The U.S. Navy is looking at engineering plans to turn its floating sea bases into platforms for launching and recovering huge underwater drones and aerial drones. Other adaptations would let unloaded F-35B fighter replacements take off vertically in order to “jump” to their new carriers.
The U.S. Navy’s Expeditionary Sea Bases (ESBs) are heavily modified versions of the Alaska-class commercial oil tanker. Their hulls have been cut down to just a few meters above sea level, while a “floating flight deck” had been placed on high steel pillars, far above the open operations deck.
Although it is based on an oil tanker, the ESB does not refuel other ships and has to be refueled at sea like any other warship. Its low and open operations deck is used to launch small vessels from the side, while its large flight deck and hangar can receive and house four large helicopters or Osprey tilt-rotor aircraft.
These floating sea bases feature large cargo cranes and are packed with support equipment and personnel that vary depending on the mission. They are often used as launch platforms for minesweeping helicopters and for Navy SEAL missions. Soon, they might be transformed into something much more high tech.
The company that builds these large ships, General Dynamics NASSCO, has come up with engineering concepts that would add a huge moon pool with a massive rotating pod in the bottom of the ship’s hull. One other option would be to add a rear flight deck to service helicopter drones, while another option would be to add heat-proof plating to the main flight deck to allow F-35 jets to launch themselves vertically. The company is also proposing a large “clamp and crane” concept that could allow the exchange of large cargo pallets and vertical launch system (VLS) cells between ships at sea.
The biggest adaptation would be to make a huge hole in the middle of the ship’s hull to turn it into a moon pool that would give direct access to the ocean underneath. The other huge addition would be a massive rotating mechanism that would fill the moon pool. This mechanism would receive underwater drones as large as the Orca Extra Large Unmanned Underwater Vehicle (XLUUV) and deliver them safely to the water underneath the ship. Without such a mechanism, the moon pool would slosh dangerously during stormy weather and the expensive underwater drones would get damaged.
The XLUUV and other underwater drones are currently in development and would be used to covertly plant smart dormant torpedoes and regular sea mines while also hunting for submarines and performing invaluable surveillance missions.
General Dynamics’ concept would give the U.S. Navy the ability to house a large number of underwater drones inside each ship, while walls of equipment containers would hide these devices from enemy eyes. The Navy would then be able to launch and recover these covert devices from within these walls, without being observed.
By adding an additional flight deck and hangar behind the rear control tower, the ESB would be able to operate multiple helicopter drones, which would be valuable for missions like early warning, radar coverage, information-gathering and submarine-hunting.
By adding heat-proofing to the main flight deck, the U.S. Navy would be able to use these ships to transport F-35B fighters to act as stand-by replacements during a conflict. The F-35B is the short take-off version of the F-35 that can “potentially” take off vertically if it is stripped of all munitions and if it carries only a minimal fuel load. The idea would be to store such fighters on the ESB until they are needed for combat. Then each fighter would jump to its amphibious assault ship to be prepared for combat operations — this would usually occur after an active F-35B is damaged or lost. It is also conceivable that such modified ESBs would be used to receive F-35Bs for servicing or repairs, while giving one of its replacements back to the amphibious assault ship.
Another concept being looked at is to fit ESBs with At-Sea Precision Lift (ASPL) equipment. This would consist of large clamps that would telescope out and attach to another ship just above the water line, in addition to a huge crane that can extend over the deck of the other ship. Such a system would allow the ship to exchange large containers with other ships at sea.
A contractor for General Dynamics NASSCO said such an ASPL system would conceivably be used for “VLS reload,” referring to the reloading of the VLS cells of warships while at sea. VLS cells are the rectangular pods on warships that are used to store and launch missiles. Each warship has a limited number of these cells, and once each cell fires its missile it has to be replaced. It is dangerous to replace these cells while at sea, so the warship has to sail back all the way to a supply port to reload. If an ESB can be fitted with an At-Sea Precision Lift system it would be a huge game-changer, as it would allow U.S. warships to stay in the operational theater while reloading — without the need to waste time and fuel to sail hundreds of miles to the nearest supply port.