Right of way with three or more boats

I have "the rules in practice" book which is an excellent guide with lots of examples of boat-on-boat rights of way.   But it's not so hot on tangles involving three or more boats.

Who can answer the following two (for example)

1.  Start line

Boat A is on the start line as the gun goes and boats B & C slot into the gap between boat A and the committee boat.  As the gun goes, Boat A luffs sharply forcing B to luff to avoid a collision.  Boat B calls to boat C who can't luff because he's trapped between B and the comittee boat.  All three boats knock hulls.

Boat A is in the right and sails off - but what about B & C?  Should they both do turns?  Who's to blame for the collision?

2.  Room to tack

A, B and C are on starboard beating towards the shore with A closest to the bank.  Boat A calls for water and tacks to port,  B has to tack to port to avoid being hit by A.  C stands-on, calling "starboard" to B on the basis that B can either sit head to wind until C has passed or B can duck C.

Is boat C in his rights to stay on starboard?  At what point can boat C fairly expect A & B to tack back onto Starboard, heading back towards the bank?

Why is boat A luffing? Once the gun goes it no longer has the right to luff to head to wind, as there is now a proper course, so it can't luff above its chosen upwind sailing angle, Boat A is in the wrong if i have interpreted the question correctly

Originally posted by NickA 1.  Start line Boat A is on the start line as the gun goes and boats B & C slot into the gap between boat A and the committee boat.  As the gun goes, Boat A luffs sharply forcing B to luff to avoid a collision.  Boat B calls to boat C who can't luff because he's trapped between B and the comittee boat.  All three boats knock hulls. Boat A is in the right and sails off - but what about B & C?  Should they both do turns?  Who's to blame for the collision?

You can generally get through complicated situations by applying the rules 'pairwise' between boats.

Where B cannot respond because of the presence of C and C cannot respond becaues of the RC Boat, then A, changing course, has not given B room to keep clear and breaks rule 16.1.  A, having nothing to leeward to prevent her from bearing away to avoid contact also breaks rule 14, but might be protected from penalty if there is no injury or damage under rule 14(b).

B does not keep clear of A.  B breaks rule 11.  B, changing course has not given C room to keep clear and breaks rule 16.1.  B is compelled to break rules 11 and 16.1 because of A breaking rule 16.1.  B should be exonerated under rule 64.1(c).  Because she is compelled by A, it is not reasonably possible for B to avoid contact with A or C and B does not break rule 14.

C does not keep clear of B.  C breaks rule 11.  C is compelled ot break rule 11 because of B breaking rule 16.1.  C should be exonerated under rule 64.1(c).  Because she is compelled by B, it is not reasonably possible for C to avoid contact with B and C does not break rule 14.

The scenario has B and C becoming overlapped on A from CASTN to windward of A.  Rule 17 and proper course do not apply.

 

Originally posted by NickA 2.  Room to tack A, B and C are on starboard beating towards the shore with A closest to the bank.  Boat A calls for water and tacks to port,  B has to tack to port to avoid being hit by A.  C stands-on, calling "starboard" to B on the basis that B can either sit head to wind until C has passed or B can duck C. Is boat C in his rights to stay on starboard?  At what point can boat C fairly expect A & B to tack back onto Starboard, heading back towards the bank?

If A hails and tacks simultaneously, she has not given B time to respond and
A breaks rule 20.1(a).

If C is so close to A and B that C will have to respond before A is able to tack, then C is a 'hailed boat' and must respond in accordance with rule 20 (Case 113).

If, on the other hand, C is a little more separated from A and B, so that it is NOT necessary for C to respond before A is able to tack, then C is NOT a 'hailed boat' and owes no obligation under rule 20.

Under rule  20, B is required to tack or give A room to tack and avoid her:  in neither case is she required to keep clear of A, thus, A, tacking, is NOT an obstruction to B, and B has no entitlement to hail C under rule 20, unless safety requires B herself to make a substantial course change to avoid the shore.

Generally, a boat having responded to a rule 20 hail by hailing 'You tack', and giving room to tack, may then stand on and force the hailing boat to tack again (Case 101).

Edited by Brass

Originally posted by Brass Originally posted by asterix for your second question - see ISAF Case 113 in the 2010 Supplement to The Case Book for 2009 – 2012. http://www.sailing.org/tools/documents/2010SupplementCaseB-[8260].pdf For goodness sake, guys, use the up to date Case Book that ISAF provides: http://www.sailing.org/tools/documents/CaseBook20092012with2 010changes-[8229].pdf

the two descriptions of case 113 are identical - arn't they?