Racing Rules of Sailing Summary

Part 2 - When Boats Meet

As presented by US Sailing Judge Tom Roberts at the Islander 36 Rules Seminar April 23, 2005 at Encinal YC.

In the following table, italicized words have specific definitions which are provided below.


Right-of-Way / Give Way Subject


Section A - Right of Way



S - P

Starboard tack over Port tack


L - W

Windward boat keep clear



Boat clear astern keep clear


Tack - Tacking

A boat tacking shall keep clear

Section B - General Limitations



Avoid contact

Everyone's responsibility


Acquiring right of way

Give room to keep clear


Changing course

Give room to keep clear


Proper Course / Luffing


Section C - At Marks & Obstructions



Rounding Marks & Passing Obstructions

Outside boat gives inside boat room if overlapped at the two-length zone or if there is a continuing obstruction


Obstructions - Sea Room

Hailing for room to tack at an obstruction

Section D - Other Rules



Starting Errors, Penalty Turns, Moving Astern

Keep clear


Capsized, Anchored or Aground

Keep clear


Interfering with another boat


Tack, Starboard or Port - A boat is on the tack, starboard or port, corresponding to her windward side.

Leeward and Windward - A boat's leeward side is the side that is or, when she is head to wind, was away from the wind. However, when sailing by the lee or directly downwind, her leeward side is the side on which her mainsail lies. The other side is her windward side. When two boats on the same tack overlap, the one on the leeward side of the other is the leeward boat. The other is the windward boat.

Clear Astern and Clear Ahead; Overlap - One boat is clear astern of another when her hull and equipment in normal position are behind a line abeam from the aftermost point of the other's hull and equipment in normal position. The other boat is clear ahead. They overlap when neither is clear astern. However, they also overlap when a boat between them overlaps both. These terms do not apply to boats on opposite tacks unless rule 18 applies.

Keep Clear - One boat keeps clear of another if the other boat can sail her course with no need to take avoiding action and, when the boats are overlapped on the same tack, if the leeward boat could change course in both directions without immediately making contact with the windward boat.

Room - The space a boat needs in the existing conditions while manoeuvring promptly in a seamanlike way.

Proper Course - A course a boat would sail to finish as soon as possible in the absence of the other boats referred to in the rule using the term. A boat has no proper course before her starting signal.

Obstruction - An object that a boat could not pass without changing course substantially, if she were sailing directly toward it and one of her hull lengths from it. An object that can be safely passed on only one side and an area so designated by the sailing instructions are also obstructions. However, a boat racing is not an obstruction to other boats unless they are required to keep clear of her, give her room or, if Rule 21 applies, avoid her.

Two-Length Zone - The area around a mark or obstruction within a distance of two hull lengths of the boat nearer to it.

Mark - An object the sailing instructions require a boat to leave on a specified side, and a race committee boat surrounded by navigable water from which the starting or finishing line extends. An anchor line and objects attached temporarily or accidentally to a mark are not part of it.