The Wasp class is based on the preceding design. The design was modified to allow for the operation of AV-8B Harrier II aircraft and Landing Craft Air Cushion hovercraft, making the Wasp class the first ships specifically designed to operate these. The main physical changes between the two designs are the lower placement of the ship's bridge in the Wasp class, the relocation of the command and control facilities to inside the hull, the removal of the Mk 45 naval guns and their sponsons on the forward edge of the flight deck, and a lengthening of to carry the LCACs. Each Wasp-class ship has a displacement of at full load, is long, has a beam of, and a draft of. For propulsion, most of the ships are fitted with two steam boilers connected to geared turbines, which deliver to the two propeller shafts. This allows the LHDs to reach speeds of, with a range of at. The last ship of the class,, was instead fitted with two General Electric LM2500 geared gas turbines. The ship's company consists of 1,208 personnel.
Amphibious operations
The LHDs can support amphibious landings in two forms: by landing craft, or by helicopter. In the by high well deck, the LHDs can carry three Landing Craft Air Cushion, twelve Landing Craft Mechanised, or 40 Amphibious Assault Vehicles, with another 21 AAVs on the vehicle deck. The flight deck has nine helicopter landing spots, and can operate helicopters and tiltrotors as large as the Sikorsky CH-53E Super Stallion and MV-22B Osprey. The size of the air combat element varies depending on the operation: a standard air combat element consists of six Harriers or six F-35B Lightning IIs and four AH-1W/Z Super Cobra/Viper attack helicopters for attack and support, twelve Ospreys and four Super Stallions for transport, and three or four Bell UH-1Y Venomutility helicopters. For a full assault, the air group can be maxed out at 22 Ospreys, while a Wasp operating in the sea control or 'Harrier carrier' or 'Lightning carrier' configuration carries 20 Harriers or F-35Bs, supported by six Sikorsky SH-60 Seahawk helicopters for anti-submarine warfare. Two aircraft elevators move aircraft between the flight deck and the hangar; in order to transit the Panama Canal, these elevators need to be folded in. mating with a landing craft Each ship is capable of hosting 1,894 personnel of the United States Marine Corps; almost the full strength of a Marine Expeditionary Unit. A Wasp-class vessel can transport up to of cargo, and another is allocated for the MEU's vehicles, which typically consists of five M1 Abrams battle tanks, up to 25 AAVs, eight M198 howitzers, 68 trucks, and up to 12 other support vehicles. A 6 track internal monorail system as well as 6 internal elevators are used to shift cargo from the cargo holds to landing craft in the well deck. Each Wasp-class ship has a hospital with 64 patient beds and six operating rooms. An additional 536 beds can be set up in an "Overflow Casualty Ward" as needed.
Armament and sensors
The armament of the first four Wasp class consists of two Mark 29 octuple launchers for RIM-7 Sea Sparrow missiles, two Mark 49 launchers for RIM-116 Rolling Airframe Missiles, three 20 mm Phalanx CIWSs, four 25 mm Mark 38 chain guns, and four.50 caliber machine guns. The next four ships,,,, and, have a slightly reduced weapons outfit compared to their preceding sister ships, with one Phalanx and one Mark 38 gun removed. Countermeasures fitted to the ships include four to six Mark 36 SRBOC chaff and decoy launchers, an AN/SLQ-25 torpedo decoy, AN/SLQ-49 chaff buoys, a Sea Gnat missile decoy, and an AN/SLQ-32 Electronic Warfare Suite. The sensor suite fitted to each ship comprises an AN/SPS-48 or AN/SPS-52 air-search radar backed up by an AN/SPS-49 air-search radar, an SPS-67surface search radar, an AN/URN-25TACAN system, along with several additional radars for navigation and fire control.
Construction
All Wasp-class ships were built by Ingalls Shipbuilding, at Pascagoula, Mississippi. The first ship of the class,, was commissioned on 29 July 1989. The fifth ship of the class,, was constructed through a process of modular assembly and prefitting out, which meant that the LHD was almost 75 percent complete when she was launched. Bataan was also the first LHD that was purpose built to house female crew members, with dedicated berths for up to 450 female sailors or Marines. Japanese Defense MinisterItsunori Onodera in 2014 suggested that Japan purchase at least one Wasp-class ship to provide robust defensive amphibious capability for Japanese outer islands in the face of Chinese threats.
