Racing Rules of Sailing

30.3

U Flag Rule

If flag U has been displayed, no part of a boat’s hull shall be in the triangle formed by the ends of the starting line and the first mark during the last minute before her starting signal. If a boat breaks this rule and is identified, she shall be disqualified without a hearing, but not if the race is restarted or resailed.

Definitions in Context

Mark

An object the sailing instructions require a boat to leave on a specified side, a race committee vessel surrounded by navigable water from which the starting or finishing line extends, and an object intentionally attached to the object or vessel. However, an anchor line is not part of the mark.

Rule

(a) The rules in this book, including the Definitions, Race Signals, Introduction, preambles and the rules of relevant appendices, but not the Basic Principles or titles;
(b) World Sailing Regulations that have been designated by World Sailing as having the status of a rule and are published on the World Sailing website;
(c) the prescriptions of the national authority, unless they are changed by the notice of race or sailing instructions in compliance with the national authority’s prescription, if any, to rule 88.2;
(d) the class rules (for a boat racing under a handicap or rating system, the rules of that system are ‘class rules’);
(e) the notice of race;
(f) the sailing instructions; and
(g) any other documents that govern the event.

Start

A boat starts when, her hull having been entirely on the pre-start side of the starting line at or after her starting signal, and having complied with rule 30.1 if it applies, any part of her hull crosses the starting line from the pre-start side to the course side.