1) The document summarizes a marine survey of the USS North Carolina battleship that was conducted to assess its condition and develop a plan for repairs.
2) A cofferdam system was designed to allow repairs to hull plating between frames 5-37 while avoiding the large costs of dredging or moving the ship.
3) Individual cofferdam sections were installed to isolate repair areas, and hull plating was cut out and replaced with new steel plates in multiple areas along the side shell.
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U.S.S. North Carolina Survey & Repair, Patriots Point Presentation, 19 Oct. 2011
1. SURVEY & REPAIR OF BATTLESHIP U.S.S. NORTH CAROLINA Joseph Lombardi Marine Surveyor & Consultant Ocean Technical Services, LLC. 10 Dalton Avenue Gloucester, Massachusetts 01930
2. Vessel Data Designers: General Board Bureau of Construction & Repair (Hull) Bureau of Ordnance Bureau of Engineering Bureau of Yards & Docks The above bureaus later became the Bureau of Ships Hull Number: BB 55 Keel Laid: October 27, 1937 Launched: June 13, 1940 Commissioned: April 9, 1941 Decommissioned: June 27, 1947 Length: 728' " long Extreme Beam: 108 feet 3 7/8 inches wide Mean Draught: 油31 feet 7 inches normal, 35 feet 6 inches max. Displacement: 36,600 tons standard, 44,800 tons full load
3. Frame spacing: 4 centers Number of frames between perpendiculars: 178 遜 Tons per inch immersion: 121.5 tons Area of water plane: 55,080 sq. ft. Moment to alter trim one inch: 4,200 tons Moment to list one degree: 6,138 tons Total wetted surface: 98,730 sq. ft.油 Range of stability P/S (ship not damaged): 66.9 degrees 油 Inclination for maximum righting arm (ship not damaged): 34.3 degrees Complement: 油 2,339 (144 officers and 2,195 enlisted) Speed: 28 knots Armament: 9: 16-inch/45 caliber guns 20: 5-inch/38 caliber guns 60: 40mm/56 caliber guns 48: 20mm/70 caliber guns
4. Brooklyn Navy Yard NY. On building ways three days before launching, 11 June 1940. NARA (National Archives Record Administration).
5. Sliding down the building ways, as she is launched at the New York Navy Yard, 13 June 1940. Note the slope of her side armor, angled outward 15 degrees to increase its effective thickness against incoming enemy shells. USNHC # NH 44899.
12. North Carolina (BB-55) final fitting out and sea trials off New York Harbor Nov. Dec. 1941. Ship is about to launch observation plane from starboard catapult. USN / USNHC # NH 80988. Photo i.d. courtesy of Ron Smith.
14. On 6 September 1942, North Carolina (BB-55) maneuvered successfully, dodging a torpedo which passed 300 yards off the port beam. Nine days later, sailing with Hornet (CV-8), North Carolina took a torpedo portside, 20 feet below her waterline, and 6 of her men were killed. But skillful damage control by her crew and the excellence of her construction prevented disaster; a 5.6 degree list was righted in as many minutes, and she maintained her station in a formation at 26 knots. Portside damage from Japanese submarine I-15 torpedo (21-inch/oxygen propelled). Photo taken 11 Oct. 1942 at Pearl Harbor where permanent repairs were done.
15. Bow on shot, leaving Pearl Harbor upon completion of repairs. Notice paravane gear deployed off stem of ship
19. Task Group 38.3 enters Ulithi anchorage in column, 12 December 1944 while returning from strikes on targets in the Philippines. Ships are (from front): Langley (CVL-27); Ticonderoga (CV-14); Washington (BB-56); North Carolina (BB-55); South Dakota (BB-57); Santa Fe (CL-60); Biloxi (CL-80); Mobile (CL-63) and Oakland (CL-95). Official U.S. Navy Photograph # 80-G-301351 & HN-SD-97-00850 now in the collections of the National Archives.
20. The oiler U.S.S. Taluga (AO-62) refueling U.S.S. North Carolina (BB-55), Mar. 1945. LaVack picture courtesy of Tommy Trampp.
22. Post war in the Mothball Fleet, here inboard of sistership battleship U.S.S. WASHINGTON. Photo taken from topside hamper of battlecruiser U.S.S. GUAM at MOT Bayonne, NJ
23. The ship is being towed up the Cape Fear River to her final and present day berthing. The actual date of the photo is October, 1961, but it is not listed on the photo. As you can see on the photo, two 40mm quadruple mounts were removed before decommisioning, her catapults are gone. When she was decommissioned, she only carried her port catapult, the starboard one having been landed at her post-war refit at New York Navy Yard. Her aircraft crane at the stern was stored in its lowered position. The two original boat cranes, next to the aft stack, have been removed too. February, 1962 National Geographic Magazine.
24. Hull Survey Tasking included: 1.) Inspection of Topside Hamper including masts, weather decks and exterior hull, 2.) Interior spaces from armored citadel to and including all interior decks/spaces, turrets and engineering/machinery spaces; 3.) Tankage, as specified by Surveyor, was opened and vented by the Owner. 4.) Tankage inspected by Marine Chemist to 29 CFR & NFPA standards for Safe Entry prior to entry and then retested as required. 5.) Preparation of Survey Report with complete documentation of each space with embedded digital images, List of Recommendations for Repairs, inspection and recommendation of suitability of drydocks within limits of 3 day tow. Developed ROM costs analysis for towing and drydock repairs of vessel.
65. Ships Armor Belt Main Belt Armor: Extending from Frame 37 to Frame 147 from top of blister to 38 10 abobe M.B.L. Thickness between knuckle & top 12, thickness at bottom 6.6 S.T.S. Shell Plating: 30# S.T.S. in back of main belt armor 40# S.T.S. extending from top of main belt armor to maindeck armor to main deck
71. OTS Road Map for Ship Repairs 1.) Completed Hull Survey 2.) Analysis of location for ship repairs 3.) Completion of budgetary estimates 4.) Preparation of Ship Repair Specification 5.) Two rounds of RFQ pre-qualification for contrac- tors; Taylor Marine of Beaufort, NC chosen as prime contractor. 6.) Submittal and advertisement of RFP 7.) Opening bids & choosing Contractor 8.) Mobilization & Commencement of Repairs 9.) Complete Repairs & De-mobilize
72. Repair Methodology Leakage from Frame 5 to Frame 37, starboard side, Sheet pile cofferdam around bow/vessel with immense expense, dredging requirements, fraught with environmental permit issues. Solution determined by Surveyor was to design & build small cofferdam sized 30 long x 7 deep x 15 high. JMS Naval Architects & Salvage Engineers contracted to design cofferdam designed to be fitted against side shell plating. Cuts of 10high x 20 long permitted within cofferdam for the 遜 A-36 mild steel plating inserts. No doubler plating allowed.
106. Cofferdam Set #5, Track oxy-acetylene torch cutting cutting away top of blister fairing piece at rivet seam.
107. Project Summary Cofferdam very successful for waterline repairs. Immense cost savings over dredging & movement of ship to either Norfolk or Charleston for drydocking Installation of sheet pile cofferdam around all of vessel or bow area too costly and time con- suming given spawning & no dredge windows. Repairs to be completed ahead of time & on budget by Taylor Marine of Beaufort, NC near 1 st week of November 2011.