eight degrees upwind – and the set of the tide or current. The navigator’s job when shaping a course is to work backwards: start with the track you want, allow for tidal set and leeway, and arrive at the heading to steer. Chartplotters do the sums, but every skipper should be able to do them on paper.
Frequently Asked Questions about Track
How do I know where to set the genoa car?
Use the luff telltales. Sail upwind and slowly luff the boat: if the top telltales lift first, move the car forward; if the bottom ones lift first, move it aft. When all three lift together, the lead is right for that sail and wind. Mark the track.
What is the difference between heading, course and track?
Heading is where the bow points; course is the direction you intend to make good; track is the path the boat actually follows over the ground after tide, current and leeway. Steering the heading that produces the desired track is the navigator’s basic problem.
Whether you are sliding a car along a rail or laying a line across a chart, track is about putting things exactly where they need to be. Set the leads to the telltales, mark the positions, and shape a course that makes good the track you intend, and both meanings of the word will be working for you.