Watching the recent videos of the IOM Worlds in France I noticed that on several occasions when a port tack boat was ducking under a starboard tack boat,on a beat to the windward mark,the starboard boat immediately tacked on to port as the port boat was crossing her stern and subsequently the now windward boat sailed,fell,down on the the leeward boat causing the ducking boat to make further drastic course alterations.

I believe that Rule 16.2 forbids the original starboard boat to interfere with the ducking boat.

Am I right or wrong please?

Another point; if a port tack boat is,say,just crossing ahead of a starboard boat and the starboard boat gets a lifting wind shift can she alter her course but continue to pass astern and validly protest? If the starb'd boat had taken full advantage of the lift she could have collided. I know that she must give the port boat opportunity to keep clear but if the distance ahead is very small isn't the port boat a chancer and must take the consequences of a protest call under Rule 10?

Thanks.

Terry

Hi Terry,

I agree with your first comment. The stbd boat that tacks and causes P to make a further alteration of course breaks R 16.2 and maybe R 13 or R 11. Once S has tacked to port and becomes windward and ROW changes to the old P, R 15 does not apply as the change in ROW was caused by S when she tacked.

In second question, R 16.1 would apply, and S has to give room to P to stay clear as S alters course to take the lift. So while S may always protest, in this case, I think the protest may be dismissed.

John

Thank you John.

Terry

Hi Barry,

That’s a really good question. The quick answer is “no” – When the ROW changes but is caused by the boat that previously had ROW, the new ROW does not have the responsibility to give room - she may continue on her course. But it does not give her a hunting license, eg – she cannot luff sharply, as 16.1 would apply.

R 15 is a ‘momentary’ rule that applies briefly when ROW changes. If you gain ROW by your action, then R 15 says you must do it in such a way that the other boat may keep clear – and they have an obligation to begin to keep clear. If they touch you as they try to keep clear, then you did not give enough room, and break R 15. If they delay and subsequently the boats drift together, then they break the applicable room, eg R 11 W/L. The R 15 protection has that word ‘initially’.

The opposite situation is where the stbd ROW boat tacks to port and to weather of a Port tack, now an overlapped leeward boat. PL does not have to give room under R 15, and if they are so close that new W cannot stay clear, then the boat that tacked probably broke R 13 and also breaks R 11. But once the overlap exists, L may only alter course (eg luff) if she gives room to W to stay clear under R 16.1.

There are no cases that cover this explicitly, but the preamble of several cases (below) provide some guidance.

John

W.S. Case Book.

CASE 27

A boat is not required to anticipate that another boat will break a rule. When a boat acquires right of way as a result of her own actions, the other boat is entitled to room to keep clear.

CASE 93

If a boat luffs immediately after she becomes overlapped to leeward of another boat and there is no seamanlike action that would enable the other boat to keep clear, the boat that luffed breaks rules 15 and 16.1. The other boat breaks rule 11, but is exonerated.

IRSA Case Book

Case B8

A boat that deliberately gives up right-of-way and immediately sails into a position in which she can only avoid contact with one boat by breaking a rule and making contact with another boat resulting in damage is sailing without concern for the consequences of her actions. She does not comply with the basic principle of sportsmanship and the rules.

Hi Barry,

that phrase is part of the whole sentence - all it says it that in that circumstance, she does not have to "initially give room" when she gains ROW.

JOhn

John,

How about making a summary for this

Boat A on Starboard – tacked to Port and to weather of Boat B

Boat B acquires ROW due to the action of Boat A

Therefore

Boat A must keep clear of Boat B – when tacking - given Boat B passed astern of Boat A

Rule 16.2

Rule 13

Assumed that Boat A did not infringe upon Rule 16.2

Boat A must keep clear – once becoming Weather Boat

Rule 15 – Not applicable to Boat B

Rule 11– Applicable to Boat A

Boat B need not give room to Boat A and can luff at any time

Rule 15 – Not applicable to Boat B

Rule 11– Applicable to Boat A

Boat B could have tacked to starboard immediately Boat A looked like tacking?

Do I have it correct?

Yes???

Boat B need not give room to Boat A and can luff at any time

Rule 15 – Not applicable to Boat B

Rule 11– Applicable to Boat A

Boat B could have tacked to starboard immediately Boat A looked like tacking?

Do I have it correct?

Yes???

 

Hi Erick,

Your first two summaries are fine, but these two need a bit of work. My comments are in bold

Boat B need not give room to Boat A and can luff at any time but as she becomes ROW, she has to give room under R 16.1 if she alters course

Rule 15 – Not applicable to Boat B

Rule 11– Applicable to Boat A

Rule 17 does not apply if they became overlapped before A completed her tack.

Boat B could have tacked to starboard immediately Boat A looked like tacking?

As A luffs up to head to wind, she is still on stbd, and not yet subject to R 13, so B must still stay clear under R 10.

Hope this helps,

John

I have some diagrams that cover this type of incident in my article "Chapter 8 Proper Course" on pages 6 and 7. This article covers the situation from the perspective of R 17, but is covers R 15 too.

https://sites.google.com/site/johnsrcsailingrulesandtactics/

John