Tuesday, September 28, 2010

Lessons Learned—A Great Lakes Fishing Vessel Sinks Within Seconds—Part III

Excerpt from U.S. Coast Guard “Proceedings of the Marine Safety & Security Council” magazine. Click here for Part I and Part II.

An integrated tug and barge (ITB) transited the waters off Port Washington between 11:30 a.m. and 12:05 p.m. on December 11, 1998. Of the 26 vessels investigated, this was the only one in this area around this time.

The visibility of the ITB operator in the pilothouse is restricted for some distance forward of the barge. Even so, the vessel met the visibility requirements of Title 33 CFR 164.15.

Contributing to the Casualty
Lack of visibility from both the ITB and the Linda E most likely contributed to the collision. The window arrangement of the downed vessel, with widely spaced portholes, was not conducive to a wide view of surrounding waters.

It is possible that the sun just off the port bow of the ITB shone directly into the pilothouse and obscured the Linda E. Also, due to the length of the barge, once a small vessel was close off the bow, the tug operator’s view would be obscured, as depicted here.

Additionally, the investigators concluded that the radar on the ITB was not monitored adequately or not used properly. Other contributing factors included the diverted attention of the ITB operator who was standing watch. The mate was performing a non-navigation activity that distracted his attention from activities essential to navigation—like looking out for other vessels.

The Incident
MSC graphic analysis illustrates how the accident may have taken place. Upon collision, the heel of the fishing vessel would have caused rapid downflooding through the submerged large door openings, sinking the vessel within seconds.

It is possible that the crew aboard the ITB neither felt, heard, nor observed the collision. Marks and damage to the barge suggested the collision was brief and light.

Even if the collision were more severe, the resulting change in velocity of the barge would not have been detectable. Noise from generators and activity on the barge may have prevented hearing a collision, and the Linda E most likely sank so quickly that it did not pass far enough aft to be seen by anyone on deck of the barge or in the pilothouse of the tug.

In part IV we will examine the lessons learned from this incident.

For more information:
Full article is available at www.uscg.mil/proceedings. Click on “archives” and “2006 Volume 63, Number 2” (Summer 2006).

Subscribe online at http://www.uscg.mil/proceedings/subscribe.asp.

Direct requests for print copies of this edition to: HQS-DG-NMCProceedings@uscg.mil.