Inside the S.S. Edmund Fitzgerald
The FITZGERALD was a conventional "straightdecker" Great Lakes bulk cargo vessel. It was 729 feet long, 75 feet in breadth, 39 feet in depth, 13,632 gross tons, and 8,686 net tons. It was propelled by a 7,500-hp, steam turbine and was built as Hull 301 at Great Lakes Engineering Works, River Rouge, Michigan, in 1958. The vessel was owned by Northeastern Mutual Life Insurance Company and operated by the Columbia Transportation Division of the Oglebay Norton Company.
S.S. Edmund Fitzgerald Hull 301
200 ft. long mid section found destroyed
S.S. Edmund Fitzgerald Hull 301
4,000 ft of cracking was detected in the keelson and frames
Some 4,000 ft. of cracking was detected in the keelson and frame connection to the shell plating; however, during the winter layup of 1968-1969, this condition was look at and a minimum redesign and repair was done to get a coast guard approval to get the boat back in service that year. Each year the cracking came back.The mud layer in the bottom of the ballast tanks would make it hard to inspect for this problem each year.
October 1956 - Hull 301
Speed of Sound from the stern break to pilot house
The speed of sound is dependent on the density of the air. The density of the air is dependent on the temperature of the air.
The FITZGERALD was a conventional "straightdecker" Great Lakes bulk cargo vessel. It was 729 feet long, 75 feet in breadth, 39 feet in depth. There were 21 cargo hatch openings. Each opening measured 11 feet longitudinally and 48 feet transversely and had a 24-inch coaming above the weather deck.
The Edmund Fitzgerald wreck hull shows two breaks -
Stern break left 253 ft. intack and the Bow break left 276 ft. intack with the Center 200 ft. section destroyed.
The center section destroyed was 200 ft long X 75 ft. wide X 39 ft. tall, made of steel.
Edmund Fitzgerald 729 ft long - The Stern break broke 253 ft. from the back -
The Captain Location was 35ft. from the point at the Bow.
The pilot house crew was 441 ft away from the stern break @ 40 degrees Fahrenheit = 0.4023 second for the sound of the hull break to travel and be heard by the pilot house crew.
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Air Temperature
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Speed of Sound
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70 degrees Fahrenheit
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1128.683 Feet per Second
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60 degrees Fahrenheit
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1117.977 Feet per Second
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50 degrees Fahrenheit
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1107.167 Feet per Second
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40 degrees Fahrenheit
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1096.251 Feet per Second
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Stern-Mounted Balanced Rudder - Symmetrical
(NACAOO)
CRA
Link to Infomation . Link to Information
Rudders are shaped so as to minimize hydrodynamic drag. A rudder operates by redirecting the fluid pasting the hull, thus imparting a turning motion to the boat.
The rudder and propeller was undamaged with the rudder position lock in at 10 degrees from centerline.This 10 degrees rudder position will turn the Fitz to Port while on a T125 heading for White Fish Bay. The Fitz broke up as the winds and waves were from the west puting heavy pressure on the Fitz weeken hull.
The white painted draft marks are 6" tall and 6" o.c. space apart.
The 19 ft. draft mark is center over a welded seam in the hull plate.
Note: 6" change in a draft mark = 810 Tons
The forward deckhouse contained the pilot house and accommodations for the deck crew.
S.S. Edmund Fitzgerald Hull 301
836 Steel was used on the building of the Edmund Fitzgerald
Loading was completed about 1415 on November 9. The chief mate informed dock personnel that the vessel’s final drafts were 27 feet 2 inches forward and 27 feet 6 inches aft. Drafts were taken after receipt of the taconite pellets and 50,013 gallons of No. 6 fuel oil, delivered by a barge which came alongside while the cargo was being loaded.
Great Lakes bulk carriers are loaded to have as little trim, heel, and midship deflection as possible. Cargo is distributed so that the vessel does not hog; however, 1 inch of sag is considered acceptable.
American Bureau of Shipping
1865 - 2010
The American Bureau of Shipping was officially recognized by the
United States government in the Merchant Marine Act of 1920. The legislation
required that, in work involving a classification organization, every governmental agency in the United States would turn to ABS.
LOAD LINE CERTIFICATES
A Load Line Certificate is issued on behalf of an
Administration to indicate that a vessel is capable of carrying
its intended cargo in a stable condition. The load line itself is a
hull mark that indicates the maximum draft to which a vessel
is permitted to safely load.
1973 - PRESQUE ISLE,
a tug-barge combination designed for Great Lakes Service,
is over 1,000 feet long.
1980
WORLD’S LARGEST MERCHANT SHIP CLASSED BY ABS
A1,504-foot tanker, the world’s
largest merchant ship, was built
to ABS class in 1980.
The growth in the size of vessels – tankers, bulk carriers and containerships alike – took
designers and classification societies into new territory for which there were no
empirical guidelines. Innovation led to the development of composite vessels such as
ore-bulk-oil (OBO) carriers; specialist roro car carriers; open hatch bulk carriers,
designed for the efficient carriage of forest products; and a host of other specialist
carriers. It marked the demise of the traditional general cargo ship that had been the mainstay of every shipping fleet.
Empirical - Relyins on or derived from observation or experiment.
ABS World Headquarters
ABS Plaza
16855 Northchase Drive
Houston, Texas 77060
USA
Tel:1-281-877-5800
Minimum Required Freeboard
3 ft. 3 1/4" Deeper than 1958 design
Long Ton = 2,240 lbs.
135 Tons = 302,400 lbs.
5,366.25 Tons = 12,020,400 lbs.
1969 Minimum required freeboard is reduced by the American Board of Shipping (ABS)
1971 Freeboard is again reduced by ABS
1973 Freeboard is again reduced by ABS. The S.S. Edmund Fitzgerald can now legally carry enough cargo to sit 3 feet 3 1/4 inches lower in the water than was considered safe when she was launched. (4,421.5 tons more.) The shipping industry standard for shipments of coal is the net ton (2,000 lbs or 907.2 kgs). Other bulk commodities use the gross ton (2,240 lbs / 1,016 kgs) or metric tonne (1,000 kgs / 2,204.6 lbs).
Note: The deeper the draft, the greater the changing loads to the boat
(Axial Stress - Bearing Stress - Compression Force - Creep - Flexure - Lateral Forces - Normal (axial) Stress - Stress - Stress Concentration - Tension Force - Thermal Force - Thermal Strain - Torsion Fatigue Stress (Repeated Low-Force Load - Overload Stress (High-Force Load) Load and Lifespan - Fluid Dynamics - Loading and Unloading Cargo)
Between 1958 and 1973, the FITZGERALD was permitted three reductions in the minimum freeboard required by 46 CFR Part 45. (Freeboard on the FITZGERALD was the distance from the maximum draft permitted to the weather deck at side.)
As part of the requirements for obtaining the freeboards assigned on September 13, 1973, all vents were to be at least 30 inches above the weather deck. However, under 46 CFR 45.133(b), the FITZGERALD was permitted to have ballast tank vents extending to only 18 inches above the weather deck because the 30-inch height interfered with handling cargo on the ship.
Some 4,000 ft. of cracking was detected in the keelson and frame connection to the shell plating; however, during the winter layup of 1968-1969, this condition was look at and a minimum redesign and repair was done to get a coast guard approval to get the boat back in service that year.
6" change in a draft mark = 810 Tons
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Date
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Midsummer
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Summer
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Intermediate
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Winter
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Originally assigned when vessel was built
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11 feet-10 3/4 inches
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12 feet-6 3/4 inches
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13 feet-6 3/4 inches
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14 feet- 9 1/4 inches
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3 July 69
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11 feet-4 1/2 inches
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12 feet-1/2 inch
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13 feet-3/4 inch
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14 feet-3 1/2 inches
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17 Sept 71
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11 feet-4 1/2 inches
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12 feet-1/2 inch
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13 feet-3/4 inch
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13 feet-2 inches
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13 Sept 73
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10 feet-5/12 inches
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11 feet-2 inches
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11 feet-2 inches
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11 feet-6 inches
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1958 design of freeboard (Winter 14'- 9 1/4") - (Winter 1973 11'- 6") = 3' - 3 1/4" deeper than 1958 freeboard
1" draft = 135 tons - 39' 1/4" = 5,366.25 tons or 12,020,400 lbs.
Thats = 1,346,284,800 balls of taconite pellets
Note: Deeper in the water = more stress on the weather deck.
The FITZGERALD was a conventional "straightdecker" Great Lakes bulk cargo vessel. It was 729 feet long, 75 feet in breadth, 39 feet in depth, 13,632 gross tons, and 8,686 net tons. There were 21 cargo hatch openings. Each opening measured 11 feet longitudinally and 48 feet transversely and had a 24-inch coaming above the weather deck.
Working Stress, Allowable Stress, and Factor of Safety
Stress is produced by forces
MEMORIES
M = Moment & F = Concentrated force on hull (N)
Working stress is defined as the actual stress of a material under a given loading. The maximum safe stress that a material can carry is termed as the allowable stress. The allowable stress should be limited to values not exceeding the proportional limit. However, since proportional limit is difficult to determine accurately, the allowable stress is taken as either the yield point or ultimate strength divided by a factor of safety. The ratio of this strength (ultimate or yield strength) to allowable strength is called the factor of safety.
Structural steels are normally ductile but become brittle at low temperatures.
Suppose that a metal specimen from the Edmund Fitzgerald be placed in tension-compression-testing machine. As the axial load is gradually increased in increments, the total elongation over the gauge length is measured at each increment of the load and this is continued until failure of the specimen takes place. Knowing the original cross-sectional area and length of the specimen, the normal stress and the strain can be obtained. The graph of these quantities with the stress along the y-axis and the strain along the x-axis is called the stress-strain diagram. The stress-strain diagram differs in form for various materials. The diagram shown below is that for a medium-carbon structural steel. Metallic engineering materials are classified as either ductile or brittle materials. A ductile material is one having relatively large tensile strains up to the point of rupture like structural steel and aluminum, whereas brittle materials has a relatively small strain up to the point of rupture like cast iron and concrete. An arbitrary strain of 0.05 mm/mm is frequently taken as the dividing line between these two classes.
Structural steels become brittle at low temperatures and there is a change in the mechanism of fracture. There is little deformation of the sample and the grains in the microstructure fail along certain crystal planes. This is known as cleavage.
Structural steels are normally ductile but become brittle at low temperatures. There is a lot of deformation of the sample and the grains in the microstructure fail by void formation as the metal flows around hard particles in the microstructure. This is known as microvoid coalesence.
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Brittle Fracture of Steel
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Ductile Fracture of Steel
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Hull 301 Edmund Fitzgerald November 29, 1957
About 20 sections of the Fitz bottom and deck top were build off site by other contractors
The S.S. Edmund Fitzgerald was built in one year. The winter was very cold and the boat was built outside.
Pre-heating can eliminate stresses in steel and eliminate or reduce the possibility of crack formation, heat distortion and shrinkage.
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Steel Groups
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Steel Designation
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% Carbon
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Preheat F
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Preheat C
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Plain Carbon
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Plain Carbon
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Below 0.20
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Up to 200 F
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Up to 93 C
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Plain Carbon
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Plain Carbon
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.20 to 0.30
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200-300 F
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93-140 C
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Plain Carbon
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Plain Carbon
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0.30 to 0.45
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300-500 F
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149-250 C
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Plain Carbon
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Plain Carbon
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0.45 to 0.80
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500-800 F
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260-426 C
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Steel is an alloy composed of iron and carbon--the higher the carbon content, the stronger, harder and more brittle the steel. There are many types of steel, all of which are categorized based upon various physical properties and carbon content. High carbon steel is very strong and it is used for files, cold chisels and various metal tools while low carbon steel is used for tubing, nails and castings.
Preheating the base metal before welding is an important defense against rapid cooling and can help reduce hydrogen levels; both are factors that can lead to cracking. The material to be preheated and its thickness determine the proper preheat temperature
Welding short, small fillet welds also can reduce heat input and overall residual stresses on the AR plate to help minimize cracking.
Kestner Clamps
Used on Great Lake vessels to secure there large hatch covers.
Another good weather day in NovemberEach hatch cover could be secured by 68 manually operated "Kestner" clamps arranged on 2-foot centers.12 Kestner clamps was used per hatch cover on good weather day to day runs, using two clamps at each corner and two in the middle of each long side. If loading was done on a weekend, the Monday shift would finish the clamping down to avoid any overtime pay from a weekend loading. The Fitz left Sunday November 9, 1975 at 2:15 PM in good weather and would have to pay company overtime if they didn't finish clamping all of the Kestner clamps on that weekend in good weather. The next day, the Fitz receipt of storm warnings at 2:00 AM.
On November 10, the storm was located over central Wisconsin, had a minimum barometric pressure of 29.24 inches of mercury and was moving at an average speed of 29 knots. At 0100 on November 10, the FITZGERALD was about 20 miles south of Isle Royal and reported winds from 030 T at 52 knots and waves of 10 feet.
The Fitz at 0200 reported that he must slow down to haft speed because the boat was working to hard in only 10 ft seas. The Fitz was steering 45d and turning haft speed at Royal Island. The Anderson just ahead of the Fitz was turning 85 rpm and was steering good.
VIDEO of the Trip
Calculated Water Weight
The Fitz was taking on water that cause a list
The Fitz was design at 135 tons per inch of reduction in freeboard
About 1530, the FITZGERALD, then in a position northeast of Caribou Island, called the ANDERSON and reported, "I have a fence rail down, have lost a couple of vents, and have a list." The FITZGERALD further advised that she would ‘‘check-down’’ to allow the ANDERSON to close the distance between the vessels. The ANDERSON asked the FITZGERALD if the pumps were going and the reply was, "Yes, both of them."
