US Navy's 694-Foot Submersible Repair Ship
The floating dry dock AFDM can lift and repair destroyers underwater.
1An unconventional naval vessel
The US Navy's Auxiliary Floating Dry Dock Medium (AFDM) features a completely different design from traditional ships. This massive 694-foot structure enables underwater repairs of destroyers and cruisers. Weighing 12,000 tons with 18,000 long tons lifting capacity, the AFDM can easily handle Arleigh Burke-class destroyers.
2How it operates
The AFDM positions itself by submerging beneath ships needing repairs, then pumps out water to rise while securing the vessel above. Its Rennie-type design with continuous wing walls reaches 65 feet high. The 90,800 sq ft working surface accommodates large-scale repair operations for various naval ships.
3Historical origins
Floating dry docks aren't new; the US Navy has used similar systems since 1902. The first model YFD-2 was sunk during the Pearl Harbor attack in 1941 but was repaired and served in WWII. Over 150 floating docks were built during the war, enabling critical overseas repairs.
4Technical specifications
AFDM's pontoon sections and continuous wing walls provide stable lifting for high-tonnage vessels. It's ideally sized for repairing Ticonderoga-class cruisers (9,600 LT) and Freedom-variant Littoral Combat Ships. Having no engines, the dock requires tugboats for positioning.
5Modernization process
Commissioned on July 28, 2026, the new AFDM enhances the Navy's repair infrastructure. It facilitates maintenance for Whidbey Island and Harpers Ferry Dock landing ships. This specialized marine engineering expertise increases fleet operational readiness.
6Wartime critical role
During WWII, floating docks enabled rapid repairs of damaged ships in the Pacific and Atlantic. Models like USS Dewey (YFD-1) and USS ARD-1 significantly contributed to war efforts. This technology became indispensable for naval logistics and fleet sustainability.
7Design evolution
From the 1902 YFD-2 to today's AFDM, floating docks have advanced considerably. Modern versions offer higher lifting capacity, expanded work platforms, and improved stability systems. These revolutionary maintenance assets extend fleet service life and operational capabilities.
8Future significance
Floating dry docks like AFDM increase naval operational flexibility worldwide. They reduce dependency on port infrastructure for urgent repairs. This technology remains vital for forward-deployed fleets and will continue shaping defense strategies for decades to come.
Original article: SlashGear — ABD Donanması'nın 694 Metrelik Sualtı Tamir Gemisi