When running on a downwind leg, W became overlapped with L when almost two hull lengths to windward of her. Subsequently, M sailed into the space between L and W. All three boats finished with no narrowing of space between L and W and no contact. W protested M for taking room to which she was not entitled, citing rules 19.2(b) and 19.2(c). The protest was dismissed on the grounds that W had given room to M as required by rule 19.2(b). W appealed.

Rule 11 required W to keep clear of L throughout the incident. While M was clear astern of L, rule 12 required her to keep clear of L, and after she became overlapped with L rule 11 required her to keep clear of L. As the diagram shows, both M and W met these requirements. 

Because both W and M were required to keep clear of L throughout the incident, L was an obstruction to W and M during that time (see the penultimate sentence of the definition Obstruction). However, because L was a boat under way, L was not a continuing obstruction to them (see the last sentence of the definition Obstruction). When M became overlapped with W, rule 19.2(b) began to apply between them. It required W to give M room between her and the obstruction, unless she was unable to do so from the time the overlap began. As the facts clearly show, W was able to give M that room when the overlap began and continued to do so at all times until the boats finished. Therefore, W complied with rule 19.2(b). Rule 19.2(c) did not apply because the obstruction, L, was not a continuing obstruction. M broke no rule; therefore W's appeal is dismissed.

USA 1974/163