CASE 16        

Rule 18.2(c), Rounding and Passing Marks and Obstructions: Giving Room; Keeping Clear: Not Overlapped at the Zone
Rule 18.5, Rounding and Passing Marks and Obstructions: Passing a Continuing Obstruction
Definitions, Room

When a boat clear astern overtakes two overlapping boats clear ahead, she may intervene between them only if there is room to pass between them.

Summary of the Facts
Three port-tack boats are on a run. Boats W and L run into a soft patch of wind. M comes roaring up in a vicious little squall and overlaps W. There is room for M to poke her bow between W and L without making contact, but not room to sail through unless W and M trim their mainsheets.

Question
May M establish an overlap between W and L and be entitled to room?

Answer
No. According to the last sentence of the definition Obstruction, L is an obstruction to M and W. Because L is moving in the same direction as and at a speed similar tNo. According to the last sentence of the definition Obstruction, L is an obstruction to M and W. Because L is moving in the same direction as and at a speed similar to that of the other boats, she is a continuing obstruction. Because M is rapidly overtaking the boats clear ahead, the time at which she establishes an overlap on W will be almost the same as the time at which she establishes an overlap on L. While M is clear astern of W and L, she is required by rules 12 and 18.2(c) to keep clear of W and by rule 12 to keep clear of L. According to rule 18.5, if M obtains an overlap to leeward of W she is entitled to room to pass between W and L only if at the moment the overlap begins there is room (in the defined sense of ‘room’) for her to pass between them. As the facts and the diagram indicate, there is not enough space for her to sail between the boats in a seamanlike way (that is, with her boom and spinnaker trimmed appropriately to the wind). Hence, according to rule 18.5’s last sentence, M is not entitled to room to pass between W and L and she must keep clear of W. In addition, if she were to establish an overlap on L, rule 11 would require her to keep clear of L.

RYA 1966/9