Copyright USGenNet Inc., 2015 All Rights Reserved USGenNet Data Repository Please read USGenNet Copyright Statement on this page: Transcribed and submitted by Linda Talbott for the USGenNet Data Repository http://www.us-data.org/ =========================================================================== Formatted by USGenNet Data Repository Chief Archivist, Linda Talbott All of the above information must remain when copied or downloaded. =========================================================================== (note: while some formatting changes were necessary to transcribe this document the content remains entirely as written in the official report.) From: Marine Board of Investigation To: Commandant (G-MMI) Subj: S. S. EDMUND FITZGERALD, O. N. 277437; sinking in Lake Superior on 10 November 1975, with loss of life FINDINGS OF FACT (continued) ---------------- 12. Load Line and Stability ----------------------- The requirements for load lines on merchant vessels engaged in voyages on the Great Lakes are based upon the Coastwise Load Line Act, as modified by agreements between the U.S. and Canadian governments. A comparison of the load line requirements for Great Lakes vessels and those for vessels operating on the oceans shows that, for vessels of similar dimensions, the freeboard required for ocean service would be approximately the same. However, the longitudinal strength required for the Great Lakes vessel would be approximately one-half of that required for a vessel on an ocean voyage. FITZGERALD was built in 1958, and was issued a Load Line Certificate at that time. In 1967, a joint U. S. - Canadian committee undertook a reevaluation of the load line requirements for operation on the Great Lakes. This study 69 --------------------------------------------------------------------------- resulted in extensive changes to the Great Lakes Load Line Regulations. The first of these changes was published in 1969 as an addition to the Load Line Regulations, which allowed "Reduced Freeboards for Steamers Having Superior Design and Operational Features Engaged on Great Lakes Voyages." In 1971, the regulations were amended by reducing the "factor for winter season," with the result that the minimum freeboard allowed during the winter season, i.e., after 1 November, was reduced. Finally, in 1973, the Great Lakes Load Line Regulations were completely revised. These revised regulations have become known as the 1973 Great Lakes Load Line Regulations. The 1973 Great Lakes Load Line Regulations, which were in effect and applied to FITZGERALD at the time of the casualty, include requirements involving watertight integrity above the Freeboard Deck, details of hatch covers and doors, strength of superstructures, details of air pipes, ventilators, scuttles and manholes, and protection for the crew. Under the 1973 Great Lakes Load Line Regulations, for vessels with a length in excess of 500 ft. greater length does not require a proportionally greater required freeboard. Also, under the 1973 Great Lakes Load Line Regulations, the winter penalty for Great Lakes Load Lines was reduced to be no greater than the winter penalty for a vessel operating on the oceans. The following table shows the load lines assigned to FITZGERALD. 70 --------------------------------------------------------------------------- Minimum Required Freeboard -------------------------- Date Mid-Summer Summer Intermediate Winter ---- ---------- ------ ------------ ------ Originally 11'10-3/4" 12'6-3/4" 13'6-3/4" 14'9-1/4" assigned when vessel was built 3 July 11'4-1/2" 12'0-1/2" 13'0-3/4" 14'3-1/2" 1969 17 Sept 11'4-1/2" 12'0-1/2" 13'0-3/4" 13'2" 1971 13 Sept 10'5-1/2" 11'2" 11'2" 11'6" 1973 Before the 1973 load line was issued, minor modifications of the vessel were required. These included modification of watertight doors by adding stiffeners and deadlight covers, installing an additional course of railing on the Forecastle deck and Poop deck, increasing the freeing port area aft, increasing the height of the tunnel vents and installing covers on the windlass room chocks. Under the 1973 Load Line Regulations, Midsummer load lines applied May 1 through September 15, Summer load lines applied April 16 through April 30 and September 16 through September 30, Intermediate load lines apply October 1 through October 31 and April 1 through April 15 and Winter load lines apply November 1 through March 31. Thus, the Winter load line applied to FITZGER- ALD at the time of her last loading. The last Load Line Certificate for FITZGERALD was issued by the American Bureau of Shipping at New York City on 1 July 1974. 71 --------------------------------------------------------------------------- The last Load Line Survey was conducted in connection with the American Bureau of Shipping annual survey in Toledo, OH, on 9 April 1975. One of the significant changes included in the 1973 Great Lakes Load Line Regulations was the requirement that a vessel must have on board, in a form approved by the Commandant of the Coast Guard, sufficient information to: (a) Enable the Master to load and ballast the vessel in a manner that avoids unacceptable stresses on the vessel's structure, and (b) Guide the Master as to the stability of the ship under varying conditions of service. The first of these established a new requirement for a Loading Manual. Before this, a Loading Manual had not been required on Great Lakes vessels. The regulations do not include particulars on what should be included in the Loading Manual. Testimony of Coast Guard naval architects indicated that it should include information on all normal cargo and ballast loading conditions, instructions on how to ballast and deballast the ship and information on the sequence of loading and unloading. Other testimony indicated that first attempts to develop Loading Manual for vessels operated by Oglebay-Norton Company included detailed theoretical analysis of the loading and unloading of vessels. These theoretical studies resulted in loading plans which varied markedly from those used in the practice of loading these ore carrying vessels. Experience with these earliest loading plans showed that the Mates in charge of the loading of the vessels strongly preferred the loading procedures which they had been using. These procedures were 72 --------------------------------------------------------------------------- analyzed by a naval architect employed by the operators of the vessels, and it was found that only small modifications were necessary to insure that stresses of the vessels as loaded were within acceptable limits. Based upon this analysis, the actual procedures were used to develop a new loading manual for FITZGER- ALD. This Manual was approved by the American Bureau of Shipping on 17 October 1973 and by the Coast Guard on 23 October 1973. A detailed analysis of this Loading Manual for FITZGERALD shows: a. The Manual contains information relating to the total load for each hatch, but there is no information provided on intermediate loads within the loading sequence or on any aspect of unloading. b. The Manual was prepared for the two-belt loading system used at Silver Bay, MN, FITZGERALD's normal poiont of loading. It does not contain information directly applicable to a chute dock, such as the one at which FITZGERALD loaded on 9 November. c. The Manual does not contain information on ballasting or beballasting or on fueling. d. The Manual does not contain information on calculation of Stress Numeral. Stability requirements for Great Lakes ore carriers of the straight deck type, such as FITZGERALD (i.e., not equipped with unloading machinery), are the same as those for ocean-going vessels; the Master of the vessel must be furnished with suffi- cient stability information to allow him, for any condition of loading, to obtain accurate guidance as to the stability of the 73 --------------------------------------------------------------------------- vessel. However, detailed studies have indicated that the typical Great Lakes ore carrier has a very high level of inher- ent stability because the cargo is dense (with a stowage factor of 10 to 18 cubic feet per ton), it is carried low in the vessel and there is little free surface effect from the ballast tanks (the width of the upper portion of the tanks is small compared to the beam of the vessel). Because of this high level of in- herent stability, it has been determined by the Coast Guard that neither stability tests nor stability calculations are required for vessels of this type. Accordingly, no inclining experiment had ever been performed on FITZGERALD, and no sta- bility calculations were available. Coast Guard regulations do not require general service cargo ships, operating on the ocean or on the Great Lakes, to meet any damage stability standard. Accordingly, FITZGERALD had not been subjected to a damage stability assessment. The Great Lakes Load Line Regulations require that when an air pipe to any tank extends above the freeboard or superstruc- ture deck, it must be of steel and of substantial construction, have a permanently attached means of closing, and have a height, from the deck to a point where water may obtain access below deck, of at least 30 inches above the freeboard deck, 24 inches above raised quarter decks and 12 inches above other superstruc- ture decks. However, the regulations also state that if this height ". . . interferes with working the ship, the Commandant may approve a lower height after considering the closing arrange- ments." Such approval had been granted in the case of the ballast tank vents on FITZGERALD, which, including the mushroom cap, extended only 18 in. above the spar deck. The vents for the fore and aft tunnels, located forward and aft on the Spar Deck, were of the same 8-inch pipe as the ballast tank vents, and had simi- lar mushroom closures. The tunnel vents had been raised to 30 inches above the deck as part of the September 1973 load line assignment. 74 ===========================================================================