Well, photographic evidence is always suspect, because it can be difficult to judge distances due to perspective. That said, however, this video angle is pretty good.

It looks to me like the Hobie 16 gybes about 4-5 boatlengths from the mark (outside the zone), but I'll do the rule analysis both ways. If she gybed outside the zone, then:

• At times 0:25-0:41 the H16 is overlapped with 5 boats (purple spin, 2 non-spins, red spin, and blue spin). H16 is on starboard tack, the others are all on port tack. All 5 must keep clear of H16 (rule 10) and they do.
• At time 0:42, H16 gybes. Now rule 11 applies. H16 must keep clear of the boats to leeward, and she does. Purple is either overlapped to windward of H16 or very quickly becomes so. She must keep clear, and she does. All 6 boats sail together until time 0:44.
• At time 0:44, purple (the boat closest to the mark) reaches the zone. Per rule 18.2(b), all the other boats must thereafter give her mark-room. Per rule 18.2(b), all the boats outside H16 must thereafter give her mark-room.
• At times 0:44-0:59, the boats sail to the mark. Purple (due to a slow takedown and/or a wave) sails wide of the mark. H16 pulls between Purple and the mark. The other boats give them mark-room (although they don't all keep clear of each other).
• At times 0:59-1:02, H16 and Purple round the mark. During that time, H16 has given Purple mark-room and has kept clear of her. Purple never shut the door on H16.

H16 did not break any rule. Now let's consider the rules if H16 were within 48 feet of the mark when she gybed:

• At times 0:25-0:41, H16 is overlapped with the other boats and has right-of-way under rule 10. Per rule 18.2(b), all other boats must thereafter give H16 mark-room. When in the zone, rule 18.4 requires H16 sail no further than necessary to sail her proper course before gybing.
• At time 0:42, H16 gybes, satisfying rule 18.4.
• After time 0:42, H16 takes the mark-room to which she is entitled.

Again, H16 breaks no rule.

It appears to me that the Nacra and the Prindle (the non-spins) might both break rule 11 at time 0:59. The Prindle would be exonerated under rule 64.1(a).

The boat that really does well, is the one with the smoke-color round-top mainsail. She comes from behind and shoots through the hole right behind the H16. Poor Red has a bad douse followed by a bad tack and falls behind.

Those who might object to H16 and Round-top taking room to which they are not entitled, I refer to ISAF Case 63, which states "at a mark, when space is made available to a boat that is not entitled to it, she may, at her own risk, take advantage of the space".

Regards,
Eric
US Sailing Certified Judge
Chair, SAYRA Appeals Committee