Rules of the Road

Port: If a power-driven vessel approaches within this sector, maintain your course and speed with caution.

Starboard: If any vessel approaches within this sector, keep out of its way (Note: This rule may not always apply if one or both vessels are sailboats.)

Stern: If any vessel approaches this sector, maintain your course and speed with caution.

A blows one blast and alters course to starboard.

B blows one blast and alters course to starboard

A keeps clear of and must avoid crossing ahead of B.

Any vessel overtaking another must keep clear.

A keeps clear of B; C keeps clear of A and B

B keeps clear of D; D keeps clear of A and C

A power-driven vessel keeps clear of a sailing vessel.

When each sailing vessel has the wind on a different side, the vessel that has the wind on its port (left) side shall keep out of the way of the other. In our illustration, A keeps clear of B.

If a sailing vessel has the wind on its port side and the sailor cannot determine with certainty whether the other vessel has the wind on its port or starboard side, the first vessel must keep out of the way of the other.

When both sailing vessels have the wind on the same side, the vessel to windward shall keep out of the way of the vessel to leeward. B keeps clear of A.

Note: The windward side is defined as the side opposite to that of which the mainsail is carried or, in the case of a square-rigged vessel, the side opposite to that on which the largest for-and-aft sail is carried.