New GPS buoy saves adrift sailorJan 1, 2003
A dramatic search-and-rescue (SAR) operation performed by the Canadian Coast Guard in October recovered 10 of 15 crewmembers of a freighter that sank off Newfoundland.
One survivor, the vessel's chief mate, who was washed from the vessel by a boarding wave as the crew struggled to release the life raft, lived through the adventure after spending 19 hours adrift in the ocean. His survival hinged on several unique factors, most notably the deployment of an experimental drift buoy.
On the afternoon of October 23 the 5,000-ton refrigerated freighter Vanessa, en route from Sweden to Colombia with a cargo of explosive ammonium nitrate fertilizer, took on a severe list to port and sank shortly after part of her cargo shifted during a storm. The ship's 15-man crew reportedly had only minutes to issue distress calls and abandon ship before Vanessa rolled over and went down about 450 miles southeast of Newfoundland in 20- to 30-foot seas and winds of 40 to 50 knots.
Responding to distress calls, Canadian Coast Guard and rescue officials in Halifax, Nova Scotia, and St. John's, Newfoundland, worked rapidly to get planes in the air and to coordinate the efforts of any ships that might be in the area of the sinking.
The Cape Roger, a 200-foot Canadian Coast Guard cutter that arrived on scene about 10 hours after the sinking, was given a search pattern by the Rescue Coordination Center in Halifax based on data being broadcast from a pair of tin-can-sized buoys dropped out of a tube in the belly of a C-130 aircraft earlier in the day. Nine of Vanessa's crew, adrift in the vessel's life raft, were picked up by a merchant vessel that was also diverted by the RCC. Still missing were six crewmembers, including the chief mate, who had been washed from Vanessa's aft deck by a boarding wave before the life raft had been launched.
The so-called Self Locating Datum Marker Buoys (SLDMB), developed through a joint effort of the Canadian government and a Halifax company named Seimac Ltd., are packed with a tiny GPS receiver and a satellite transmitter, and they have the ability to simulate the drift characteristics of either a life raft on the surface or a human body mostly submerged in water. The Vanessa rescue was the first non-experimental deployment of the Seimac buoys by Canadian rescue services. The result was an enhanced computer prediction of the ideal search pattern, coordinated by the RCC's computer software package, including the actual drift positions broadcast by the buoys.
It is likely that the Vanessa went down somewhere near the southern side of a warm eddy where there might have been a current moving to the northwest, according to Jenifer Clark, a Gulf Stream expert based in Upper Marlboro, Md.
"Before we got the buoy info we were scratching our heads trying to figure out why the life raft had not drifted downwind as far as might be expected," said Paul Rudden, rescue controller in Halifax. He noted that the life raft was found only 3.4 miles southeast, or downwind, of the reported sinking site.
Just after dawn, after recovering one body floating in a lifejacket, lookouts on the Cape Roger spotted two more bodies floating in a head-up position, seemingly clinging to each other, although clearly dead. The ship's Zodiac recovery boat moved in to pick up the bodies as Cape Roger hovered about 50 feet away, with her captain observing from the bridge wing.
"They certainly appeared to be dead, but that boat crew got the surprise of their lives when all of the sudden one of the bodies started lifting its arms," said the captain.
The survivor was Chief Mate Henry Almonte, who at that point had been in the 60° water 19 hours since being washed off Vanessa's aft deck. He was found 8.7 miles west-northwest, or upwind, of the site where Vanessa was reported to have sunk. His dead companion was the ship's chief engineer.
As the rescue work continued, the ship's crew picked up two more bodies. They located the damaged life jacket of a crewmember who was never found. The last body was located 13.5 miles upwind of the sinking site.
Among the first to cheer the arrival of survivors in port were those from the Canadian Coast Guard's rescue coordination center in Halifax. For them the successful rescue marked the beginning of a new chapter in SAR technique. "We'll definitely be using the technology of these little buoys again," said Paul Ruddin, the rescue controller. "We concluded right then that the first priority of the first arriving aircraft in any situation where there are people missing in the water will be to get those buoys in the water."
The U.S. Coast Guard has been slow to incorporate GPS-equipped drift buoys in real-life emergencies, mostly for budgetary reasons, according to Arthur Allen, an oceanographer at the Coast Guard's Research and Development Center in Groton, Conn. A search-and-rescue operation in 1993 successfully recovered a survivor from the ship Salvadore Adundi, which sank in the Gulf Stream off Canada, by using data from an Argos-equipped drift buoy.
One of the advantages of GPS over Argos, according to Allen, is that GPS data is instantaneous, making data immediately available to rescue crews.
American drift buoys with GPS continue to be tested, particularly for the recovery of jettisoned marijuana bails off the Florida coast, according to Allen, but have not yet been used in an actual search-and-rescue operation.