If late at the start, he should know that the yacht is not disqualified (Council Y.R.A., 1881).
A good skipper will know Rules 18 to 29 by heart. By Rule 18:—
(a) A yacht going free keeps clear of a yacht close hauled.
(b) A yacht close hauled port keeps clear of a yacht close hauled starboard.
(c) When going free on opposite tacks the yacht with wind on port keeps clear.
(d) When going free on same tack the windward yacht keeps clear.
(e) A yacht with wind aft keeps clear of all others.
By (b) a yacht on port tack can be disqualified: first, if she strike or be struck by a yacht on starboard tack; secondly, if the latter luff, tack, or bear away to avoid being struck.
When yachts which overlap are rounding a mark or passing an obstruction, the outside yacht must give room to and keep clear of the inside yachts (Rules 19 and 20).
When yachts approach an obstruction close-hauled, and the leeward yacht cannot tack and clear the windward yacht, the helmsman of the former should 'hail for water' when required, and the two yachts must then tack together (Rule 22).