Rule 18.1 is a rule that states when rule 18 applies and then list some scenarios where Rule 18 expressly does not applies.
Prior to this, Section C also offers us some information where all of Section C does not apply and should therefore be read in conjunction with Rule 18.1. Here is what Section C says about all rules within it…
Section C rules do not apply at a starting mark surrounded by navigable water or at its anchor line from the time boats are approaching them to start until they have passed them.
Rule 18.1 then gets into specifics. It states:
18.1 When Rule 18 Applies
Rule 18 applies between boats when they are required to leave a mark on the same side and at least one of them is in the zone. However, it does not apply
(a) between boats on opposite tacks on a beat to windward,
(b) between boats on opposite tacks when the proper course at the mark for one but not both of them is to tack,
(c) between a boat approaching a mark and one leaving it, or
(d) if the mark is a continuing obstruction, in which case rule 19 applies.
Rule 18 no longer applies between boats when mark-room has been given.
Let’s have a look at what that looks like in practice…
YES, Rule 18 does apply
You may have said "no" because they are on opposite tacks but Rule 18.1(a) between boats on opposite tacks, on a beat to windward, only applies to windward marks. As none of the other exceptions under Rule 18.1 apply, Rule 18 applies...
NO, Rule 18 does not apply
Land is a continuing obstruction. Unlike "obstruction, "continuing obstruction" is not defined in the rules, so we must take the ordinary meaning of the word. That is "continuing" as in "permanent".
Scenario 5
Green and blue are sailing towards the start line. Blue is in the zone and yellow is overlapped. Both boats are on the same tack and close hauling towards the mark which they both have to leave on port.
YES, Rule 18 does not apply
The fact that green is a long way away does not matter. It stands to reason that green will approach the mark much faster whilst carrying more sail than blue so it pays for blue to be vigilant because Rule 18 kicked in as soon as blue entered the zone...
YES, Rule 18 does apply
It is also possible that the blue boat will need to tack because of the strong currents which will have both boats eventually on the same port tack before both boats need to tack back to a starboard tack before rounding the mark.
So to sum up Rule 18.1…
- It determines if Rule 18 applies – nothing more.
- It applies between boats when:
It does not apply between boats:
between boats on opposite tacks when the proper course at the mark for one but not both of them is to tack, or
between a boat approaching a mark and one leaving it, or
if the mark is a continuing obstruction, in which case rule 19 applies.
- Also, Section C rules (including Rule 18) do not apply at a starting mark surrounded by navigable water.
