Since the weight of ballast required for the vessel to stay upright in afloat condition may be more than the weight acceptable by the keel block, it may be necessary to take the vessel into the dock with that much ballast and then de-ballast the vessel when she is inside the dry-dock but is still afloat. The original Kishorn Yard was developed as a manufacturing and fabrication yard for oil platforms in the 1970’s. And in the trench he built props of solid stone five cubits deep, and across them he laid beams crosswise, running the laces whole width of the trench, at four cubits' distance from one another; and then making a channel from the sea he filled all the space which he had excavated with water, out of which he easily brought the ship by the aid of whatever men happened to be at hand; then closing the entrance which had been originally made, he drained the water off again by means of engines (organois); and when this had been done the vessel rested securely on the before-mentioned cross-beams. This dry docking will only involve the requirements for satisfactory completion of the repairs for the under water damage.

To me this would be the the most sensible option, it’s close to HMB Portsmouth, its large enough to accommodate the vessels (I think it’s large enough for US carrier too) and surely its cheaper to recommission this rather than starting from scratch with a new dock? Yinson Production, part of Yinson Holdings, awarded a contract to the shipyard to modernise the Atlanta floating, production, storage and offloading (FPSO) vessel in May 2022. It is extremely important that supporting blocks conform to the structural members so that the ship is not damaged when its weight is supported by the blocks. This facility of adjusting the height is necessary because the ship’s bottom plate may not be exactly in a straight line (even a few millimeters of difference can result in overloading the hull structure and deforming the same and all classification rules allow certain tolerance in the straightness of the keel) and blocks of the same height can result in some portion of the hull not touching the blocks below that. The use of floating dry docks was reviewed early in these deliberations; however, they were rejected on infrastructure, security and access grounds.I am a happy new narrowboat owner, which I bought as a project and now looking for a dry dock to get it out of a water and get it inspected, repaired and re-coated. you could try charity dock on the Coventry at bedworth or grendon dock at grendon again on the Coventry. Where a ship is in dry-dock or on a slipway it is to be placed on blocks of sufficient height, and proper staging is to be erected as may be necessary, for the examination of the shell including bottom and bow plating, keel, stern, stern frame and rudder. Thus the extra weight of ballast, a minimum of which is required to be on board to provide stability when the vessel is afloat/sailing, has to be reduced to the maximum just before the vessel enters the dry-dock.

Dry docks used for building Navy vessels may occasionally be built with a roof, to prevent spy satellites from taking pictures of the dry dock and any vessels that may be in it. During World War II, fortified dry docks were used by the Germans to protect their submarines from Allied air raids (see submarine pen). For oil tankers (including ore/oil and ore/bulk/oil ships), chemical tankers and bulk carriers over 15 years of age the intermediate docking between Special Surveys is to be held in dry-dock. Southampton has nowhere near enough of the infrastructure needed in the vicinity of the KGV dock to support dry-docking and repair and regeneration operations for large naval vessels.These intervals may later be changed depending upon the age of the vessel, the condition of the hull and under-water fittings during a survey etc. When the water is pumped out of the chambers, the dry dock rises and the ship is lifted out of the water on the rising deck, allowing work to proceed on the ship's hull.