a. Improper lookout
This term encompasses failure to observe the other vessel immediately prior to collision and failure to check changes in the other vessel's compass bearing, despite having observed the other vessel until a certain point previously, to ascertain whether risk of collision existed - in other words, insufficient observation of movement - resulting in a non-compliance with steering and sailing rules (not taking proper action to avert collision) or failure to sound signals.
Of the 410 vessels considered to have been keeping an improper lookout, 270 were found not to have observed the other vessel immediately prior to collision, while 140 were condemned for insufficient observation of the movement of the other vessel. Vessels cited for the latter offense accounted for about 34% of all vessels criticized for improper lookout, with reasons given for this assumption that the other vessel would pass and clear without incident and presumption of the other vessel's course, both of which were cited for 33 vessels; assumption of the other vessel's speed without actual knowledge, indicated in cases involving 23 vessels; improper assessment of the other vessel's condition, given in cases involving 18 vessels; assumption that problems would not develop immediately, cited in accidents involving seven vessels; distraction by a third vessel, given for accidents involving five vessels and distraction by something else, indicated in accidents involving six vessels.
b. Non-compliance with steering and sailing rules
This term encompasses failure of a vessel to take proper action to avert collision despite having observed the other vessel and being aware of the risk of collision. Of the 194 instances in which this cause was cited, 72 - a majority - involved failure to observe rules on the ordinary practice of seaman, while 41 involved failure to comply with rules of conduct in restricted visibility situations and 26 involved failure to observe rules on crossing situations.
