NTSB Accident Report - November 10,1975
About 1915 EST., on November 10, 1975, the Great
Lakes bulk cargo vessel SS EDMUND FITZGERALD, fully loaded with a cargo of
taconite pellets, sank in eastern Lake Superior in position 46 59.91 N, 85
06.6’W, approximately 17 miles from the entrance to Whitefish Bay,
Michigan. The ship was en route from Superior, WI, to Detroit, MI, and had been
proceeding at a reduced speed in a severe storm. All the vessel’s 29
officers and crewmembers are missing and presumed dead. No distress call was
heard by vessels or shore stations.
The Safety Board considered many factors during the investigation including stability, hull strength, operating practices, adequacy of weathertight closures, hatch cover strength, possible grounding, vessel design, loading practices, and weather forecasting.
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-weathertight 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 weathertight 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
The Safety Board considered many factors during the investigation including stability, hull strength, operating practices, adequacy of weathertight closures, hatch cover strength, possible grounding, vessel design, loading practices, and weather forecasting.
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-weathertight 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 weathertight 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
THE
ACCIDENT:
About 0830 (all times are Eastern Standard based on the 24-hour clock) on November 9, 1975, the SS EDMUND FITZGERALD began loading 26,116 long tons of taconite pellets at Burlington Northern Railroad Dock No. 1 in Superior, WI. This pier, known as a "chute pier," is equipped with built-in storage bins, known as "pockets," which are usually filled before a vessel arrives. Chutes are lowered from each "pocket" to direct the cargo into the hatches of the vessel. Most of the "pockets" are filled with 300 tons of taconite pellets; however, a few pockets are filled with 100 tons or 200 tons. These smaller amounts of cargo are used during the final phase of loading to trim the ship for departure.
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.
Neither shipboard nor dock personnel experienced difficulties while loading the cargo nor was any difficulty or damage reported by the crew of the FITZGERALD. Shore side personnel saw the ship’s crew replacing the hatch covers after loading.
Upon departure at 1415, the FITZGERALD proceeded at full speed of 99 rpm, approximately 16.3 mph. About 1630, the SS ARTHUR M. ANDERSON departed Two Harbors, Minnesota, with a similar cargo en route to Gary, Indiana. Separated by 10 to 20 miles, the two vessels proceeded on similar courses across Lake Superior.
Because of predicted deteriorating weather, the receipt of storm warnings at 0200 on November 10, and discussions by radiotelephone, the FITZGERALD and ANDERSON departed the recommended shipping lanes along the southern shore of Lake Superior, and proceeded northeastward south of Isle Royal, then eastward along the northern shore, and then southeastward along the eastern shore. This departure from the recommended track allowed the two vessels to take advantage of the lee provided by the Canadian shore. This is a generally accepted practice among Great Lakes mariners to avoid adverse sea conditions during fall and winter storms when the wind direction makes this lee available. During the first 10 to 11 hours of the voyage, the ANDERSON was ahead of the FITZGERALD; however, about 0300 on November 10, the faster FITZGERALD pulled slightly ahead.
The FITZGERALD made routine weather reports at 0100 and 0700 on November 10. In the normal morning report to the company office, the FITZGERALD said her estimated time of arrival at Sault Ste. Marie was indefinite because of bad weather.
As the FITZGERALD and the ANDERSON approached the eastern shore, the FITZGERALD proceeded farther east than the ANDERSON before changing to a southeasterly course toward Michipicoten Island. Since the FITZGERALD traveled a greater distance at a higher speed, the distance between the two vessels remained almost constant. About 1252, the ANDERSON was abeam Otter Island at a range of 10.8 miles, and the FITZGERALD was 8 miles ahead and slightly east of the ANDERSON’s track. (See figure 1.) At that point, the FITZGERALD was about 17 miles north-northwest of Michipicoten Island.
At 1350, the ANDERSON changed course to 230 degrees T to allow more sea room west of Michipicoten Island because the wind was predicted to haul to the northwest. At this time, the FITZGERALD was 2 1/2 to 3 miles southwest of Michipicoten Island, and she advised the ANDERSON that she would "continue on" although she was "rolling some." The FITZGERALD continued southeastward toward Whitefish Point on a course of 1410 T while the ANDERSON proceeded southwestward to about 11 miles west of Michipicoten Island and changed course to 130 degrees T at 1445. At this time, the FITZGERALD was observed to be about 16 miles ahead, a position 9 miles south of Michipicoten Island. At 1520, the ANDERSON changed course to 125 degreees T at a position 7.7 miles southwest of Michipicoten Island. The FITZGERALD was 16 miles ahead and slightly to the right of the ANDERSON’s trackline.
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."
About 1610, the FITZGERALD advised the ANDERSON that both her radars were inoperative and asked that the ANDERSON keep track of the FITZGERALD and provide navigational assistance. At 1634, the ANDERSON changed course to 141 degrees T in a position 7.5 miles, 035 degrees T from the north end of Caribou Island and observed the FITZGERALD 14 to 15 miles ahead and slightly to the right of the ANDERSON’s heading flasher. At 1728, the ANDERSON fixed her position 10.5 miles east of Caribou Light, determined that the FITZGERALD was 15 miles ahead and slightly left (east) of the ANDERSON’s heading flasher, and advised the FITZGERALD that Whitefish Point was 35 miles from the FITZGERALD on a bearing of 144 degrees T. The FITZGERALD replied that she "wanted to be 2 1/2 miles off Whitefish Point," and appeared to be steering for that position.
About 1639, the Coast Guard station at Grand Marais, MI, advised the FITZGERALD, in response to her inquiry, that the radio beacon at Whitefish Point was not operating.
Between 1700 and 1730, a Great Lakes registered pilot on board the northbound Swedish vessel AVAFORS, in a position near Whitefish Point, answered a call from the FITZGERALD and said that Whitefish Point Light was operating but that the radio beacon was still off. During a radiotelephone conversation between the two vessels, the master of the FITZGERALD apparently spoke to personnel aboard the FITZGERALD while the radiotelephone remained on the transmit mode. The master was overheard saying, "Don’t allow nobody on deck," followed by some conversation concerning a vent, which was not understood aboard the AVAFORS. The master advised the AVAFORS that the FITZGERALD had a "bad list," had lost both radars, and was taking heavy seas over the deck in one of the worst seas he had ever encountered.
About 1820, the ANDERSON advised the FITZGERALD that the FITZGERALD was working to the left of the ANDERSON’s heading of 1420 T and determined by radiotelephone that the FITZGERALD was steering 141 degrees T.
At 1900, the ANDERSON advised the FITZGERALD that she was 10 miles ahead and 1 to 1 1/2 miles to the left (east) of the ANDERSON’s heading flasher. At 1910, 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 radiotelephone conversation with the FITZGERALD. 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.
Between 1920 and 2030, the ANDERSON tried calling the FITZGERALD on VHF-FM radiotelephone, but got no response. At 2032, the ANDERSON notified the Coast Guard that the FITZGERALD may have suffered a casualty.
Wreckage identified as that of the FITZGERALD was located in position 46 59.91 N’, 85 06.6’ W in 530 feet of water in eastern Lake Superior just north of the International Boundary in Canadian waters. This position correlates with the last position of the FITZGERALD as reported by the ANDERSON.
Crew Information
The crew of the FITZGERALD consisted of the following 29 persons: a master, 3 licensed deck officers, a chief engineer, 4 licensed engineering officers, and 20 unlicensed personnel. No survivors were found and no bodies were recovered.
The master and chief mate were experienced Great Lakes mariners, having been licensed since 1938 and 1941, respectively. Both men held valid licenses as Master and First Class Pilot for Great Lake vessels of any gross tonnage. The other mates held valid licenses as First Class Pilot for Great Lakes vessels of any gross tonnage which were first issued in 1969 and 1973, respectively. The engineering officers were similarly experienced.
The master had been employed by the vessel’s operator since 1938, had been employed as master since 1951, and had served as master of the FITZGERALD since April 1972.
The chief mate had been employed by the vessel’s operator since 1947 in various capacities, including relief master in 1966 and 1971,’ and had served aboard the FITZGERALD as chief mate since April 1975.
Vessel Information
The FITZGERALD was one of a fleet of 14 to 18 vessels operated by the Columbia Transportation Division between 1972 and 1977. The Coast Guard casualty records for the company fleet did not reveal any heavy weather damage during this period.
The FITZGERALD was a conventional "straightdecker" Great Lakes bulk cargo vessel. (See figure 2.) 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.
The vessel had a 860,950-cubic-foot cargo hold divided by two nonwatertight transverse "screen" bulkheads. Outboard and below the cargo hold were eight ballast tanks divided at the centerline into port and starboard tanks. (See figure 2.) The forward deckhouse contained the pilot house and accommodations for the deck crew. The engine room was located aft, above which were the rest of the accommodations and the crew’s messing facilities. Below the weather deck and above the ballast tanks were two tunnels, one port and one starboard, used for access between the accommodation areas during adverse weather. The sheer strake extended 15 3/8 inches above the weather deck at side and was connected to the stringer plate by a riveted gunwale bar.
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. Each opening was made weathertight by a single-piece steel hatch cover. The hatch covers were made of 5/16-inch stiffened plate with a 9/16-inch rubber gasket around the underside of the plate’s perimeter. Each hatch cover was secured by 68 manually operated "Kestner" clamps arranged on 2-foot centers. Each clamp had an adjustment bolt which determined the force applied by the individual clamp and therefore controlled the deflection of the hatch cover, the compression of the rubber gasket, and the weathertightness of the hatch opening. There were no written procedures concerning maintenance or adjustment of the hatch clamps or gaskets. An electrically operated hatch cover crane which ran on rails outboard of the cargo hatch openings was used for lifting the hatch covers.
Access to the cargo hold was provided through two 30-inch hatches through the weather deck located at the "screen" bulkheads fitted on 24-inch coamings, through doors from the tunnels, and through doors at the main deck level (i.e., the deck level below the weather deck) at the forward and after ends of the cargo hold.
Two 8-inch-diameter vent pipes which extended 18 inches above the weather deck were fitted for each ballast tank. The port and starboard access tunnels had similar vents extending 30 inches above the weather deck located forward and aft. In addition, each ballast tank was fitted with a remote water level indicator device, called a "King Gage," located in the lower engineroom near the ballast pumps. The only means of detecting water in the cargo hold or access tunnel was by visual inspection. Federal regulations do not require that Great Lakes vessels be equipped with instruments to indicate trim or list.
The bilge and ballast system consisted of a piping system connected through manifolds and valving to four 7,000 gallon-per-minute main pumps and two 2,000 gallon-per-minute auxiliary pumps. The ballast system could be used to de-water the cargo hold through two suctions located at the aftermost end of the No. 3 cargo hold, port and starboard. The tunnels could be drained by manually operated drains connected to the ballast tanks.
The following radiotelephone equipment was located in the pilothouse and chartroom: Two VHF-FM, 12-channel, 25-watt radiotelephones operated from vessel’s power; one VHF-FM 12-channel, 25-watt radiotelephone operated from rechargable batteries located in the pilothouse; one AM, 8-channel, 100-watt radiotelephone operated from vessel’s power; one AM, emergency, 50-watt radiotelephone including channel 51 (2182 kHz), operated from rechargeable batteries. The FITZGERALD also had a radio direction finder and two surface scan radar sets. No fathometer was required and none was installed.
After her delivery in 1958, the FITZGERALD operated essentially unchanged until 1969 when a diesel-powered bow thruster was installed. During the winter of 1971-1972, the main propulsion plant was converted from coal to oil and the coal bunkers were converted to fuel oil tanks. An automatic boiler combustion and feed-water control system was installed as part of this conversion.
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.) A comparison of the requirements for Great Lakes cargo vessels and those for vessels operating on the oceans shows that for vessels of similar dimensions, the freeboard required for a Great Lakes Load Line and that required for ocean service would be approximately the same. However, the longitudinal strength required for a Great Lakes vessel is approximately one—half that required for a vessel in ocean service.
About 0830 (all times are Eastern Standard based on the 24-hour clock) on November 9, 1975, the SS EDMUND FITZGERALD began loading 26,116 long tons of taconite pellets at Burlington Northern Railroad Dock No. 1 in Superior, WI. This pier, known as a "chute pier," is equipped with built-in storage bins, known as "pockets," which are usually filled before a vessel arrives. Chutes are lowered from each "pocket" to direct the cargo into the hatches of the vessel. Most of the "pockets" are filled with 300 tons of taconite pellets; however, a few pockets are filled with 100 tons or 200 tons. These smaller amounts of cargo are used during the final phase of loading to trim the ship for departure.
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.
Neither shipboard nor dock personnel experienced difficulties while loading the cargo nor was any difficulty or damage reported by the crew of the FITZGERALD. Shore side personnel saw the ship’s crew replacing the hatch covers after loading.
Upon departure at 1415, the FITZGERALD proceeded at full speed of 99 rpm, approximately 16.3 mph. About 1630, the SS ARTHUR M. ANDERSON departed Two Harbors, Minnesota, with a similar cargo en route to Gary, Indiana. Separated by 10 to 20 miles, the two vessels proceeded on similar courses across Lake Superior.
Because of predicted deteriorating weather, the receipt of storm warnings at 0200 on November 10, and discussions by radiotelephone, the FITZGERALD and ANDERSON departed the recommended shipping lanes along the southern shore of Lake Superior, and proceeded northeastward south of Isle Royal, then eastward along the northern shore, and then southeastward along the eastern shore. This departure from the recommended track allowed the two vessels to take advantage of the lee provided by the Canadian shore. This is a generally accepted practice among Great Lakes mariners to avoid adverse sea conditions during fall and winter storms when the wind direction makes this lee available. During the first 10 to 11 hours of the voyage, the ANDERSON was ahead of the FITZGERALD; however, about 0300 on November 10, the faster FITZGERALD pulled slightly ahead.
The FITZGERALD made routine weather reports at 0100 and 0700 on November 10. In the normal morning report to the company office, the FITZGERALD said her estimated time of arrival at Sault Ste. Marie was indefinite because of bad weather.
As the FITZGERALD and the ANDERSON approached the eastern shore, the FITZGERALD proceeded farther east than the ANDERSON before changing to a southeasterly course toward Michipicoten Island. Since the FITZGERALD traveled a greater distance at a higher speed, the distance between the two vessels remained almost constant. About 1252, the ANDERSON was abeam Otter Island at a range of 10.8 miles, and the FITZGERALD was 8 miles ahead and slightly east of the ANDERSON’s track. (See figure 1.) At that point, the FITZGERALD was about 17 miles north-northwest of Michipicoten Island.
At 1350, the ANDERSON changed course to 230 degrees T to allow more sea room west of Michipicoten Island because the wind was predicted to haul to the northwest. At this time, the FITZGERALD was 2 1/2 to 3 miles southwest of Michipicoten Island, and she advised the ANDERSON that she would "continue on" although she was "rolling some." The FITZGERALD continued southeastward toward Whitefish Point on a course of 1410 T while the ANDERSON proceeded southwestward to about 11 miles west of Michipicoten Island and changed course to 130 degrees T at 1445. At this time, the FITZGERALD was observed to be about 16 miles ahead, a position 9 miles south of Michipicoten Island. At 1520, the ANDERSON changed course to 125 degreees T at a position 7.7 miles southwest of Michipicoten Island. The FITZGERALD was 16 miles ahead and slightly to the right of the ANDERSON’s trackline.
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."
About 1610, the FITZGERALD advised the ANDERSON that both her radars were inoperative and asked that the ANDERSON keep track of the FITZGERALD and provide navigational assistance. At 1634, the ANDERSON changed course to 141 degrees T in a position 7.5 miles, 035 degrees T from the north end of Caribou Island and observed the FITZGERALD 14 to 15 miles ahead and slightly to the right of the ANDERSON’s heading flasher. At 1728, the ANDERSON fixed her position 10.5 miles east of Caribou Light, determined that the FITZGERALD was 15 miles ahead and slightly left (east) of the ANDERSON’s heading flasher, and advised the FITZGERALD that Whitefish Point was 35 miles from the FITZGERALD on a bearing of 144 degrees T. The FITZGERALD replied that she "wanted to be 2 1/2 miles off Whitefish Point," and appeared to be steering for that position.
About 1639, the Coast Guard station at Grand Marais, MI, advised the FITZGERALD, in response to her inquiry, that the radio beacon at Whitefish Point was not operating.
Between 1700 and 1730, a Great Lakes registered pilot on board the northbound Swedish vessel AVAFORS, in a position near Whitefish Point, answered a call from the FITZGERALD and said that Whitefish Point Light was operating but that the radio beacon was still off. During a radiotelephone conversation between the two vessels, the master of the FITZGERALD apparently spoke to personnel aboard the FITZGERALD while the radiotelephone remained on the transmit mode. The master was overheard saying, "Don’t allow nobody on deck," followed by some conversation concerning a vent, which was not understood aboard the AVAFORS. The master advised the AVAFORS that the FITZGERALD had a "bad list," had lost both radars, and was taking heavy seas over the deck in one of the worst seas he had ever encountered.
About 1820, the ANDERSON advised the FITZGERALD that the FITZGERALD was working to the left of the ANDERSON’s heading of 1420 T and determined by radiotelephone that the FITZGERALD was steering 141 degrees T.
At 1900, the ANDERSON advised the FITZGERALD that she was 10 miles ahead and 1 to 1 1/2 miles to the left (east) of the ANDERSON’s heading flasher. At 1910, 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 radiotelephone conversation with the FITZGERALD. 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.
Between 1920 and 2030, the ANDERSON tried calling the FITZGERALD on VHF-FM radiotelephone, but got no response. At 2032, the ANDERSON notified the Coast Guard that the FITZGERALD may have suffered a casualty.
Wreckage identified as that of the FITZGERALD was located in position 46 59.91 N’, 85 06.6’ W in 530 feet of water in eastern Lake Superior just north of the International Boundary in Canadian waters. This position correlates with the last position of the FITZGERALD as reported by the ANDERSON.
Crew Information
The crew of the FITZGERALD consisted of the following 29 persons: a master, 3 licensed deck officers, a chief engineer, 4 licensed engineering officers, and 20 unlicensed personnel. No survivors were found and no bodies were recovered.
The master and chief mate were experienced Great Lakes mariners, having been licensed since 1938 and 1941, respectively. Both men held valid licenses as Master and First Class Pilot for Great Lake vessels of any gross tonnage. The other mates held valid licenses as First Class Pilot for Great Lakes vessels of any gross tonnage which were first issued in 1969 and 1973, respectively. The engineering officers were similarly experienced.
The master had been employed by the vessel’s operator since 1938, had been employed as master since 1951, and had served as master of the FITZGERALD since April 1972.
The chief mate had been employed by the vessel’s operator since 1947 in various capacities, including relief master in 1966 and 1971,’ and had served aboard the FITZGERALD as chief mate since April 1975.
Vessel Information
The FITZGERALD was one of a fleet of 14 to 18 vessels operated by the Columbia Transportation Division between 1972 and 1977. The Coast Guard casualty records for the company fleet did not reveal any heavy weather damage during this period.
The FITZGERALD was a conventional "straightdecker" Great Lakes bulk cargo vessel. (See figure 2.) 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.
The vessel had a 860,950-cubic-foot cargo hold divided by two nonwatertight transverse "screen" bulkheads. Outboard and below the cargo hold were eight ballast tanks divided at the centerline into port and starboard tanks. (See figure 2.) The forward deckhouse contained the pilot house and accommodations for the deck crew. The engine room was located aft, above which were the rest of the accommodations and the crew’s messing facilities. Below the weather deck and above the ballast tanks were two tunnels, one port and one starboard, used for access between the accommodation areas during adverse weather. The sheer strake extended 15 3/8 inches above the weather deck at side and was connected to the stringer plate by a riveted gunwale bar.
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. Each opening was made weathertight by a single-piece steel hatch cover. The hatch covers were made of 5/16-inch stiffened plate with a 9/16-inch rubber gasket around the underside of the plate’s perimeter. Each hatch cover was secured by 68 manually operated "Kestner" clamps arranged on 2-foot centers. Each clamp had an adjustment bolt which determined the force applied by the individual clamp and therefore controlled the deflection of the hatch cover, the compression of the rubber gasket, and the weathertightness of the hatch opening. There were no written procedures concerning maintenance or adjustment of the hatch clamps or gaskets. An electrically operated hatch cover crane which ran on rails outboard of the cargo hatch openings was used for lifting the hatch covers.
Access to the cargo hold was provided through two 30-inch hatches through the weather deck located at the "screen" bulkheads fitted on 24-inch coamings, through doors from the tunnels, and through doors at the main deck level (i.e., the deck level below the weather deck) at the forward and after ends of the cargo hold.
Two 8-inch-diameter vent pipes which extended 18 inches above the weather deck were fitted for each ballast tank. The port and starboard access tunnels had similar vents extending 30 inches above the weather deck located forward and aft. In addition, each ballast tank was fitted with a remote water level indicator device, called a "King Gage," located in the lower engineroom near the ballast pumps. The only means of detecting water in the cargo hold or access tunnel was by visual inspection. Federal regulations do not require that Great Lakes vessels be equipped with instruments to indicate trim or list.
The bilge and ballast system consisted of a piping system connected through manifolds and valving to four 7,000 gallon-per-minute main pumps and two 2,000 gallon-per-minute auxiliary pumps. The ballast system could be used to de-water the cargo hold through two suctions located at the aftermost end of the No. 3 cargo hold, port and starboard. The tunnels could be drained by manually operated drains connected to the ballast tanks.
The following radiotelephone equipment was located in the pilothouse and chartroom: Two VHF-FM, 12-channel, 25-watt radiotelephones operated from vessel’s power; one VHF-FM 12-channel, 25-watt radiotelephone operated from rechargable batteries located in the pilothouse; one AM, 8-channel, 100-watt radiotelephone operated from vessel’s power; one AM, emergency, 50-watt radiotelephone including channel 51 (2182 kHz), operated from rechargeable batteries. The FITZGERALD also had a radio direction finder and two surface scan radar sets. No fathometer was required and none was installed.
After her delivery in 1958, the FITZGERALD operated essentially unchanged until 1969 when a diesel-powered bow thruster was installed. During the winter of 1971-1972, the main propulsion plant was converted from coal to oil and the coal bunkers were converted to fuel oil tanks. An automatic boiler combustion and feed-water control system was installed as part of this conversion.
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.) A comparison of the requirements for Great Lakes cargo vessels and those for vessels operating on the oceans shows that for vessels of similar dimensions, the freeboard required for a Great Lakes Load Line and that required for ocean service would be approximately the same. However, the longitudinal strength required for a Great Lakes vessel is approximately one—half that required for a vessel in ocean service.
Posted: Tue - December 7, 2004 at 06:41 PM
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Published On: Dec 07, 2004 06:44 PM
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