Rule 19.2(c) "at the moment the overlap begins, there is not room"
While boats are passing a continuing obstruction, if a boat that was clear astern and required to keep clear becomes overlapped between the other boat and the obstruction and, at the moment the overlap begins, there is not room for her to pass between them, she is not entitled to room under rule 19.2(b). While the boats remain overlapped, she shall keep clear and rules 10 and 11 do not apply.
Created: 17-Nov-09 05:20
Two boats are sailing downwind between an island (0.4km x0.4km) and a series of steel mooring pylons extending from the island that are together a continuing obstruction (able to be seen in satellite view near the coordinates below) and a shore. The wind is blowing parallel to the shore. The boats are sailing both on starboard tack with booms out at about 75 degrees from the centreline with wind coming from over the starboard rear quarter. They are headed towards the island as they are sailing the angles downwind rather than straight down the channel on a 180 degree to the wind run, but are 500m away from the shallows around the island. If the bigger, deeper draft, faster boat clear astern overlaps on the island (starboard) side of the slower boat 450m from the island but the wind drops a lot and the bigger boat cannot get past before the bigger boat gets to it's shallows (ie the deeper draft prevents it from going in as close as the smaller boat), does the bigger boat have any rights? Does it matter that at the time the bigger boat established its overlap and given the wind strength at that time, the bigger boat would have easily got in front of the smaller boat and gybed and crossed in front of it before reaching the shallows? Does it matter that if, at the time the overlap commenced, an extension was drawn along each boat's keel through the bow and to the island, both extensions would have hit the island (ie both boats would, if they held their course, have hit the island eventually, albeit at different times and places and depths. (-33.853414, 151.164230 and the boats are headed NNW towards Spectacle island, coming from near Drummoyne Sailing Club.)
If (at -33.850410, 151.163036) as the island begins the boats are sailing NW directly down the channel parallel to the shore on starboard and the front boat sees the boat clear astern approaching to overtake to windward/starboard and heads up so that it is now pointing to the island and the bigger boat still tries to overtake and then establishes an overlap but then is caught out by decreasing depth so it doesn't get past before getting to the edge of unsafe shallow water does it have any rights? In this case the overlap was established while extensions of the keel line of both boats pointed at the island.
What if the overlap was established while both boats were on course to sail past the island but the leeward boat afterwards began luffing the windward boat up towards the island? In this case extensions of the keel line at the time the overlap was established would both have missed the island. (I think in this case there was room and the leeward boat has to stop luffing and give room)
These situations occur in club racing of 3 clubs that sail in these waters.