The U.S. Navy’s new floating base for amphibious operations, the Mobile Landing Platform (MLP), operates as a transfer point between large supply ships and small landing crafts.
Source: General Dynamics
The MLP designed by General Dynamics NASSCO is a new class of auxiliary ship for the Navy. Once delivered to the fleet, these ships will join the three Maritime Prepositioning Force squadrons that are strategically located around the world to enable rapid response in a crisis. These vessels will change the way the Maritime Prepositioning Force operates. MLPs will provide a “pier at sea” that will become the core of the Navy and Marine Corps seabasing concept. This capability will allow prepositioning ships like LMSR’s and T-AKE’s to offload equipment and supplies to the MLP for transshipment to shore by LCACs or other vessels. MLP ships will be 233 meters (765 feet) in length and 50 meters (164 feet) in beam, with a design draft of 12 meters (29 feet). The deadweight tonnage is in excess of 60,000 metric tons.
MLP Program Overview
Delivers Joint Warfighter Equipment- Each MLP provides
• 3 LCAC berths, skin-to-skin ramp and fenders
• 25,000 sq. ft. raised vehicle deck
Sea Based Surface Interface Hub-Enables personnel and equipment transfer from MPF(F) LMSR and JHSV to shore via LCACs in Sea State 3 conditions.
Commercially Based- Designed/constructed to commercial ship standards. Navy standards and certifications applied to mission-related ship functions. Operated by a 34-person Military Sealift Command crew.
Core Capability Set- Government designed. Constructed under separate contract.
The MLP design is based on the NASSCO-built Alaska Class tanker, which reduces production and technical risks.
Source: NASSCO/General Dynamics Corporation
• Length Overall: 287.25M
• Beam: 50.00M
• Depth: 28.00M
• Design Draft: 18.75M
• Speed at 85% MCR: 15.3 kts.
• Cargo Capacity (98%): 1,300,000 bbls
• Design Deadweight: 185,000MT
• Design Displacement: 220,966MT
• Lightship Weight: approx. 35,950MT
• Twin-screw diesel-electric with total propulsive power of 20.0MW
• Main engines: 4 (each) MAN B&W 6L48/60, 6.3MW, medium speed diesels giving a total installed power of 25.2 MW at 512 rpm
• The diesel engines are designed to operate continuously on either Marine Diesel Oil, ISO 8217 Grade DMC, or Heavy Fuel Oil, ISO 8217 Grade RMH55 (700 cSt @ 50C)
• The electric propulsion plant is an Alstom 6.6 kV system; each motor is synchronous, variable speed, reversible, brushless, double-wound and rated at 10.0MW at 85 rpm
• Synchroconverters to facilitate starting and speed control of main propulsion motors
• Navigation and Communication
Integrated Navigation Bridge System (NIBS):
• Voyage Event Recorder System
• GMDSS Radio System
• 2 dual-interswitched, state-of-the-art radar systems, one 10 cm and one 3 cm, including parallel index lines and EBL
• Two differential GPS navigators
• Power Management System for automatic control of electrical power generation and distribution
Integrated alarm, control, and monitoring system for control and supervision of machinery, electrical, cargo, and ballast systems. httpv://www.youtube.com/watch?v=GEkwplVgGKQ
MacGregor Group designed, built, and tested the Test Article Vehicle Transfer System (TAVTS) as part of the US Navy’s ‘Sea Base’ plan for supporting Army and Marine Corps land forces.
Source: MacGregor News Spring 2010 issue 160
The TAVTS will allow large vehicles [including battle tanks] to pass from a Large Medium-Speed Roll-on/Roll-off (LMSR) ship to a Mobile Landing Platform (MLP) ship. The ramp is power-operated for deployment and retrieval and is controllable by one person. In case of failure, the system is able to safely continue to support vertical and horizontal design loads and allow emergency ship separation with a vehicle – up to a weight of 72,575kg (160,000 lb) – anywhere along the length of the ramp.
Vehicle Transfer System (TAVTS) Highlights:
• The TAVTS is designed to allow emergency ship separation while carrying a 72.5-tonne vehicle anywhere on the 30m-long ramp.
• Successfully transferred personnel and vehicles in Sea State 3 [wave heights 0.5 to1.25] and Sea State 4 [wave heights 1.25 to 2.5] trials.
• Offers large scale logistics movements from sea to shore without dependency on foreign ports.
• Vehicles transferred during tests included high-mobility multi-purpose wheeled vehicles (HMMWVs), HMMWVs with trailers, medium tactical vehicle replacements, logistics vehicle system wreckers, amphibious assault vehicles, M88 tank recovery vehicles, and M1A1 main battle tanks.
Recent News: General Dynamics NASSCO Marks Keel Laying of First Mobile Landing Platform Ship – January 19, 2012