Historically, drydocks were concrete bays that had a gate at one end. A ship would float in, the gate would be closed and the bay would be pumped dry. They were called graving yards because originally that is where old wooden boats would be taken apart for the lumber.
For smaller boats, floating drydocks were developed. The drydock ballast tanks are flooded so that a boat can float into it. Then the water is pumped out of the ballast tanks so that it floats and raises the boat out of the water.
And floating drydocks grew to handle ships.
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Marine Video posted
USS ABSD-6 🚢
The advanced base sectional dock used as a floating dry dock by the US Navy, repairing USS South Dakota at Apra Harbor at Guam. South Dakota was in need of drydock repairs after an accidental explosion on 6 May 1945 while She was rearming from USS Wrangell.
Donald Soper: She wasn’t docked because of the explosion. “The battleship’s orders directed her to sail to Guam for inspection and repairs of her shafts and strut bearings to determine the cause of excessive vibration at high speeds, especially when she made 23 knots and used 10° or more left rudder”. The vibration was severe enough to disable radar and optical tracking systems in the superstructure. For details about the explosion and vibration issues, see
https://www.history.navy.mil/research/histories/ship-histories/danfs/s/south-dakota-ii--bb-57--chapter-3-19451969.html |
This is in Oct 2023 because the museum ship is being refurbished.
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Steven Proto posted
Battleship Texas in dry dock. |
Or sometimes you can tip the ship to expose what needs to be worked on. I have seen a photo of a Great Lakes freighter tilted so that they could do emergency repairs to the bow thruster. But that photo got uploaded to the city in which it took place. And I now can't remember where that was. But here is another photo.
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Stu Mac posted
The VLCC S/R LONG BEACH, 211k DWT. Tipped aft using internal ballasting, in San Francisco Bay. USCG/Class approved and safely performed so that a fwd, in-hull transducer box could be worked on from a workboat. Sure beat having to go to a large drydock!
Nyall Gonsalves: What would cause ‘damage’ to in hull transducer box? Are they under or on the side of these tankers?
Stu Mac: Nyall Gonsalves , Located on bottom. Can’t recall if it was water ingress or problems with the transducer electronics. This procedure was/is performed on numerous ships. Sometimes also tipped down by the head so that the prop, rudder, shaft seals, etc could be maintained or repaired.
Charles Brown: How is that not gonna bend the keel though?
Stu Mac: Charles Brown , Stresses all pre-calculated by computer and with experience and managed safely with ballasting, while also monitoring weather, tides, currents, etc. Actually far less overall static longitudinal stress than some of what she or other ships might encounter in very dynamic fashion during severe storms at sea.
Bruce Harsch: Odd not to to see a Bulbous bow. |
Roger Stutler
posted two photos with the comment: "M/V bilson in drydock."
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| 1, cropped |
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| 2, cropped |
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Dave Gust posted
Newt Marine Service based out of Dubuque, IA is looking for an experienced marine mechanic to help service and maintain our fleet of tow boats. Check out www.newtmarine.com or message me for more details. *I'm not a recruiter, I work for Newt Marine. |
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[Lost the reference]
"Newt Marine offers an extensive line of dry docking and ship repair services. We have two drydocks, with 60 feet between the wing-walls and a capacity of over 600 gross TN, we can handle most vessels." |
Large floating drydocks made it easier for the Navy to project its power across the Pacific Ocean.
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MilitaryPhotoDepot posted
USS Wisconsin BB-64 taken in AFDB-1, at Apra Harbor, Guam, 5 April 1952. NHHC Image
David Dryer: Iowa Class Battleships [Then that drydock can hold the biggest battleships that the US built.]
Frederick Selstrom: The drydocks came apart to fit through the Panama canal .
[Several comments imply this was AFDM-8.] |
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Alexandre Salgueiro posted
USS MISSOURI (BB-63) undergoing modernisation in the 80’s.
Brandon Hopkins: I've seen other sources that claim that this is when she was being maintained in 2009-2010 in Pearl Harbor. Note the guys in Hawaiian shirts, also how low the black line is painted since it's not got its full displacement as a museum ship and doesn't sit as low in the water. The cranes also match some video i've seen.
Either way, it's always amazing how big they look when they're in drydock.
Greg Moyer: My home from 86-89 as a BT. This picture was taken in Hawaii when she became a museum. I think 09 or 2010 |
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MilitaryPhotoDepot posted
12/28/1944 USS Iowa (BB-61) entering and inside floating dry-dock ABSD-2, 28 December 1944. USN Image |
Wisconsin, Missouri and Iowa are three of our four biggest battleships.
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