Safety alert warns about ignoring vessel alarms
The U.S. Coast Guard is urging mariners to heed all vessel alarms, including those considered to be a “nuisance” or unrelated to safe operation.
Coast Guard marine inspectors identified two recent incidents in the Pacific Northwest involving Mitsubishi Heavy Industries steering gears. The gear systems’ alarms sounded when crew moved the ship’s rudder through its full range of motion, according to a Coast Guard safety alert published Oct. 26.
“The alarms indicated that ‘hydraulic lock’ events had occurred,” the alert said. “Each time, the alarm was simply acknowledged by the crew and the steering gear adequately moved the rudder. However, no further investigation was conducted to identify the cause of the alarm.”
The alarm occurred on steering gears installed aboard relatively new ships, and the safety alert suggested “a false sense of operational safety develops” when alarms are repeatedly heard but ignored.
Neither of these incidents resulted in a casualty, but investigators say the alarm in question could portend a serious mechanical flaw. The Mitsubishi steering gears use a series of valves and sensors to ensure steering machinery is working properly. Proximity switches indicate movement of certain valves, and over time failure to acknowledge such movement triggers an alarm.
“In each of the two cases profiled here, the proximity switches were faulty and required replacement,” the alert said. “Ignoring the problem meant that although the rudder moved as expected in these two cases, the lack of properly functioning proximity switches might result in a failure to detect if the rudder had not moved, since crewmembers had trained themselves to ignore the alarm.”
The Coast Guard urges operators to adopt safety management systems that require crew to identify the cause of nuisance alarms and take steps to correct the problem. The service also recommended that operators prohibit crew from pinning or securing alarm acknowledgement buttons.
Dry dock sinks off California during transit
A 528-foot dry dock under tow from Seattle to Mexico took on water and ultimately sank roughly 40 miles west of San Francisco.
The 4,200-hp tugboat Ocean Ranger was hauling the dry dock when its crew noticed it listing during transit, according to the Coast Guard. The tug headed west, away from shore, before detaching its towline. The dry dock sank at about 0200 on Oct. 26 in roughly 3,000 feet of water. There was no sign of the massive dry dock the next morning when a Coast Guard helicopter flew over its last known location.
Nobody aboard the tug was hurt, and there was no environmental damage from the sinking. The Coast Guard said hazardous materials were removed from the dry dock in Seattle before the voyage began.
The 26-year-old Ocean Ranger is operated by Western Towboat Co. of Seattle. The 117-foot-long boat has twin Caterpillar 3516 engines and 2,800 feet of 2.25-inch Nordic towing wire.
It’s not clear why the dry dock started taking on water, and the Coast Guard is investigating the incident.
Freighter loaded with fertilizer grounds off NC coast
The Coast Guard temporarily closed the Beaufort Inlet Channel to deep-draft ships earlier this month after a freighter loaded with fertilizer ran aground off the North Carolina coast.
The 590-foot Pola Palekh was carrying 35,800 metric tons of fertilizer and about 27,000 gallons of fuel oil when it grounded at about 1315 on Nov. 17. The accident occurred near buoy 16A in the channel, according to the Coast Guard.
Tugboats helped pull the ship off the shoal and then escorted it to the nearby Morehead City State Port Terminal, the Coast Guard said. The cause of the accident is under investigation.
Qingshan Shipyard in China built the Malta-flagged cargo ship in 2014, and Pola Maritime LTD operates the vessel.
Casualty flashback: November 1966
The 603-foot laker Daniel J. Morrell was sailing in Lake Huron toward Taconite Harbor, Minn., on Nov. 29, 1966, when it encountered a severe fall storm. The 60-year-old vessel was making for the protection of Thunder Bay, Mich., when it broke in two amidships and sank soon afterward north of Pointe Aux Barques, Mich. Twenty-eight of the 29 crewmembers died.
The ship, operated by Bethlehem Steel, was making its last scheduled run of the season when it left Buffalo, N.Y., three days before the accident carrying only ballast. Although forecasts called for gale conditions, the weather steadily worsened late on Nov. 28 and into the next morning. Other vessels in the area observed 25-foot swells and 70-mph winds.
Dennis Hale, the lone surviving crewmember, told investigators he awoke at about 0200 on Nov. 29 to a loud bang followed by another bang a few minutes later. He soon realized the light in his bunkroom — located on the starboard-side forward spar deck — was not working, according to the Coast Guard investigation report. Moments later, the general alarm sounded.
Wearing only his shorts, Hale grabbed his life jacket and pea coat and went out to the starboard passageway, where he saw the center portion of the ship sitting higher in the water than the aft portion, according to investigators. Several crew, including the master, first mate and second mate, were already sitting in a life raft waiting for the ship to sink.
“Although there were no lights in the midships area, Hale indicated he did observe that the crack in the vessel started in the area of the gunwale bar, starboard side, in the general area of hatches 11 and 12, and proceeded across to the port side,” the report said. “The forward section’s deck at the starboard side seemed to drop lower than the after deck in a twisting effect. Hale could see metal sparks as the two sections of the vessel rubbed together.”
When the ship parted it lost power to the bow section, preventing the crew from sending a distress signal. As a result, the Coast Guard did not realize the ship was missing until about 30 hours after the accident.
Soon the ship broke into two sections. The stern appeared to be pushing into the forward section, which then moved perpendicular to the stern, which remained under power. As the forward section sank, the raft and crew were washed overboard. Hale landed within 10 feet of the raft and climbed in, along with three other sailors. By 0600, two men were dead, and about 10 hours later the third sailor died. Hale was in a semi-conscious state when the Coast Guard rescued him at about 1600 on Nov. 30.
The National Transportation Safety Board determined the cause of the sinking was structural failure of the main hull girder amidships. Stress on the hull girder from the wind and waves also contributed to the accident.
After the accident, the Coast Guard recommended that vessels carry an emergency radio with its own power source to transmit when ship power is lost. It also recommended that vessels carry a buoy that transmits a signal when a ship sinks.
