The Witch of November: What sank the Edmund Fitzgerald

CLEVELAND - Its been 35 years since the ore carrier, S.S. Edmund Fitzgerald, sank during a monster storm, known as the "Witch of November" on Lake Superior. The ship now lies broken, in two pieces, in more than 530 feet of water, just 17 miles from Whitefish Bay, Michigan. All 29 crew members, many from Northern Ohio, lost their lives.

Even now, the questions still linger. What sank the Edmund Fitzgerald? Did the ship hit ground in shallow water causing damage to the hull? Did the ship then begin taking on water and list so badly the it easily rolled over in the stormy conditions? Was this enough to sink the Fitzgerald or was there something else?

Recent research sheds some new light on what contributed to the sinking of the ship, which was, at the time, the largest ore carrier sailing the Great Lakes.

A reanalysis of this event was done in 2005 by the National Oceanic and Atmospheric Administration (NOAA) , in conjunction with the National Weather Service. The study used the latest computer technology along with weather measurements from that fateful November night in 1975 to re-create the weather conditions present at the exact time the Fitzgerald sank. 

The computer simulation ran from November 9th, 1975 to the early morning hours of  November 11, 1975. The analysis showed that at 4pm on November 10th there were two separate areas of high wind over Lake Superior. One of them had speeds in excess of 50 mph and the second had winds in excess of 46 mph. The highest winds occurred over the southeastern part of Lake Superior where the Edmond Fitzgerald was heading. Wave heights increased to near 19 feet by 7pm, November 10th and winds were exceeding 50 mph over most of southeastern Lake Superior.

The Edmund Fitzgerald sank at the eastern edge of the area of high wind where the long fetch (distance that the wind blows over water) produced significant wave heights averaging over 23 feet by 7pm and over 25 feet at 8pm. The computer also showed that one in 100 waves were likely reaching heights of  36feet and one out of every 1000 waves could have been as high as 46 feet! Since the ship was heading east-southeastward, the waves were likely causing the Fitzgerald to roll heavily.

At the time of the sinking, the ship, Arthur M Anderson, reported NW winds of 57 mph which matched the computer analysis output of 54 mph. The computer analysis showed that the maximum sustained winds reached near hurricane force, sustained at near 70 mph with gusts to 86 mph at the exact time and the exact location where the Fitzgerald sank. What's more, the computers also plotted the highest waves between 30 and 40 feet tall at the exact location and time of the sinking!

The National Transportation Safety Board determined 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-weathertight hatch covers" caused the ship to list heavily to one side.

The new computer analysis adds the final piece to the puzzle of the ill-fated journey of the Edmund Fitzgerald: A listing ship, taking on water, sitting about 20 feet out of the water, encountered waves 40 feet high at the exact time and location where the ship sank.

See: Reexamination of the 9–10 November 1975 “Edmund Fitzgerald” Storm Using Today’s Technology BY THOMAS R. HULTQUIST, MICHAEL R. DUTTER, AND DAVID J. SCHWAB; American Meteorological Society 2006.

Thanks to Fred Pickhardt, Ocean Weather Services.