DETROIT – You’ve probably heard of the Gales of November -- those massive storms that hit the Great Lakes region in early November.
The reason that early November is prime time for these storms is that the Great Lakes are still relatively mild, but we’re also starting to get intrusions of cold air from Canada. When this cold air flows over the warmer Great Lakes, an unstable atmosphere develops -- we meteorologists call it the “Great Lakes Aggregate.” Some storm systems developing in the plains and moving this way get an extra boost from this situation, and become powerful storms. One such storm, more than 100 years ago, sank eight freighters on the Great Lakes and killed at least 235 men on those ships. You can read the article I wrote about that storm here.
Notorious storm of November 1975
But today, we’re talking about another, more notorious storm. Notorious because it happened more recently, in 1975 -- some of you reading this may remember the day the Edmund Fitzgerald sank -- and also because of Gordon Lightfoot’s famous song memorializing the ship and its crew.
Here’s the meteorological part of this sad story:
The Edmund Fitzgerald and another freighter, the Arthur M. Anderson, left western Lake Superior ports on Sunday morning, Nov. 9, 1975. The Andersen was headed toward Gary, Indiana; the Fitz was headed to Detroit. Both ships carried a full load of ore pellets.
Take a look at the above weather map for the morning of Nov. 9. You see a weak area of low pressure north of Lake Superior, and a relatively stronger low in Kansas. It’s this second low that became the storm that sank the Edmund Fitzgerald. The forecast that day was not unusual: This low was expected to travel northeast into the Great Lakes, and conditions would deteriorate. But the forecast did not convey anything about severe conditions, and no watches or warnings were posted. However, as it became more apparent that the developing storm was going to intensify, gale warnings were posted by early Sunday evening. Meanwhile, the Anderson and the Fitz continued chugging eastward, and their respective captains -- Jessie Cooper and Ernest McSorley -- were in regular radio contact.
Early on Monday, Nov. 10, the National Weather Service upgraded its gale warnings to storm warnings -- an indication that even stronger winds were now expected. Conditions started deteriorating on Lake Superior, and the Edmund Fitzgerald appears to have been more dramatically impacted than the Anderson, which is reflected in periodic statements over the radio by Captain McSorley, as reported in the National Transportation Safety Board’s official document about this incident:
1:50 PM: (we will) "continue on" (although we are) "rolling some."
3:30 PM: "I have a fence rail down, have lost a couple of vents, and have a list." Then, replying to a question from the Anderson about if his pumps were running, Captain McSorley replied, “Yes, both of them.”
4:10 PM: Captain McSorley advised the Anderson that both her radars were inoperative and asked that the Anderson keep track of the Fitzgerald and provide navigational assistance.
5:00 - 5:30 PM: Another ship that was communicating with the Fitz, the Avafors, reported that McSorley told them, "I have a bad list, I have lost both radars, and am taking heavy seas over the deck in one of the worst seas I have ever been in." The Avafors also overheard Captain McSorley say "Don’t allow nobody on deck."
7:10 PM: The Anderson advised the Fitzgerald of northbound traffic 9 miles ahead of her. In response to a question about her problems, the Fitzgerald replied, "We are holding our own." This was the last radio communication heard from the Fitz. When the Anderson’s radarscope was checked about 1920, there was no radar contact with her. Visibility increased about this time and although lights on shore more than 20 miles away and lights of a northbound vessel 19 miles away could be seen, the Fitzgerald, which should have been approximately 10 miles away, was not visible.
Around the time the Edmund Fitzgerald sank, the wind was blowing around 50 mph, with gusts reported by the Anderson of 70 to 75 mph, and waves of 18 to 25 feet. Compare this Nov. 10 weather map (below) with the Nov. 9 above -- you can easily see the intensification that took place as the storm progressed northeastward.
In its final report, the NTSB discussed two possible causes for the sudden sinking of the Edmund Fitzgerald:
Flooding water broke ship in half theory:
First, the increased weight of the flooding water could have caused a massive structural failure while the Fitzgerald was still on the surface, which caused the vessel to break into two sections. However, an analysis of various flooding conditions indicated that the stress levels from longitudinal bending moments were well below that which would cause a structural failure on the surface. The proximity of the bow and stern sections on the bottom of Lake Superior indicated that the vessel sank in one piece and broke apart either when it hit bottom or as it descended. Therefore, the Fitzgerald did not sustain a massive structural failure of the hull while on the surface.
Fitzgerald capsized theory:
Second, the reduced freeboard and loss of transverse stability from flooding could have caused the Fitzgerald to capsize. If three or less adjacent ballast tanks on the same side of the vessel were completely flooded, the Fitzgerald would not have capsized. The vessel also would not have capsized if water had entered only the cargo hold through openings between the hatch covers and the hatch coamings. In each case, the roll angle would not have been sufficient to produce a cargo shift.
However, under the combined effects of flooding two ballast tanks, the tunnel, and the cargo hold, the Fitzgerald would have capsized within minutes. If the vessel had capsized, however, all the hatch covers would probably have been torn away by the force of the shifting taconite pellets. The underwater survey of the wreckage showed that hatch covers Nos. 3 and 4 were still in place. The final position of the wreckage indicated that if the Fitzgerald had capsized, it must have suffered a structural failure before hitting the lake bottom. The bow section would have had to right itself and the stern portion would have had to capsize before coming to rest on the bottom. It is, therefore, concluded that the Fitzgerald did not capsize on the surface.
Hatch covers collapsed:
The National Transportation Safety Board determines that the probable cause of this accident was the sudden massive flooding of the cargo hold due to the collapse of one or more hatch covers. Before the hatch covers collapsed, flooding into the ballast tanks and tunnel through topside damage and flooding into the cargo hold through non-weather-tight hatch covers caused a reduction of freeboard and a list. The hydrostatic and hydrodynamic forces imposed on the hatch covers by heavy boarding seas at this reduced freeboard and with the list caused the hatch covers to collapse.
Contributing to the accident was the lack of transverse watertight bulkheads in the cargo hold and the reduction of freeboard authorized by the 1969, 1971, and 1973 amendments to the Great Lakes Load Line Regulations.
Whatever caused the Edmund Fitzgerald to sink, it happened fast. And since it would take anywhere from 10 to 30 minutes to deploy a lifeboat, there was no chance that anybody could survive the ship’s catastrophic failure.
Twenty-nine brave souls lost their lives, and took the story of what exactly happened to the Edmund Fitzgerald to their watery graves at the bottom of Lake Superior.