CALL UMP 6              

Question 1 Before the start Yellow and Blue, reaching on starboard tack, approach an anchored boat. When Yellow reaches the two-length zone, she is clear ahead of Blue. Yellow passes to windward of it, bears away alongside it, then gybes in order to sail around its stern. Very soon after Yellow gybes, Blue is still on starboard and gains a small inside overlap. Blue changes course trying to avoid contact with Yellow but there is contact. There is a protest. What should the call be? Answer 1 Rule 18.2(c) requires Blue to keep clear until the boats have passed the obstruction, and she is not entitled to room to pass the obstruction if she becomes overlapped inside Yellow. When Yellow changes course and gybes towards the obstruction, she is subject to rule 16.1 (See Answer in CALL UMP 27), and must give Blue room to keep clear. Blue is able to keep clear by luffing but chooses not to, so breaks rule 18.2(c). Penalize Blue..

Question 2
How far beyond the obstruction may Yellow sail before gybing and still rely on 18.2(c)?

Answer 2
When the entire obstruction is astern of both boats, rule 18 ceases to apply and Yellow may no longer rely on rule 18.2(c) to give her right of way over Blue. (See also Answer 2 in CALL UMP 22.)

Question 3 If while keeping clear Blue gains the inside overlap within the two-length zone, and is sailing a course parallel to Yellow’s, before Yellow changes course and gybes, and if Blue is then unable to keep clear, what should the call be? Answer 3 Blue must keep clear of Yellow under rule 18.2(c) until both boats have passed the obstruction. In addition, Blue is not entitled to room when she becomes overlapped inside Yellow. Although Yellow is subject to rule 16.1 when she changes course (because 18.2(d) does not apply at an obstruction), Blue breaks rule 18.2(c) when in position 3 she is no longer keeping clear. Penalize Blue. If Yellow continues when Blue cannot keep clear and contact is unavoidable, either between Yellow and Blue or between Blue and the obstruction, Yellow has not given Blue room under rule 16.1. Penalize both. Question 4 Would the answer be the same if Yellow changes course to parallel Blue in position 4 in order to give her room under rule 16.1? Answer 4 No. In this case, Yellow complies with rule 16.1 and Blue breaks rule 18.2(c). Penalize Blue.