The old LSD USS Ponce, which will retire March 30 from her current service role, has been identified for conversion into an Interim Afloat Forward Staging Base capable of spending long periods of time in the middle east, “supporting minesweeping operations and acting as base for CH53 heavy helicopters, including those in the mine-countermeasures role”. Crew will be mixed, with regular officers and sailors from the US Navy joined by civilian mariners employed by Military Sealift Command (MSC) giving her an hybrid crew similar to those used on the Navy’s two submarine tenders and the command ship Mount Whitney.
The list of requirements shows more ambitions that just that stated mission of acting as a minesweeper tender, though: the interim AFSB will be a mothership for special forces operations and sea control, as well as a base for RIVERINE boat squadrons operating in the littoral environment. The Minimum Requirements in fact include:
- Berthing and messing for 370
- Supplies and provisions for at least 14 days, ship must operate 24/7
- Extensive communications fit, with 4 video teleconferencing (VTC) capable planning/conference spaces capable of accommodating 25 personnel each, plus an Operations Center for 20.
- Extensive small-boat support facilities, with the ability of simultaneously mooring and refueling:
· 2 Riverine Command Boats (CB90H modified for american use)
· 4 Small Unit Riverine Crafts (heavily armed boats similar in concept to the Royal Marines's Offshore Raiding Craft)
· 4 MK5 Zodiacs
· 2 7 meter RHIBs
- 2 cranes, one per 10.000 and one per 15.000 lbs capable, with 40 feet reach outwards, the second capable to lower loads all the way down to water level, the first reaching the Aviation Maintenance Area
- Flight deck capable to accommodate simultaneously 4 CH53 helicopters
- Additional Open Deck space for staging kit, 150 feet x 150 feet, contiguous to Flight Deck
- Additional Aviation Maintenance area of 100 x 150 feet, must be at reach of the first crane
- 10.000 gallons of JP5 fuel and two fuel stations on flight deck plus one in the open staging area
The US Navy is now moving real fast towards sea bases.
In the near future, past this interim solution, one/two Afloat Forward Staging Bases will be required from 2014, and it appears that, for commonality, the US Navy will build them starting from the Mobile Landing Platform already on order, in itself an evolution of civilian Float On, Float Off (FLO/FLO) heavy load vessels.
Three MLPs have been funded for construction at the General Dynamics National Steel and Shipbuilding (NASSCO) shipyard in San Diego. The ships are large, 765-foot-long vessels intended to serve as a transfer station or floating pier at sea, improving the U.S. military’s ability to deliver equipment and cargo from ship to shore when friendly bases are denied, or simply don’t exist. That’s very useful in disaster situations, and equally useful for supporting US Marines once they’re ashore.
Joint High Speed Vessels (ferries), Prepositioned ships (massive Ro-Ros and other supporting vessels derived from civilian designs) and other units not suited for amphibious assaults, with no landing crafts and with a big draft which would normally need a port in order to unload the massive numbers of vehicles and stores they carry, will be able to transfer their payload at sea onto the Mobile Landing Platform (so long as they have side ramps and Sea State is no higher than 3), which will serve as a staging point thanks to a 80.000 square feet mission deck and will have 3 lanes for LCAC landing crafts that will be able to embark the kit and vehicles and bring it all ashore, going back and forth and needing no ports. Transfer of vehicles at sea is eased by the fact that the MLP’s ability to submerge decreases the relative motion problem for offloading in waves, and its modern dynamic positioning system (from Converteam, heavily involved in the propulsion systems of Type 45 destroyers and CVF, in the UK) should improve standoff distance significantly.
An interface to work with older, slower but larger Landing Utility Crafts is also sought, along with proper connections for lighterage and floating piers.
|Concept art of the Mobile Landing Platform: the berths for the 3 LCAC and the massive Mission Deck are evident.|
The massive Mission Deck is available for incorporating, in future, Berthing modules and Troop Accomodations, Medical facilities, Command and Control, Mission Planning, Connected Replenishment, one container-hangling crane, aviation operating spots and the already tested Test Article Vehicle Transfer System which would enable at sea transfer of vehicles including M1 Abrams tanks in Sea State 4.
TAVTS and helicopter sports and aviation facilities were once part of the original, much more ambitious requirement for the MLP, but were deleted to ensure the design would stay cheap: a Mobile Landing Platform in its current form costs 425.9 million dollars as for FY2012 funding request. They will have a 15 knots speed and a 9500 naval miles range, with a lenght of 255 meters and a beam of 50.
The three MLPs on order are to be named: USNS Montford Point, USNS John Glenn and USNS Lewis B. Puller. They will be operated by the US Military Sealift Command, not by the Navy itself.
For the AFSB role, a fourth MLP will be built, modified with several decks atop the Mission Deck, including a hangar, topped by a large flight deck able to operate the heavy H-53s in the airborne mine countermeasures role, MV-22 troops transports and other helicopters.
The AFSB will also be able to carry Marines, support patrol and special operations craft, and fuel and arm other helicopters.
The first AFSB is expected to be requested in 2014, but the third MLP on order might be turned into an AFSB as well.
There are and will be alternative approaches available in future, though: one of the most interesting is this Maersk proposal for conversion of their massive S-class container ships (357 meters long and 42.8 wide, with 25 knots speed). They offer 40-tons cranes, Ro-Ro space for 144 Humvee-sized vehicles or loads of other vehicles, the TATVS interface, hangar and flight deck for 15 MV22 Osprey, 200-beds hospital and modular accommodations and spaces for "up to 6000" men, with 30 days endurance without replenishment. Their cost estimate of 400 million is, however, clearly wildly optimistic.
It remains a very fascinating and interesting proposal. See the video below, and the brochure here.
I made my personal proposal as well, for a barge combining MLB and AFSB functions, delivered via commercial FLO/FLO vessel, targeted at the Royal Navy. It can be seen in detail here.
|My own proposal for the Joint Sea Base; Logistics, targeted at the Royal Navy|