Yacht Racing Rules


This document provides a very basic overview of the official ISAF rules that have been adopted by the MYA. As Hove Lagoon supports the MYA these rules are adopted for all our events. These notes are based on the series of courses presented by Bill Letten (Racing Officer) on Tuesday evenings in 2009. They are presented in a simplified form and only cover the basics when racing with other yachts. These notes are subject to amendment and improvement and any errors or suggested additions are very welcome. For serious inter-club and National competition you will need to know and understand the full ISAF rules instinctively and without thinking. When you break a rule that interferes with another boat you must promptly do a penalty turn, even if nobody challenges. If you touch a course buoy you must also do one penalty turn. Even if you have right of way you must avoid contact at all costs, if you don't and cause damage the penalty is to retire (Rule 44).

Port & Starboard Tack

A boat on Port Tack must keep clear of a boat on a Starboard Tack (Port gives way). To remember which is Port & which is Starboard Tack, select one of the following & remember it:
With wind on boats head, if you go left you are on Starboard, if you go right you are on Port.
Or; If wind is coming over the boats right side, you are on Starboard, if wind is coming over the Left side, you are on Port.
Boat A is on Starboard Tack & therefore has the Right of Way
Boat B is on Port Tack & therefore has to give way,
by either tacking to avoid Boat A or bear-away around the stern of A

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Windward & Leeward

A boat that is windward of other boats must keep clear of Leeward boats. In the following example:
As Boat B Luffs up, Boat A (as the windward boat) must also Luff up to keep clear of Boat B.

Boat A is the Windward boat & must keep clear of Boat B
Boat B is the Leeward boat (On all points of Sailing)

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Overlap on same Tack

Diagram 1
Boats are overlapped when any part of a boat passes a line drawn square across another boats Stern/Transom.
The following Diagram shows two boats on the same Tack & overlapped
Under these circumstances the Windward Boat (Boat A) must keep clear of a Leeward Boat.

Diagram 2
Boat A is overtaking Boat B
Boat A is the Windward Boat and therefore must keep clear of Boat B
Boat B is allowed to Luff-up (to Protect it's wind) and Boat A again must keep clear.

However In the following diagram under Rule 17 - Same Tack, Proper Course

Diagram 3

Boat A is moving faster than Boat B and has just established an overlap from clear astern.
Both boats are on the same Tack and separated by less than two boat lengths.
Although Boat A is the Leeward boat she cannot Luff up while both boats remain on the same tack & overlapped
Boat A can only luff up if she sails astern of Boat B.

Diagram 4
The following diagram shows Boat A and Boat C are overlapped because Boat B is BETWEEN them.
Diagram 5
In the following diagram Boat A and Boat C are NOT OVERLAPPED as Boat B is NOT BETWEEN them.
Also In the following diagram Boat B and Boat C ARE OVERLAPPED

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Start Line Reaching

Usually done when too early for the Start)
Boats 3 2 1 are early at the start ! ! !
As these are Windward boats they must
KEEP CLEAR of boats 4 and 5 that are starting correctly.

This should not be done unless there is clear space and no danger of impeding a boat starting correctly.

Remember you have no right of way:



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Rounding Marks

Around each course Marker Buoy there is a Four Boat length Zone (For One-Metre this will be 4 metres). There is no Zone around the start or finishing Buoys.
The diagram shows the overlap is established outside the 4-boat zone.
An overlap established inside the 4-boat zone is NOT ALLOWED.

Boat B has an overlap on boat A and if maintained at the start of the 4-boat zone, Boat B must be given room by boat A to round the Mark.
(Note these rights are maintained until you exit the 4 boat zone after rounding the mark)

If Boat B is unsure if Boat A will give room, then Boat B should Hail for Water.

If the overlap is broken in the 4-boat zone, Boat A is still liable to give room to Boat B
Boat B cannot claim water round the Mark if the overlap was only gained inside the 4-boat zone.
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Rounding the Windward Mark

(a) The Mark should be treated, when on opposite tacks, as though it was NOT there.
(b) A Starboard Tack boat on the Lay-Line has normal rights in and out of the 4-boat Zone.
(c) A Port Tack boat approaching the Windward Mark must avoid a Starboard Tack boat in the 4-boat Zone.
(d) A Port Tack boat has no rights in the 4-boat Zone.
(e) The Mark should always, where possible, be approached on a Starboard Tack Lay-Line or above.
(f) A Port Tack boat should NOT Lay the Mark.

Diagram 1
Boat A must keep clear of boat B in the 4-boat Zone.
Boat A must either cross the bow of boat B (without causing Boat B to change course), if there is any chance of a possible collision, Boat A MUST bears away under boat B stern.
Boat A Must either Tack or Bear-Away (around Boat B’s stern)
Boat B is the Right of Way Boat

Diagram 2
A Port Tack boat can tack under a Starboard Tack boat, which, as the windward boat, has to keep clear.
A Port Tack boat can Luff (if wind allows) but must give a Starboard Tack boat room to keep clear.

The following manoeuvre outside the 4-boat Zone is legal but cannot be done inside the 4 -boat Zone.
After tacking Boat A can Luff but must allow Boat B to keep clear.

Diagram 3 (all Buoys, except start)
Boat A and B retain their established rights until they are outside the 4-boat zone, therefore:
Boat D has no rights over Boat A or B until they are out of the 4-boat zone
Boat C has no rights over A, B or D & must give way
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Round Mark DirectionIf you round a Mark in the wrong direction you must go back and 'unwind' the string as per the following diagram.

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Obstruction to Sea Room

An obstruction to Sea Room could be a committee boat, a bank, a marker buoy or a boat out of control.

In the following diagram:
Boat B cannot tack without hailing boat A
Boat B must call either ‘WATER’ or ‘ROOM to TACK'
Boat A must respond ‘YOU TACK’ and either go behind boat B or Tacks in response.
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