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Part 2 — When Boats Meet

Section C — At Marks And Obstructions

Section C rules do not apply between boats when the mark or obstruction referred to in those rules is a starting mark surrounded by navigable water or its anchor line, from the time the boats are approaching it to start until they have left it astern.

20

ROOM TO TACK AT AN OBSTRUCTION

20.1: Hailing

A boat may hail for room to tack and avoid a boat on the same tack by hailing ‘Room to tack’. However, she shall not hail unless

  • (a) she is approaching an obstruction and will soon need to make a substantial course change to avoid it safely, and
  • (b) she is sailing close-hauled or above. In addition, she shall not hail if the obstruction is a mark and a boat that is fetching it would be required to change course as a result of the hail.

20.2: Responding

  • (a) After a boat hails, she shall give a hailed boat time to respond.
  • (b) A hailed boat shall respond even if the hail breaks rule 20.1.
  • (c) A hailed boat shall respond either by tacking as soon as possible, or by immediately replying ‘You tack’ and then giving the hailing boat room to tack and avoid her.
  • (d) When a hailed boat responds, the hailing boat shall tack as soon as possible.
  • (e) From the time a boat hails until she has tacked and avoided a hailed boat, rule 18.2 does not apply between them.

20.3: Passing On a Hail to an Additional Boat

When a boat has been hailed for room to tack and she intends to respond by tacking, she may hail another boat on the same tack for room to tack and avoid her. She may hail even if her hail does not meet the conditions of rule 20.1. Rule 20.2 applies between her and a boat she hails.

20.4: Additional Requirements for Hails

  • (a) When conditions are such that a hail may not be heard, the boat shall also make a signal that clearly indicates her need for room to tack or her response.
  • (b) The notice of race may specify an alternative communication for a boat to indicate her need for room to tack or her response, and require boats to use it.

Definitions in Context

Fetching

A boat is fetching a mark when she is in a position to pass to windward of it and leave it on the required side without changing tack.

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.

Mark-Room

Room for a boat

  • (a) to sail to the mark when her proper course is to sail close to it,
  • (b) to round or pass the mark on the required side, and
  • (c) to leave it astern.
Obstruction

An obstruction is

  • (a) an object that a boat could not pass without changing course substantially, if she were sailing directly towards it and one of her hull lengths from it;
  • (b) an object that can be safely passed on only one side; or
  • (c) an object, area or line that is so designated in a rule.

However, a boat racing is not an obstruction to other boats unless they are required to keep clear of her or, if rule 22 applies, avoid her.

Room

The space a boat needs in the existing conditions, including space to comply with her obligations under the rules of Part 2 and rule 31, while manoeuvring promptly in a seamanlike way.

Tack, Starboard or Port

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

Related Cases

Case 3

A leeward port-tack boat, hailing for room to tack when faced with an oncoming starboard-tack boat, an obstruction, is not required to anticipate that the windward boat will fail to comply with her obligation to tack promptly or otherwise provide room.

Case 10

If a boat hails ‘Room to tack’ when she is neither approaching an obstruction nor sailing close-hauled or above, she breaks rule 20.1. The hailed boat is required to respond even if the hail breaks rule 20.1.

Case 54

Interpretation of rule 20’s requirements for hails and signals and their timing.

Rule 19

Rule 19 applies between two boats at an obstruction except when rule 18 applies between them and (a) the obstruction is the mark, or (b) the obstruction is anot...

Rule 21

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 kee...

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