Rule 29: Recalls and Being Over Early (OCS)
Rule 29 of the Racing Rules of Sailing 2025-2028 covers recalls. If any part of a boat's hull is on the course side of the starting line at her starting signal, she is over early, or OCS. The race committee signals an individual recall, and she has to return to the pre-start side and start again.
Rule 29.1 is the individual recall. The committee flies flag X with one sound and keeps it up until every early boat is back, for up to four minutes after the start. Only the boats that were over go back; the race goes on.
Rule 29.2 is the general recall, for when the committee cannot pick out the early boats or the start went wrong: the whole start is sailed again. SailMOB calls an early boat back on her own; it has no general recall.
Going back costs you the start, so aim to hit the line at full speed just after the gun, not sit on it at the gun. While you return, rule 21.1 has you keep clear of every boat that started properly, whatever your right of way would otherwise be.
Sail it
One boat is over early at the gun, the other starts cleanly below it. Sail the early boat back, restart, and keep clear while you do.
Questions
What does OCS mean in sailing?
On Course Side: some part of the hull is over the starting line at the starting signal. The boat has to return and start properly, or she is scored OCS.
How far back do you have to go if you are over early?
Until your hull is completely on the pre-start side of the starting line or one of its extensions. Then you start again.
What is the difference between an individual and a general recall?
An individual recall (rule 29.1) calls back only the boats that were over, and the race goes on. A general recall (rule 29.2) restarts the whole start.
What happens if an OCS boat does not go back?
She is scored OCS for that race.
Paraphrased from rule 29 of the Racing Rules of Sailing 2025-2028, not quoted. The rule text is World Sailing's, and the rulebook is what a protest hearing reads.