Thursday, January 21, 2010

Lessons Learned—Thirteen Perish in Water Tour Casualty—Part I

Excerpt from U.S. Coast Guard “Proceedings of the Marine Safety & Security Council” magazine by Ms. Barbara Chiarizia, executive editor, Proceedings.


Lessons learned from USCG casualty reports are regularly featured in Proceedings of the Marine Safety & Security Council magazine. These articles explore marine incidents and the causal factors, outline the subsequent U.S. Coast Guard marine casualty investigations, and describe the lessons learned as a result.

It is important to note that lives were lost in some of the marine casualties we present. Out of respect for the deceased, their families, and surviving crewmembers, we do not mention the name of any person involved.

On May 1, 1999, the passenger vessel Miss Majestic departed for a trip on Lake Hamilton, near Hot Springs, Ark. The vessel, a rare hybrid craft, was originally built for military use as an “amphibious truck.” As such, it combined elements of an on-road vehicle with the ability to operate as a waterborne passenger vessel.

Since they operate on both land and water, these vehicles are commonly referred to as “ducks” or “duck boats,” and are used primarily for commercial land and water tours. This was the type of outing passengers planned on that pleasant day in May. The “water” portion of the tour normally lasted about a half-hour, but minutes into the tour, the operator realized something was wrong.

Tragedy Strikes
According to the U.S. Coast Guard casualty investigation report,

“Approximately seven minutes after entering the water, [the operator] felt the [vessel] react sluggishly … and list to port.”

The operator and several passengers also noticed water washing onto the deck. The operator attempted to turn the vessel back to shore. The vessel continued to take on water, however, and sank in less than 30 seconds.

Of the 21 persons aboard, only eight survived.

How could this have happened? Why did it sink so quickly? How did 13 people drown just yards from shore? What can be done to prevent anything like this from happening again?

These were among the questions U.S. Coast Guard investigators sought to answer.

The Investigation Begins
The USCG investigation initially focused on what caused the vessel to take on water. Investigators determined that the vessel flooded through the aft shaft housing after a seal became dislodged, but this should not have caused the vessel to sink so quickly.

The Timeline for Tragedy
During an inspection of the vessel on February 23, 1999, the Coast Guard investigator noted nine items that needed attention and left a work list with the owner. The investigator considered most of these repair items to be minor, and only entered two into the inspection record:

“ … the owner is in process of installing … high-level bilge alarms required by 11 Mar 99. Owner is researching the availability of flammable vapor detection system required by 11 Mar 99.”

The owner made arrangements to address the work list and continued operation of the vessel. He later stated that he was unaware of the March 11, 1999, deadline, and neither of the noted items was installed on the vessel by May 1, 1999—the day of the incident.

Several days before the incident, the vessel’s operator noted problems and cut the tour short. Subsequent examination revealed water in the bilge and a hole in a boot seal to the aft shaft housing.

The mechanic performed regular maintenance, replaced boot seals, and returned the vessel to service on May 1. The mechanic later stated that he did not “water-test” the repairs because it was not company policy.

At some point, the original hinge assembly for the aft shaft housing had been removed (apparently to allow access to lubricate the u-joints). Unfortunately, since the hinge assembly was missing, the seals were subjected to stresses they were not designed to withstand.

In part II, we will further examine the incident and subsequent Coast Guard investigation.


For more information:
Full article is available at www.uscg.mil/proceedings. Click on “archives” and "2008 Volume 65, Number 2" (Summer 2008: Focus on Safety).

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

Online survey available at: http://www.uscg.mil/proceedings/survey.asp.

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

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