Friday, 26 September 2008

RRS 18 ON and OFF in RRS 2009-2012

When rule 18 begins to apply

The old rule 18 began to apply when boats were “about to round or pass” That was sometimes at a different moment and place then at the moment when the lock-in/ lock-out provision of rule 18.2(b) and (c) began to apply. (when the closest boat reached the zone)
You could be outside the two length zone and were already busy with your spinnaker, still not sure if you were going to round the mark as inside boat or that the overlap would be broken before the zone was reached and you would need to keep clear, as clear astern boat.

That has been changed in the new rule 18. The moment you enter the zone rule 18 begins to apply and also the lock-in/lock-out provisions of the new rules 18.2(b) and (c) begin to apply.

The “about to round” provision in the old rule had one advantage. It could be argued that the rule began to apply further from the mark with for instance fast boats, strong wind or strong favourable current. You had protection within the context of that rule when you had already an inside overlap outside he zone. That is no longer the case. Rule 18 never ‘switches’ on outside the zone.

However, the obligation of an outside boat under the new rules 18.2(b) begins to apply at the moment one of the boats enters the zone. If before that, the boats had been overlapped for some time, the outside boat had better sail a course that will be in compliance with 18.2(b) the moment she reaches the zone. If after that, the inside boat is not able to sail to the mark in a seamanlike way, the outside boat risks breaking rule 18.2(b).

So, you do need to anticipate what rule 18 will say before you reach the zone. You can’t wait until you are in the zone and then begin to start complying. With he exact moment the rule takes effect now written in the rule, comes the responsibility to comply with that rule at that very moment.

When rule 18 ceases to apply

There is no longer a sentence in the rule which states when rule 18 ceases to apply. That was in the old rule when boats ‘have passed’ the mark. The principal obligation in the new rule is to give mark room until it is no longer needed.

Rule 18.2(c) does give two specific conditions under which rule 18.2(b) ceases to apply:
- if either boat passes head to wind or
- if the boat entitled to mark room leaves the zone.
Both conditions can happen before the need for mark room has ended.


  1. Regarding when 18 ceases to apply:

    Bear in mind the definition of Mark Room. "Room for a boat to sail to the mark, and then room to sail her proper course while at the mark..."

    So, while the inside boat may be entitled to mark room until she leaves the zone, mark room doesn't entitle her to anything after she is no longer "at the mark".

    From the time an inside (or clear-ahead) boat leaves the mark until she leaves the zone, rule 18 applies but it doesn't restrict the actions of the other boat. A subtle, and probably irrelevant distinction in practical terms.

  2. What is missed here, and still not answered to any satisfaction that I can see, is when 18 ceases to apply formally. When a boat is burdened by RRS 18 and is altering course to round, the obligations of RRS 16.1 do not apply. At the point RRS 18 "turns off" any course change by the Right of Way boat is now subject to rule 16.1.

    So, when a leading boat in a match race rounds a leeward mark to starboard and tacks immediately around the mark, the trailing boat (still sailing to the mark) has no 16.1 protection until the leading boat has completed their rounding. What point has that happened? The rules still do not tell us.

  3. Thank you Jos for the explanation on the "RRS 18 ON and OFF in RRS 2009-2012". Did you spot already a workshop on this new rule, like the Rule_18_workshop 2.ppt
    Jan Visser

  4. Thank you for your explanation of the "RRS 18 ON and OFF in RRS 2009-2012". Your explanation is very useful in understanding the new rule 18.
    I welcome New rule which becomes easier than Old rule.
    But I have to prepare to take a thorny path which is to revise my private edition of rules guide book .....
    Sen Yamaoka

  5. Jos,

    Thank you for your explanation. At first I disagreed with part of it which forced me to read the new rules again and recognized a subtlety that I had not noticed before. "you stated sail to the mark in a seamanlike way" which exactly matches the new definition of "Mark-room" which says "Room" (therefore seamanlike way) "for a boat to sail to the mark, and then room to sail her proper course while at the mark."
    Which then begs the question of when does "at the mark" begin so the rights change from seamanlike room to proper course room.

  6. To all, I will prepare a post about the use of the wording "to" and "at" the mark.

    To Greg K: In my opinion rule 16.1 never switches on as long as the boat is sailing her proper course while rounding the mark. This is already much better then in the old rules. Proper course can much more easily be determined then "when both have passed the mark"
    It is now no longer depending on the trailing boat.

    To Jan Visser: there's not yet a workshop PPT on the new rules.


Related Posts Plugin for WordPress, Blogger...