Collided with the Hawaiian Pilot [sister ship] in foggy conditions and sank within 30 minutes.

0440 July 14th 1953
S/S Hawaiian Pilot collided with the vessel -- striking her on the starboard quarter -- vessel heavily damaged in danger of sinking
1330 July 15th 1953
Casualty reports made out & turned in to US Coast Guard
[Reference: Official Log of the Jacob Luckenbach, signed by Captain and Purser]

In this case, both vessels, operating under fog and low visibility conditions, saw each other on their radarscopes while they were miles apart. Both vessels had ample opportunity to plot a series of two or more bearings and ranges to determine the course and speed of the other. Neither vessel did this. Had the Master of the Hawaiian Pilot taken this precaution, he would have known that the object he mistakenly assumed to be the San Francisco Lightship on the radarscope was, in reality, the Jacob Luckenbach; and, collision, no doubt, would have been avoided.