Section D
Other Rules
When rule 21 or 22 applies between two boats, Section A rules do not.

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21  Starting Errors; Taking Penalties; Moving Astern
21.1  A boat sailing towards the pre-start side of the starting line or one of its extensions after her starting signal to start or to comply with rule 30.1 shall keep clear of a boat not doing so until she is completely on the pre-start side.
21.2  A boat taking a penalty shall keep clear of one that is not.
21.3  A boat moving astern by backing a sail shall keep clear of one that is not.

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22  Capsized, Anchored or Aground; Rescuing
If possible, a boat shall avoid a boat that is capsized or has not regained control after capsizing, is anchored or aground, or is trying to help a person or vessel in danger. A boat is capsized when her masthead is in the water.

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23   Interfering with Another Boat
23.1  If reasonably possible, a boat not racing shall not interfere with a boat that is racing.
23.2 Except when sailing her proper course, a boat shall not interfere with a boat taking a penalty or sailing on another leg.

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Definitions
Fundamental Rules
Part 2A - Right of Way
Part 2B - General Limitations
Part 2C - At Marks and Obstructions
Part 3- Conduct of a Race
Part 4 - Other Requirements When Racing
Part 5A - Protests
Part 5B - Hearings and Decisions
Part 5C - Gross Misconduct
Part 5D - Appeals