In early 2013, the U.S. Navy received the first (USNS Montford Point) of three T-ESD (Expeditionary Transfer Dock, formerly T-MLP) ships. Montford Point successfully completed its sea trials and entered service in early 2014. The Navy completed another T-ESD in 2013. Instead of building more of this design, the Navy switched to a different (but similar) design: T-ESB. Originally, the Navy sought to use the T-ESD design as floating bases to support commando-type operations ashore. The T-ESDs are 34,500-ton vessels that serve as seagoing piers when no friendly port is handy. Each is 239 meters (785 feet) long and has up to 2,322 square meters (25,000 square feet) of space to store vehicles and aircraft. The second two T-ESDs were to be equipped as an AFSB (Afloat Forward Staging Base), with added command-and-control equipment (electronics and communications gear) and a distinct flight deck area.
The T-ESD looks like a container ship, with the main deck lowered to about dock height. On the side of the T-ESD are mooring fenders (so cargo ships can, literally, tie up like at a dock). The T-ESD also has ramps for loading and unloading cargo from ships or a dock. Cargo would be transferred to landing craft or LCACs (air-cushion high-speed landing craft that can carry 60 tons of cargo). The T-ESD can also partially submerge itself so that its main deck is underwater. Landing craft can then move over the deck, and the T-ESD can bring its deck back out of the water so the landing craft can be loaded. T-ESDs are to carry three LCACs. AFSBs can also carry helicopters and MV-22 tiltrotor aircraft. The Navy plans to increase the fire resistance of part of the deck so AFSBs can also handle the F-35's vertical-takeoff variant.
The T-ESD and T-ESB are built to commercial (not military) ship standards and use civilian crews (as with all USNS ships). They can be equipped with defensive (anti-missile) systems.
Work on these concepts began earlier. In 2012, the American LPD USS Ponce (an amphibious ship with a dock in the rear for small boats) was rapidly modified (in five months) to serve as a support ship (mainly for mine clearing, but also for disaster relief or supporting commando operations). Normally, these LPDs carry a reinforced battalion of Marines, plus six CH-46 helicopters and 39 landing craft (24 of them AAV infantry fighting vehicles). The Ponce is a 17,000-ton ship with a crew of 420, plus space for 900 Marines, vehicles, or cargo. The shipyard conversion converted many berthing spaces into work areas (for headquarters or training). Since the converted ship needs half as many crew members, the crew quarters were remodeled to be roomier and more comfortable. The modified Ponce was equipped to support smaller mine-clearing ships and helicopters, and to serve as a floating base for MH-53 mine-clearing helicopters. It also carried more communications gear and special equipment, such as drones and naval drones (unmanned submarines the size of torpedoes used to find mines). The Navy redesignated it from LPD-15 to AFSB-15.
This wasn't a new concept; in 2006, the Navy sent an Austin-class amphibious ship to the Indian Ocean without the usual complement of Marines. Instead, the ship served as a floating base for drones and SOF (special operations forces). In 2002, the Navy assigned a similar task to a carrier to support SOF operations in Afghanistan. In 2006, the amphibious ship was believed to have also supported SOF operations ashore in Somalia or Iran. The Austins are normally armed with two 25mm autocannons, two 20mm Phalanx for anti-missile work, and eight 12.7mm machine-guns.
James F Dunnigan