Technical Issues: Lightering, Rescue Towing, Safe Haven, Damage Stability

Bound for Portland, Maine, from the Caribbean, a 21,000-DWT product tanker carrying a full load of distillate (34º API) strands on a rock off Portland Head Light in Casco Bay, Maine. The tanker is foreign owned and registered. It is fall, and the weather is deteriorating. The situation unfolds at two levels of complexity.

Strand, Refloat

The ship comes off the ground on the incoming tide. The ship is capable of navigation but is leaking. The Coast Guard refuses entry into the port until the ship has been lightered and is not a pollution hazard.

Strand and Refloat, with Damage

The propeller is damaged in the strand such that the vessel is incapable of navigation. The ship is not expected to come off the strand on the incoming fide, which will occur six hours after the initial notification of the stranding. The estimated remaining ground force is 1,350 tons. Major pollution is thought to be from ship's bunkers. Seas are 4 feet, choppy, and building. The weather forecast calls for winds and seas to build for 19 hours, with a northeaster continuing for 48 hours. The ship is leaking from three ruptured center tanks and possibly from the engine room double-bottom bunker tanks.


Technical Issues: Refloating, Cargo Offloading, Heavy-lift Capability

Two scenarios are possible. In the first, a number of bulk carriers are anchored in Anchorage L-C to the west of Thimble Shoals Channel waiting to load coal in Norfolk, Virginia. A sudden and fierce summer squall causes one of the colliers to drag its anchor to the east. She is light and strands on rip rap on the eastern bridge island of the Thimble Shoals Channel. The double bottom is flooded to the extent that the ship is about 12,000 tons aground. The ship is projecting into the channel but due to channel width does not block the channel. The second scenario assumes that the bulk carrier is loaded, loses steering, and strands in the same position.


Technical Issues: Rescue Towing, Damage Stability

A roll-on/roll-off (RO/RO) ship carrying heavy vehicles and containers under charter to the Military Sealift Command is caught off Cape Hatteras in heavy weather 40-knot winds from the northeast with 16-foot waves. The ship loses power, is unable to maintain its heading, and takes heavy seas broadside. The heavy rolling causes several vehicles to break loose and eventually puncture the ship. The flooding rate is slow but steady. The weather conditions and the danger of further cargo shifts preclude the crew from taking action to control the flooding. The ship is 20 miles east of Cape Hatteras and 125 miles from the entrance to Chesapeake Bay. If a response cannot be marshalled within 12 hours, the chance of saving the ship is less than 50/50.

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