44 LAWS GOVERNING MARINE INSPECTION 



(c) A power-driven vessel which detects the presence of another 

 vessel forward of her beam before hearing her fog signal or sighting 

 her visually may take early and substantial action to avoid a close 

 quarters situation but, if this cannot be avoided, she shall, so far as 

 the circumstances of the case admit, stop her engines in proper time to 

 avoid collision and then navigate with caution until danger of collision 

 is over. 



Part D. — Steering and Sailing Rules 



preliminary 

 33 U.S.C. 1078 



1. In obeying and construing these Rules, any action taken should 

 be positive, in ample time, and with due regard to the observance of 

 good seamanship. 



2. Risk of collision can, when circumstances permit, be ascertained 

 by carefully watching the compass bearing of an approaching vessel. 

 If the bearing does not appreciably change, such risk should be deemed 

 to exist. 



3. Mariners should bear in mind that seaplanes in the act of land- 

 ing or taking off, or operating under adverse weather conditions, 

 may be unable to change their intended action at the last moment. 



4. Rules 17 to 24 apply only to vessels in sight of one another. 



33 U.S.C. 1079 (Rule 17) 



(a) Wlien two sailing vessels are approaching one another, so as 

 to involve risk of collision, one of them shall keep out of the way 



of the other as follows — 



(i) When each has the wind on a different side, the vessel 

 which has the wind on the port side shall keep out of the way 

 of the other. 



(ii) When both have the wind on the same side, the vessel 

 which is to windward shall keep out of the way of the vessel which 

 is to leeward. 



(b) For the purposes of this Rule the windward side shall be deemed 

 to be the side opposite to that on which the mainsail is carried or, 

 in the case of a square-rigged vessel, the side opposite to that on which 

 the largest fore-and-aft sail is carried. 



33 U.S.C. 1080 (Rule 18) 



(a) When two power-driven vessels are meeting end on, or nearly 

 end on, so as to involve risk of collision, each shall alter her course 

 to starboard, so that each may pass on the port side of the other. This 

 Rule only applies to cases where vessels are meeting end on, or nearly 

 end on, in such a manner as to involve risk of collision, and does not 

 apply to two vessels which must, if both keep on their respective course, 

 pass clear of each other. The only cases to which it does apply are 

 when each of two vessels is end on, or nearly end on, to the other; 

 in other words, to cases in which, by day, each vessel sees the masts of 

 the other in a line, or nearly in a line, with her own ; and by night, 

 to cases in which each vessel is in such a position as to see both the 

 sidelights of the other. It does not apply, by day, to cases in which a 

 vessel sees another ahead crossing her own course; or, by night, to 



