What does a boat have to do to complete the course?
B · Beginner · Racing and scoring · 2 of 5A boat must start, pass each mark on the required side and in the correct order, and finish. The test is a string laid along the boat's track and pulled tight: it must pass every mark on the right side. A boat may go back and correct a mistake as long as it has not finished.
How it works
A boat sails the course when:
- it starts;
- a string representing its track until it finishes, when drawn taut, passes each mark of the course on the required side and in the correct order, touches each rounding mark and passes between the marks of a gate from the direction of the previous mark; and
- it finishes.
- What a mark is: an object the sailing instructions require a boat to leave on a specified side, and a race committee vessel from which the starting or finishing line extends. An anchor line is not part of the mark.
- Other marks: a mark that does not begin, bound or end the leg a boat is sailing has no required side for that boat.
- Correcting an error: allowed at any time before the boat finishes.
- The course: stated in the sailing instructions or signalled by the race committee no later than the warning signal.
- Getting it wrong: a boat that did not sail the course is scored NSC, with the same points as a boat that did not finish.
Tricky cases
A boat passed a mark on the wrong side. Is its race over?
No. It may correct the error, provided it has not finished. It has to unwind and round the mark so that the string test is met.
Does a boat have to round a mark of a leg it is not sailing?
No. A mark that does not begin, bound or end the leg the boat is on does not have a required side.
Can the race committee score a boat as not having sailed the course without a hearing?
Yes. That is one of the scores the race committee may give without a hearing.
Why the rule exists
A boat's wake leaves no line to inspect, and boats loop and double back. The string image settles every argument about a tangled track: only the net path counts.
Where it differs
| Where | What changes | Source |
|---|---|---|
| Racing Rules of Sailing | As above | RRS 28; RRS Definitions (Sail the Course, Mark) |
| Each event | The course, the marks and the sides are set by the sailing instructions | RRS 27.1; RRS Definitions (Mark) |
From the rule book
World Sailing The Racing Rules of Sailing 2025-2028, rules 27.1, 28, A5.1 and A5.2 and the Definitions (Mark, Sail the Course). In force from 1 January 2025. Checked 14 October 2026. Official document: The Racing Rules of Sailing 2025-2028 (PDF).