In service with the US Navy since 1995, Harpers Ferry class is the next evolution of the Whidbey Island class dock landing ship.
In service with the US Navy since 1995, Harpers Ferry class is the next evolution of the Whidbey Island class dock landing ship. This design sacrifices landing craft capacity for more cargo space, making it closer to an amphibious transport dock type, but was not designated as such. Externally, the two classes can be distinguished by the positions of weapons: The Harpers Ferry class has the Phalanx CIWS mounted forward, and the RAM launcher on top of the bridge, while the Whidbey Island has the opposite arrangement.
A total of four ships were built between 1991 and 1998: Harpers Ferry LSD-49, Carter Hall LSD-50, Oak Hill LSD-51, and Pearl Harbor LSD-52. These are dock landing ships which support amphibious operations including the landing of forces onto hostile shores.
While the Whidbey Island Class ships were built to transport and launch air-cushioned landing craft (LCAC), and also provide landing facilities for helicopters. The Harpers Ferry Class provides an increased cargo capacity and reduces the number of air cushioned landing craft carried from four to two. As well as 340 crew members, the ships have capacity for 500 troops.
Harpers Ferry-class has a displacement of about 15,939 tons, a length of 185.8 m, a beam of 26 m, and a draft of 5.94 m. The Propulsion system is four Colt Pielstick, 16-cylinder diesels twin turbo, two shafts, 33,000 shp, for a top speed of up to 24.5 knots.
As of 2009, all ships of the class are scheduled to undergo a midlife upgrade to ensure they remain in service through 2038. Major elements of the upgrade package include diesel engine improvements, fuel and maintenance savings systems, engineering control systems, increased air conditioning capacity, and replacement of air compressors. The ships also replaced steam systems with all-electric functionality that will decrease maintenance.
The ship has a landing platform for two Sikorsky Sea Stallion helicopters. The Sea Stallions helicopters, designation CH-53D, each have the capacity to carry up to 38 Marines and are equipped to carry out assault, support and transport operations.
The ship’s surface-to-air missile is the fire-and-forget Raytheon rolling airframe missile, designation RIM-116A, which defends the ship against anti-ship missiles. The range of the missile is from about 1km to 9.5km. The ship is equipped with two 20mm six-barrel Raytheon Phalanx mk15 close-in weapon systems. The Phalanx fires 3,000 rounds a minute to a range of 1.5km. The ship also has two 25mm mk38 and eight 12.7mm machine guns.