Can exceptional behavior be considered ordinary?

The answer is Yes, according to Justice Wilmer in the 1955 case of Velox vs Viking Monarch, wherein one anchored vessel dragged anchor and collided with another when both were sheltering from a severe storm, when there were maneuvers and procedures that might have avoided it if taken.

The nicely put conclusion was:

"I have been reminded, and quite properly reminded, that no seaman can be called upon to exercise more than ordinary care (see Rule 2a below); but I think it is necessary to observe that when a seaman is called upon to face wholly exceptional conditions, ordinary care of itself necessarily demands that exceptional precautions may have to be taken."

In other words, it is the ordinary practice of seaman to take exceptional precautions in exceptional conditions, just as it is to take normal precautions in normal conditions.

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RULE 2 Responsibility

(a) Nothing in these Rules shall exonerate any vessel, or the owner, master or crew thereof, from the consequences of any neglect to comply with these Rules or of the neglect of any precaution which may be required by the ordinary practice of seamen, or by the special circumstances of the case.


(b) In construing and complying with these Rules due regard shall be had to all dangers of navigation and collision and to any special circumstances, including the limitations of the vessels involved, which may make a departure from these Rules necessary to avoid immediate danger.


See also our very convenient (free) presentation of the Nav Rules and all related  documents we call Pocket Nav Rules Handbook.

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I recall a case when a hurricane passed over a fleet of anchored sailboats and the ones that survived spent all night at the helm with the engine on and in gear taking the strain off the anchor line—and periodically fending off those boats that failed to do so.  I think we also have some pictures of this, which I will look for. It was a student of ours.