All sailors learn lessons at sea, and some of them are more urgent than others. Now that it's getting close to winter in the northern hemisphere, I'd like to make an important point about the dangers of hypothermia. Understanding this phenomenon and its application to sailors is one of the more important lessons for us all. I offer the following story to that end.
On February 10, 1983, a winter storm was building off the Virginia coast. Winds were from the northeast at 35 to 55 knots and seas were measured at four feet in the lower Chesapeake Bay and 20 to 40 feet out on the ocean. The ocean water temperature was 39 degrees Fahrenheit, and the air temperature was 37 degrees. It was a tough day to be out on the water.
Just before midnight the 600-foot ship Marine Electric departed Norfolk, VA, en route to Somerset, MA, with a load of coal. This was a routine trip for the Marine Electric—hauling coal along the East Coast—and the ship's chief mate even commented that he was not concerned with the weather, as the vessel had gone out many times under similar conditions.
As the Marine Electric proceeded to sea, weather buoys along the East Coast were recording gale-force winds (34 to 40 knots) with gusts well over 60 knots. Significant wave height, the average of the highest third waves passing these weather buoys, was reported at over 22 feet. Savvy mariners know that a significant wave height of 22 feet indicates the possibility of 44-foot seas.
The water depth along the route that the Marine Electric
was intending to follow was just over 100 feet. Waves begin to feel the friction of the ocean's bottom when the water depth is one-half a wave's length., and waves with heights of 44 feet have a length of approximately 500 feet. When a wave senses the ocean's bottom, its motion slows and its height increases, and waves with a length of 500 feet can ‘feel' the bottom in 250 feet of water. So it is easy to envision the waves in this storm slowing, and increasing in height to the point where they become unstable and then break.
Breaking waves are extremely dangerous because their orbital energy turns into horizontal energy. Most anyone who has been knocked down by not-so-tall breaking waves at the beach will be familiar with the power of horizontal wave energy. If your average beach-size breaking wave can knock a person down, imagine what a 44-foot breaking wave can do to a ship.
After dropping her pilot at Cape Henry, the Marine Electric cleared the Chesapeake Bay and steadied up on a northeast heading toward New England. Right away it was clear that she was making little progress, with waves breaking heavily across her deck. There was a lot of water coming down the decks, more than 400 feet in length, and the ship was rolling 15 degrees to either side.
During the day of February 11, the Marine Electric continued to make little progress. Speed over the bottom did not exceed 1.2 knots and was often as little as 0.3 knots, which is staggeringly slow for a vessel this size on the open sea. The skies continued to be overcast, there was rain and fog, and temperatures hovered in the 30s.
Then at 0251 on February 12, the Marine Electric, now 30 miles east of Chincoteague, VA, and barely 100 miles from the entrance of Chesapeake Bay, began going down by her bow. Her captain called the Coast Guard and explained his situation. He said he was thinking of abandoning ship.
At 0350 the Marine Electric developed a five-degree list to starboard. The list increased to 10 degrees in less than an hour. At 0415, with the ship now wallowing and steadily going down by the bow, the Marine Electric's captain ordered his 34-man crew to abandon ship, using the starboard lifeboat. As the crew was preparing to lower the ship's lifeboat the Marine Electric took a sudden roll to starboard and capsized. All 34 men were instantly thrown into the 37-degree water. Survival time in water this cold is less than one hour. The wind chill caused by the 45-knot winds and 39-degree air temperature was calculated at 21 degrees, which will cause frostbite to occur in less than 15 minutes.
Of the 34 crew only three survived and they were in the water for 65 minutes, until a Coast Guard helicopter arrived at 0520. Twenty-four bodies were recovered, most of whom died of hypothermia. Seven bodies were never recovered.
I dove on the Marine Electric four days later, on a day when the sun was shining, the sky was cloud-free and seas were flat. It was easy for us to find the ship as the USCG cutter Madronna, a 180-foot buoy tender, had become fouled in one of the Marine Electric's yellow and black polypropylene mooring lines, which was still attached to the ship and had uncoiled and floated to the surface.
Along with another diver from the Coast Guard's National Strike Force Dive Team, I followed the mooring line to the bottom in 120 feet of water. We found the Marine Electric
inverted on a hard sand bottom. The visibility was about 10 feet. There was a strong current flowing under the inverted hull, which alternately tried to pull us under the hull and then pushed us away. We pounded on the hull with our dive knives, an ineffectual but obligatory act to contact any survivors that might be trapped under the hull.
There was no response to our pounding so we ensured that the mooring line was firmly attached to the hull and headed back to the surface. In 120 feet of cold water we had only 10 minutes of bottom time using SCUBA gear to avoid the need for decompression. We were using double, 90-cubic-foot tanks, but rapidly consuming our air supply. On our way up to the surface, watching the sun grow brighter and listening to the sound of our air bubbles becoming less piercing, we realized there were no survivors. The once proud 600-foot Marine Electric was now a wreck on the ocean floor.
Hypothermia kills just as quickly as waves, wind, and seas. Cold water takes heat from the body 25 times faster than air of the same temperature. Winds can chill the body as well. A 20-knot wind takes 40 degrees Fahrenheit down to 30 degrees. Whether standing watch in an open cockpit, working on deck, or operating an inflatable, the possibility of having to abandon ship requires an awareness of hypothermia brought on by both cold air and water.
The best defense is staying on board and staying dry. If that's not a option, my advice is to invest in warm clothing, immersion suits, float coats, and thermal protective gear. And always be prepared for the possibility that you could end up in the water. In the winter, or wherever the water and the air are cold, stay warm to stay alive.
Hypothermia, the Reality
When sailors hear the term hypothermia, they conjure up scenes of icy waters and stormy conditions, but the reality is that even relatively benign water temperatures can threaten a person with hypothermia if they're immersed long enough. When water temperatures drop below 70 degrees F., they're considered cold, and your body will lose heat 25 times more rapidly in the water. Experts warn us that the normal person will only survive from one to six hours in water that's 50 to 60 degrees F., and exhaustion will set in even sooner.
If you do end up in the water, remember that attempting to swim will only increase the rate of your body's heat loss. To increase your survival time, keep your head out of the water, stay huddled if you're with others, and keep a positive attitude about your rescue. And always wear a personal flotation device because it won't only help you stay afloat, but it can also provide insulation to keep you warm.