This post has been updated for the 2025-2028 Racing Rules of Sailing.
Rule 42, Propulsion, covers the permitted and non-permitted ways to change your boat’s speed while racing.
In this post we bring together the rule, World Sailing’s official Interpretations of Rule 42, Propulsion (World Sailing, May 2021), a relevant World Sailing case and video examples. Rule 42 is unchanged for 2025-2028.
Because Rule 42 is complex, we present it in two parts. Rule 42 – Propulsion: Part 1 of 2 covers the interpreted terms, Rule 42.1 (basic rule) and Rule 42.2 (prohibited actions). This post covers Rule 42.3 (exceptions).
Video examples: clips from “Rule 42: Finn Class Common Breaches” (TheFinnChannel) and “Top 5 Rule 42 Mistakes” (Dinghy Racing Channel). Each clip starts at the relevant moment.
Rule 42.3 – Exceptions
Labels in capitals (such as ROCK 6) are from World Sailing’s interpretations.
Rolling to Facilitate Steering – Rule 42.3(a)
(a) A boat may be rolled to facilitate steering.
World Sailing, Racing Rules of Sailing 2025-2028 (Study Version), rule 42. Read it online at racingrulesofsailing.org.
- ROCK 6 Heeling to windward to facilitate bearing away and heeling to leeward to facilitate heading up are permitted. The heeling of the boat has to be consistent with the boat’s turn.
- ROCK 7 Repeated rolling not linked to wave patterns is rocking prohibited by rule 42.2(b), even if the boat changes course with each roll.
Video Example
Rolling Through a Tack or Gybe – Rule 42.3(b)
(b) A boat’s crew may move their bodies to exaggerate the rolling that facilitates steering the boat through a tack or a gybe, provided that, just after the tack or gybe is completed, the boat’s speed is not greater than it would have been in the absence of the tack or gybe.
World Sailing, Racing Rules of Sailing 2025-2028 (Study Version), rule 42. Read it online at racingrulesofsailing.org.
- ROCK 8 Body movements that exaggerate rolling and cause a boat to sail out of a tack or a gybe at the same speed as she had just before the manoeuvre are permitted.
- ROCK 9 It is permitted to move the mast to windward of vertical at the completion of a tack or a gybe.
- BASIC 6 After a tack when a boat is on her new close-hauled course, body movement clearly propelling the boat is prohibited under rule 42.1.
- BASIC 7 When the speed of a boat clearly drops after she accelerates out of a tack or a gybe, and there is no obvious change of wind speed or direction, the exception in rule 42.3(b) does not apply and the boat breaks rule 42.1.
Video Example
Pumping to Initiate Surfing, Planing or Foiling – Rule 42.3(c)
(c) When surfing (rapidly accelerating down the front of a wave), planing or foiling is possible,
World Sailing, Racing Rules of Sailing 2025-2028 (Study Version), rule 42. Read it online at racingrulesofsailing.org.
(1) to initiate surfing or planing, each sail may be pulled in only once for each wave or gust of wind, or
(2) to initiate foiling, each sail may be pulled in any number of times.
Note: the words “Except on a beat to windward” from older versions of this rule are no longer in it.
- PUMP 7 A pull of any sail made to attempt to surf or plane when surfing or planing conditions are marginal is permitted even if the attempt is not successful.
- PUMP 8 If a boat repeats an unsuccessful attempt to plane or surf, she is in the yellow light area. A third consecutive unsuccessful attempt is prohibited.
- PUMP 9 Each sail may be pulled at a different time, but only as permitted by rule 42.3(c)(1).
- PUMP 10 It is only necessary for surfing or planing conditions to exist at the position of a boat for her to be permitted to pull in the sail.
- PUMP 11 Surfing or planing may be possible for some boats but not for others. This can be caused, for example, by local gusts or by waves from a motorboat. Also, lighter crews may be able surf or plane when heavier crews cannot.
- PUMP 12 The exception in rule 42.3(c)(1) does not apply to a boat that is already surfing or planing.
Video Example
Sculling – Rule 42.3(d)
(d) When a boat is above a close-hauled course and either stationary or moving slowly, she may scull to turn to a close-hauled course.
World Sailing, Racing Rules of Sailing 2025-2028 (Study Version), rule 42. Read it online at racingrulesofsailing.org.
- SCULL 1 Provided the boat’s course is above close-hauled and she clearly changes direction towards a close-hauled course, repeated forceful movements of the helm are permitted until the boat is on a close-hauled course. This action is permitted even if the boat gains speed. She may scull to turn to a close-hauled course on either tack.
- SCULL 2 After a boat has sculled in one direction, further connected sculling to offset the first sculling action is prohibited.
- SCULL 3 Sculling to offset steering of the boat caused by backing a sail is prohibited.
- Case 8: “Repeated helm movements to position a boat to gain speed on each of a series of waves generated by a passing vessel are not sculling unless they are forceful, and the increase in speed is the result of a permitted use of the water to increase speed.”
Video Examples
Other Exceptions – Rule 42.3(e)-(i)
(e) If a batten is inverted, the boat’s crew may pump the sail until the batten is no longer inverted. This action is not permitted if it clearly propels the boat.
World Sailing, Racing Rules of Sailing 2025-2028 (Study Version), rule 42. Read it online at racingrulesofsailing.org.
(f) A boat may reduce speed by repeatedly moving her helm.
(g) Any means of propulsion may be used to help a person or another vessel in danger.
(h) To get clear after grounding or colliding with a vessel or object, a boat may use force applied by her crew or the crew of the other vessel and any equipment other than a propulsion engine. However, the use of an engine may be permitted by rule 42.3(i).
(i) Sailing instructions may, in stated circumstances, permit propulsion using an engine or any other method, provided the boat does not gain a significant advantage in the race.
Source: Interpretations of Rule 42, Propulsion (World Sailing, May 2021). These interpretations are still the current ones for 2025-2028; the 2025 rule book says “Interpretations of rule 42 are available on the World Sailing website.”
Summary
The exceptions are narrow. You may roll to steer, roll-tack or roll-gybe as long as you come out no faster, pump once per wave or gust to start surfing or planing, and scull only to turn to close-hauled when you’re stopped or moving slowly above close-hauled.
Sources and Resources
- Rule 42 – Propulsion: Part 1 of 2
- Interpretations of Rule 42, Propulsion (World Sailing, May 2021) – the official interpretations quoted in this post
- Racing Rules of Sailing 2025-2028, Part 4 – rule 42 text, racingrulesofsailing.org
- World Sailing Judges Manual – racingrulesofsailing.org
- Video – Common Breaches of Rule 42 (Finn Class) – Sailing Scuttlebutt
- Video – Top 5 Rule 42 Mistakes and How to Avoid Them in Single-Handed Dinghy Racing – Sail-World
- Guidelines for On-the-Water Rule 42 Enforcement at ICSA Events – ICSA
