The notice of race shall be made available to each boat that enters an event before she enters. The sailing instructions shall be made available to each boat before a race begins.
 

The meanings of the visual and sound signals stated in Race Signals shall not be changed except under rule 86.1(b).  The meanings of any other signals that may be used shall be stated in the notice of race or sailing instructions.

Races shall be started by using the following signals. Times shall be taken from the visual signals; the absence of a sound signal shall be disregarded.

  Minutes before                Visual Signal                        Sound             Means
   starting signal                                                              Signal

           5*                             Class flag                                One               Warning signal
           4                 P, I, Z, Z with I, U, or black flag           One               Preparatory signal
           1                   Preparatory flag removed               One long           One minute
           0                        Class flag removed                       One                Starting signal
 * or as stated in the notice of race or sailing instructions

The warning signal for each succeeding class shall be made with or after the starting signal of the preceding class.

 Before the starting signal, the race committee may for any reason postpone (display flag AP, AP over H, or AP over A, with two sounds) or abandon the race (display flag N, N over H, or N over A, with three sounds) 

  

A boat shall sail the course. 
 

A boat may correct any errors in sailing the course, provided she has not finished. 

When at a boat's starting signal any part of her hull is on the course side of the starting line or she must comply with rule 30.1, the race committee shall promptly display flag X with one sound.  The flag shall be displayed until the hull of each such boat has been completely on the pre-start side of the of the starting line or one of its extensions and until all such boats have complied with rule 30.1 if it applies, but no later than four minutes after the starting signal or one minute before any later starting signal, whichever is earlier. If rule 29.2, 30.3 or 30.4 applies this rule does not.
 

If flag I has been displayed, and any part of a boat's hull is on the course side of the starting line or one of its extensions during the last minute before her starting signal, she shall sail across an extension so that her hull is completely on the pre-start side before she starts.
 

If flag Z 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 receive, without a hearing, a 20% Scoring Penalty calculated as stated in rule 44.3(c). She shall be penalized even if the race is restarted or re-sailed, but not if it is postponed or abandoned before the starting signal. If she is similarly identified during a subsequent attempt to start the same race, she shall receive an additional 20% Scoring Penalty. 

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. 
 

If a black flag 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, even if the race is restarted or resailed, but not if it is postponed or abandoned before the starting signal. If a general recall is signaled or the race is abandoned after the starting signal, the race committee shall display her sail number before the next warning signal for that race, and if the race is restarted or resailed she shall not sail in it. If she does so, her disqualification shall not be excluded in calculating her series score. 
 

While racing, a boat shall not touch a starting mark before starting, a mark that begins, bounds or ends the leg of the course on which she is sailing, or a finishing mark after finishing.
 

 

After the starting signal, the race committee may shorten the course or abandon the race:

In addition, the race committee may shorten the course so that other scheduled races can be sailed, or abandon the race because of an error in the starting procedure. However, after one boat has sailed the course within the race time limit, if any, the race committee shall not abandon the race without considering the consequences for all boats in the race or series. 

To shorten the course, the race committee shall display flag S with two sounds before the first boat crosses the the finishing line. If the course is shortened, the finishing line shall be,

To abandon a race in progress, the race committee shall display flag N, N over H, or N over A, with three sounds.

While boats are racing, the race committee may change a leg of the course that begins at a rounding mark or at a gate by changing the position of the next mark (or the finishing line) and signalling all boats before they begin the leg. The next mark need not be in position at that time.

 

If a mark is missing or out of position while boats are racing, the race committee shall, if possible,

 

If one boat sails the course within the time limit for that race, if any, all boats that finish shall be scored according to their finishing places unless the race is abandoned. If no boat sails the course within the race time limit, the race committee shall abandon the race.

If a race is restarted or re-sailed, a breach of a rule in the original race, or in any previous restart or resail of that race shall not

When the race committee displays flag V with one sound, all boats and official and support vessels shall, if possible, monitor the race committee communication channel for search and rescue instructions