Rule 18.2 - Giving Mark-Room: Racing Rules of Sailing 2021-2024

Our second installment on mark-room is Rule 18.2 – Giving Mark-Room. We covered Rule 18.1 separately and we’ll update Rules 18.3 and 18.4 in a future post.

In 2018, the Inland Lake Yachting Association (ILYA) and SailZing, LLC partnered on a Fair Sailing initiative. As part of this initiative, SailZing worked with the ILYA and UK Sailmakers to develop a series of articles on the rules. With the rules changes in 2021, SailZing is updating these articles and adding video summaries.

Our thanks to UK Sailmakers for generating the animated scenarios.

Rule 18.2 Video

Rule 18.2 – Giving Mark Room

“(a) When boats are overlapped the outside boat shall give the inside boat mark-room, unless rule 18.2(b) applies.

(b) If boats are overlapped when the first of them reaches the zone, the outside boat at that moment shall thereafter give the inside boat mark-room. If a boat is clear ahead when she reaches the zone, the boat clear astern at that moment shall thereafter give her mark-room.

(1) she shall continue to do so even if later an overlap is broken or a new overlap begins;

(2) if she becomes overlapped inside the boat entitled to mark-room, she shall also give that boat room to sail her proper course while they remain overlapped.

(d) Rules 18.2(b) and (c) cease to apply if the boat entitled to mark-room passes head to wind or leaves the zone.”

(e) If there is reasonable doubt that a boat obtained or broke an overlap in time, it shall be presumed that she did not.

(f) If a boat obtained an inside overlap from clear astern or by tacking to windward of the other boat and, from the time the overlap began, the outside boat has been unable to give mark-room, she is not required to give it.”

Definitions

Mark-Room

Room for a boat to leave the mark on the required side. Also,

(a) room to sail to the mark when her proper course is to sail close to it, and

(b) room to round or pass the mark as necessary to sail the course without touching the mark.

However, mark-room for a boat does not include room to tack unless she is overlapped inside and to windward of the boat required to give mark-room and she would be fetching the mark after her tack. (Example of a situation that requires giving room to tack is shown at right.)

Previously-defined terms (click to refresh your memory): overlap, clear ahead, clear astern, zone, room, proper course

Rule 18.2 Key Points

This rule applies at both the windward and leeward marks. We’ll cover windward mark situations when we cover Rule 18.3.
If Rule 18 applies, then either Rule 18.2(a) or Rule 18.2(b) will apply. The most common situations involve Rule 18.2(b).
The key to understanding Rule 18.2(b) is to think of a “snapshot” when the first boat enters the zone. If the first boat enters the zone clear ahead, she need not give mark room to boats that are clear astern.
When a boat claims she obtained or broke an overlap in time, the claim must be well-supported. If there is reasonable doubt, the claim will not be accepted.
Rule 18 “turns off” when mark-room has been given. This means satisfying all the required portions of the mark-room definition.

Rule 18.2 Change

The 2021 changes modified Rules 18.1 and 18.2 slightly. Rule 18.1 now states that Rule 18 turns off when mark-room has been given. This applies to the entire rule. The corresponding statement in Rule 18.2 was removed. See the markup for Rule 18.2 to the right.

Scenarios

#1 – “Common Leeward Mark, Example 1”

Description: Yellow and Blue are sailing downwind on the same tack.

Should Yellow give mark-room to Blue? Answer

#2 – “Common Leeward Mark, Example 2”

Description: Yellow and Blue are sailing downwind on opposite tacks. When Blue enters the zone, she is clear ahead of Yellow. After entering the zone, Yellow becomes overlapped with Blue.

Should Blue give mark-room to Yellow? Answer

#3 – “Common Leeward Mark, Example 3”

Description: Yellow and Blue are sailing downwind on opposite tacks with spinnakers. Yellow reaches the mark first and does not give Blue mark-room. Blue heads up to avoid Yellow. There was no contact.

Should Yellow give mark-room to Blue? Answer

#4 – “Common Leeward Mark, Example 4”

Description: Yellow and Blue are sailing downwind on opposite tacks. Shortly after Yellow reaches the zone, Blue hails for room. Yellow does not respond verbally until reaching the mark, and then hails “no room.” Yellow does not give Blue mark room. Blue protests Yellow. Yellow alleges that she broke the overlap before she entered the zone. There was no contact.

Should Yellow give mark-room to Blue? Answer

Would a protest committee be likely to accept Yellow’s claim that she broke the overlap just before reaching the zone? Answer

#5 – “Common Leeward Mark, Example 5”

Description: Yellow and Blue are sailing downwind to the leeward gate on the same tack. After entering the zone, Blue turns up, sails faster, and breaks the overlap.

Should Blue give mark-room to Yellow? Answer

#6 – “Common Leeward Mark, Example 6”

Description: Yellow and Blue are sailing to the leeward mark. Blue is clear ahead when reaching the zone. Blue sails wide of the mark due to trouble with the spinnaker takedown. Yellow sails inside of Blue around the mark.

Is Yellow within her rights to round the mark inside Blue? Answer

#7 – “Common Leeward Mark, Example 7”

Description: Yellow, Blue, and Green are approaching the leeward mark. After entering the zone, Green slows down, but Blue speeds up and rounds inside of Yellow. Assume that Blue did not touch the mark. Yellow heads up and contacts Blue. There was no damage.

Which boat should promptly take a penalty? Answer

#8 – “Complex Leeward Mark”

Description: Multiple boats are approaching the leeward mark. Watch the scenario several times.

Is Yellow entitled to mark-room from Light Blue? Answer

Is Magenta entitled to mark-room from Green? Answer

When does Rule 18.2(a) Apply?

We’ve covered the most common rule 18.2 scenarios, which are usually related to Rule 18.2(b) and the three boat length zone. So when does Rule 18.2a apply? Here are two examples.

On a beat to windward, recall that, in accordance with Rule 18.1, Rule 18 does not apply between boats on opposite tacks. If two boats are already in the zone, on opposite tacks, and then one of them tacks, Rule 18 begins to apply, In this situation, Rule 18.2(a) kicks in. In the example shown, once Yellow tacks to port, Blue is the inside boat and is overlapped, so Blue is entitled to mark room from yellow.

Here’s a leeward mark example, from Case 59 in the casebook. Blue is forced to sail outside the zone, due to the presence of the grey boats. Yellow is clear astern of Blue but enters the zone before Blue. Read Rule 18.2(b) carefully to see that it doesn’t apply here. Instead, Rule 18.2(a) begins to apply when Blue and Yellow are overlapped at position 2. Thus, Blue must give mark-room to Yellow.

World Sailing Cases of Interest

25 – When an inside overlapped windward boat that is entitled to mark-room takes more space than she is entitled to, she must keep clear of the outside leeward boat and the outside boat may luff provided she gives the inside boat room to keep clear.

59 – A boat abreast of a mark but outside the zone. Illustrates an application of Rule 18.2(a).

63 – At a mark, when space is available to a boat that is not entitled to it, she may, at her own risk, take advantage of the space.

70 – an inside overlapped windward boat that is entitled to mark-room from the outside boat must keep clear of thee outside boat and, if she is sailing outside of the mark-room to which she is entitled, she is not exonerated if she fails to keep clear.

75 – When an inside overlapped right-of-way boat must gybe at a mark, she is entitled to sail her proper course until she gybes.