USS Makin Island (LHD-8), a , is the second ship of the United States Navy to be named for Makin Island, target of the Marine Raiders' Makin Island raid early on in the United States' involvement in World War II.
Makin Islands task is to embark, deploy, and land elements of a Marine Corps landing force in an amphibious assault by helicopters, landing craft, and amphibious vehicles. The secondary or convertible mission for Makin Island is sea control and power projection.
Design and construction
Makin Island is the eighth ship of the Wasp class, but features noteworthy technological advances. Changes from the previous LHD design include gas turbine main propulsion engines, all-electric auxiliaries, an advanced machinery control system, water-mist fire-protection systems, and the Navy's most advanced command and control and combat systems equipment. The new propulsion system allows the engines to be directly controlled from the throttles on the bridge, replacing the traditional engine order telegraphs on the earlier Wasp-class LHDs.
Makin Island was laid down on 14 February 2004 at Ingalls Shipbuilding, Pascagoula, Mississippi. The vessel has a light displacement of and a full-load displacement of with a dead weight is . She has an overall length of and a waterline length of . The extreme beam is with the beam at the waterline being and the draft is . Her maximum speed is .
The ship's armament consists of two RIM-116 Rolling Airframe Missile launchers, two RIM-7 Sea Sparrow surface-to-air missile launchers, three Mk 38 25-mm close-in guns, two Mk 15 Phalanx CIWS, four M2 Browning .50 caliber machine guns, and a ceremonial gun.
Makin Island is the eighth Wasp-class amphibious assault ships to be ordered for the U.S. Navy, but differs from her older sister ships in her propulsion system. The previous Wasp-class vessels used steam boilers and steam turbines to drive the propellers, while Makin Island is the first U.S. Navy vessel to use a hybrid propulsion system consisting of a combined diesel electric and gas turbine propulsion system.
Makin Island has two General Electric LM 2500+ gas turbines each connected to a separate 20:1 ratio main reduction gear, which then drive two diameter Rolls-Royce controllable pitch propellers. Gas turbines have a high power-to-weight ratio compared to steam or diesel power, but are only efficient near their maximum power output. In Makin Island, the gas turbines are used to power the ship above 12 knots. Below 12 knots, ship propulsion is provided by two AC electric motors connected to a second input shaft on the main reduction gears. When powered by the electric motors, the gas turbines are decoupled from the main reduction gear and braked to prevent spinning. When the gas turbines are engaged, the electric motors are similarly decoupled from the drive system. The propeller shafts can be driven at lower speeds by slowing down the electric motors. Variable drive speed is achieved with an Alstom variable frequency drive system. Power for the electric motors comes from the ship's service electrical system, which is provided by six 4000 kW generators powered by Fairbanks Morse diesel engines.
In conventional Navy ships, the steam boiler drives both the propellers and ship service steam turbine generators to provide electric power for the vessel. The boilers also provide steam to heat the ship in colder climates. Since Makin Island does not have steam boilers, she uses the diesel electric generators for all shipboard power services. Specifically, instead of steam heating, she uses electric heating for laundry and hot water supply as well as for heating interior compartments in cold climates.
The gas turbine propulsion plant, with all electric auxiliaries, is a program first for large-deck amphibious assault ships and provides significant savings in manpower and maintenance costs associated with traditional steam-powered amphibious ships. The ship carries four reverse-osmosis water-purification systems, each capable of processing of fresh water per day.
The same propulsion systems experimented with in Makin Island will also be used on the s.
She was christened on 19 August 2006, sponsored by Silke Hagee, wife of General Michael Hagee, Commandant of the Marine Corps, and launched on 15 September 2006. In the aftermath of Hurricane Katrina, U.S. Navy officials announced that several ships under construction at Ingalls Shipbuilding had been damaged by the storm, including Makin Island and two s. The ship's completion was delayed due to rewiring during 2008 to repair incorrect wiring installation.