EPIRB Rescue Search Patterns: Part 3

Above: the Coast Guard's airborne search patterns as their soon-to-be 40-hour search for the fishing vessel Lady Luck spreads out along the southern Maine coast of New England (US, near Boston). Note the tighter grid the Coast Guard ran northeast of the EPIRB's initial location, the looser grid they ran to northeast. The Coast Guard left the Lady Luck's EPIRB in the water the hopes that its drift would mimic that of the fishing vessel's lifeboat or two-man crew in their survival suits (also known as immersion abandonment suits. (Double-click the image to enlarge)

Below: the Coast Guard soon had two aircraft and the cutter Seneca on scene. The search grids run by the searchers was now broad, widely-spaced, loose. Note how the aircraft, following drift models, focus their flyovers southeast of the EPIRB initial location.

Below: the search continues to evolve and includes another Coast Guard cutter, the Flying Fish, and two aircraft. The search patterns dip, far southeast of the EPIRB's initial location, to waters northeast east of Boston, Ma., and include cursory runs along Portland, Maine's shipping lanes and part of the intricate coast of downeast Maine: (Double-click the image to enlarge)
Below: the saddest image. When the Coast Guard finally calls off what had been a 40-hour search for the two young crewmen of the EPIRB-equipped fishing vessel Lady Luck, the search has covered 5,000 square miles. Note how dense and thorough the search pattern appears in areas adjacent to Lady Luck's EPIRB transmission, and how loose, yet specific, the outlying search patterns are to the east, northeast, and southeast: (Double-click the image to enlarge)


Read parts 1 and 2 and 5 of this 5-part series. Part 4 isn't written yet:
Part 1
Part 2
Part 5
copyright 2008Just Another Guy Named Dave
images USCG

EPIRB Search and Rescue Patterns: Part 2

Above: the that-morning patterns run by Coast Guard and Navy aircraft in their search for survivors of a Massachusetts commercial fishing boat whose EPIRB activated offshore in the dead of a New England winter. Note that the Coast Guard's dirft model sent them on a pattern that extends far southeast and east/northeast of where the EPIRB was initially spotted by an overflying Coast Guard jet.

If Coast Guard or other search-and-rescue air and seacraft are in search of us after receiving word, via personal locater beacon, SPOT, VHF radio maday or friend [link forthcoming], that we are lost or in trouble, they'll make many assumptions about where we'll drift as time wears on.

Their predictions come from drift models (formerly JAWS, now SAROPS) that take into account surface current, tide and wind.

Created by tides and winds, surface currents tug us, along with our gear and kayaks, in reasonable-to-assume directions, which gives search-and-rescue personnel a leg-up on where in a vast ocean or bay to concentrate their resources. But we drift differently than a sailboat, which drifts differently from a person in the water, which drifts differently than a sinking fishing vessel, etc.

The Coast Guard takes into account all those differences - which drives home the point of identifying in a mayday what kind of boat we're in.

The Coast Guard factors all of those differences into how they calculate their search model for us or whoever has gone missing.

In the image above , you'll notice that the Coast Guard in New England (US, Boston area) made easterly assumptions about where the crew of Lady Luck, a 55-foot Newburyport, Ma. commercial fishing boat, had drifted in the several hours after the sunken vessel's EPIRB emitted its distress signal.

Were the search for one of us, equipped with a personal locater beacon [link forthcoming] or not, the Coast Guard would assume something similar about our drift.

Since time is of the essence in all rescues, and especially in this case, given that the Lady Luck sank during the winter, the Coast Guard concentrated their densest search patterns where they assumed the crew, in either survival suits or a life raft, would have drifted.

The image below shows the later, that-afternoon search. Note how the drift model has begun making different predictions now that time has worn on and conditions have changed: the densest searches now took place far northeast, and southeast, of where the EPIRB was initially located.

By now a Coast Guard cutter and Canadian helicopter have joined the search. The search patterns take on an even more easterly aspect, as well as north and northeast, of the of the initial sighting of the EPIRB:


Later in the day the search shifited further east, with the densest patterns running north and east, but trending southeast, of the original sighting:

The search would grow ever wider in the coming 36 hours. Neither survivors nor the Lady Luck -- aside from assorted pieces of commercial fishing gear that floated off the sinking boat -- were recovered.

The search pattern evolved further, as you'll note in the third post.

To read more about the personal locater beacons which act as stand-ins for EPIRBs for kayakers in remote waters, and about the newest addition to emergency electronics, the SPOT beacon, which sends text or email messages and Google Maps showing your exact location, to friends or emergency personnel, wait a few days while I post up photos and video I shot of one of the former, available from plbrentals.com

copyright 2007Just Another Guy Named Dave
images courtesy USCG
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EPIRB Rescue Search Patterns: Part 1

Above: Coastal New England (US). The first in a series of images illustrating the efforts Coast Guard units expend on search-and-rescue operations activated by EPIRBs, or emergency position indicating radio beacons.

Search Amazon.com for personal locater beacons

In order to develop a search plan, we take the crew's last known position, wind, wave and current sea states, and develop a simulated scenario, known as a drift model, in a computer. We fast-forward the model from the time of their last known position to our current time in order to find a most likely position the victims could be at.
--- Coast Guard petty officer describing Coast Guard search and rescue

An EPIRB is a serious piece of emergency equipment you'll see lashed to the cabin housing of most every commercial fishing boat in the US, from the smallest lobster boat to the largest trawler.

They're expensive, bulky, not form-factored to the tastes of consumers, and are cousin to the myriad $500 personal locater beacons, or plbs (read more about plbs in earlier posts) sold by outdoors outfitters like REI and marine suppliers like West Marine.

Above: a 406 EPIRB fastened to the cabin top of a day-boat seiner in Gloucester, Massachusetts. EPIRBs activate automatically during a boat's sinking, or when submerged in nine feet of water. Size is that of about two large grapefruits.

A couple of winters ago New England Coast Guard units responded to an EPIRB transmission (EPIRBs do not transmit voice data) from the 52-foot commerical fishing vessel Lady Luck, a recently upgraded boat skippered and crewed out of Newburyport, Ma. by two men in their 20's.

The EPIRB activated when the Lady Luck sank while enroute to Gloucester, Massachusetts, my hometown.

The EPIRB gave the Coast Guard a fix of 43.20.4 north , 69.54.8 west, or about 30 miles east of Cape Elizabeth, Maine, just past where New Hampshire's token coastline gives way to the sprawling east-sliding unravellings of Maine.

After zeroing in on the EPIRB's electronic signal, a Coast Guard jet visually sighted the EPIRB's flashing strobe but not the Lady Luck.

The jet circled and dropped a life raft in the hopes that the EPIRB and the raft would follow the drift pattern of the survivors.

A Coast Guard helicopter ran at first light that day the search pattern shown below: wide pie slices radiating out from where the EPIRB was first located:
After the helicopter's initial search , a helicopter and Navy plane ran a series of tightly-spaced and overlapping parallel tracks:

As you can see, the tightest grids were flown south and southeast of the EPIRB's initial location.

The drift model shows that the Coast Guard, tracking the drifting EPIRB and running a drift model, assumed that survivors would float southeast: New England's prevailing winter winds are northwesterlies.

The search patterns began to vary greatly over time, varying with the Coast Guard's ever changing dirft models of the survivors over time.

Above: Sean Cone, owner of Lady Luck, unloads fresh cod at the Pigeon Cove/Whole Foods market in Gloucester. Whole Foods' fish buyers and processing plant are dockside in town. They buy much of the local fleet's groundfish (cod, haddock, flounder, etc.) Peter Prybot photo/AP/Gloucester Daily Times

As an aside, know in advance that, sadly, neither the Lady Luck nor its crew were found. The Lady Luck sank in 500 feet of water and was later videographed by an underwater probe as part of the Coast Guard's investigation into why the vessel sank.

It's unlikely Sean Cone, 24, the ship's captain and owner, and his crewman, Dan Miller, 21, had time to don survival suits.

Above: a 406 EPIRB fastened to the cabin door of a lobster boat docked at the State Fish Pier at Gloucester, Massachusetts. Note the unit's strobe light and bulky whip antenna.

images and text copyright 2007Just Another Guy Named Dave
map images courtesy USCG
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copyright 2010 Just Another Guy Named Dave
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Hey, buy me something from my Amazon wishlist.

copyright 2010 Just Another Guy Named Dave
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