LSD-49 Harpers Ferry class
The primary mission of the Harpers Ferry (Cargo Variant) ship is to dock, transport and launch the Navy's Landing Craft, Air Cushion (LCAC) vessels and other amphibious craft and vehicles with crews and Marines into potential trouble spots around the world. The ship also has the capability to act as primary control ship during an Amphibious Assault.
The ships were designed as a minimum modification variant of the LSD 41 Whidbey Island Class with increased cargo capacity, and contains the same lines and propulsion plant as the first eight ships. The major difference is that the well deck has been shortened to accommodate added vehicle stowage and cargo storage areas, reducing the number of LCAC's carried from four to two, with 1 LCU, 4 LCM(8), or 9 LCM(6). It carries one utility boat and 2 LCPL on deck, tended by a single starboard side 30-ton crane. Have greater air-conditioning capacity than the LSD 41 class.
As of October 1994, self-defense configurations for the combined LSD 41/49 class included the SPS-49 air search radar and the SLQ-32 electronic warfare system. Though the control function was being performed manually throughout the class, the Navy completed operational testing of an automated control system (SSDS MK I) in June 1997 aboard the USS Ashland (LSD 48). Engagement relied primarily upon Phalanx Block 0 or 1 and the Mk 36 decoy launching system. As measured by the Navy's performance assessment model, this configuration produced a performance result that was far below the threat requirements for the class.
Since October 1994, the Navy has taken several actions to enhance the LSD 41/49 class's ability to defeat cruise missiles. The Navy enhanced detection capabilities by adding a medium pulse repetition frequency upgrade to the SPS-49 radar and integrating the Phalanx radar with the control system. To improve the control function, the Navy installed SSDS MK I on four LSD 41 and two LSD 49 class ships. In addition, to improve engagement capabilities, the Navy completed installations of the Phalanx Block 1A upgrade on two LSD 49 class ships. In addition, RAM Block 0 was installed on three LSD 49 class ships. With these installations, the Navy more than doubled the class's ability to counter current and future missile threats since requirements were adopted in February 1996. However, additional improvements in capability are needed to meet requirements for near-, mid-, and far-term threats.
Two recent development efforts, RAM Block 1 and NULKA, are planned for future installation in the LSD 41/49 ship class. Once installed, the Navy expects that these improvements will provide these ships with a high capability against the near-term threat, moderate to high capability against the mid-term threat, but a low capability against the far term threat.
All ships of the class are to have received the SSDS Block 1 combat system by 2004, beginning with LSD 49 in 1997. Although the Navy has made some progress in improving surface ship self-defense capabilities, most ships continue to have only limited capabilities against cruise missile threats. A Navy assessment of current surface ship self-defense capabilities conducted in 1998 concluded that only the 12 Whidbey Island and Harpers Ferry class amphibious ships have or will be equipped with defensive systems that can provide measurable improvement against near- and mid-term cruise missile threats. These 12 ships have received, or are scheduled to receive, an improved version of the SPS-49 radar, the Ship Self Defense control system, the Rolling Airframe Missile system, and the Phalanx Block 1A. The Navy estimates that these improvements, when completed, will more than double the assessed capability of these ships to defeat near- and mid-term threats. However, they will provide only low capability against far-term threats.
Dock Landing Ships support amphibious operations including landings via Landing Craft Air Cushion (LCAC), conventional landing craft and helicopters, onto hostile shores. These ships transport and launch amphibious craft and vehicles with their crews and embarked personnel in amphibious assault operations. The ships combat load, transport and launch amphibious craft, or vehicles, together with their crews and embarked personnel, and render limited docking and repair services to small ships and craft.
Wheeled vehicles can be embarked/debarked via three methods: pier crane, ship's crane, or the well deck. The well deck will accommodate one (1) LCU or two (2) LCACs. Vehicles may be onloaded/offloaded via the well deck by either landing craft while the ship is ballast down or by dropping the stern gate and backing up to a quay wall. The ships are equipped with a hydraulically-operated stern gate. This system has a watertight hinged closure located at the stern which swings out and down to permit entry of landing craft and vehicles into the well deck. The port and starboard hydraulic rams raise or lower the gate in approximately (5) minutes and provide positive control of the gate during travel. The stern gate can support the weight of two (2) AAVP7A1 Amphibian Vehicles, an M60A1 or M1A1 Main Battle Tank, or two (2) M923 5 ton trucks simultaneously.
Loaded LCAC's can be launched while underway on their own power. The ship needs to be ballasted at 0 - 6 inches at the sill. Loaded conventional landing craft (such as LCU, LCM-8, or LCM-6) are launched under their own power with the ship ballasted down sufficiently to float the craft. Amphibious vehicles (such as LVT and LARC-V) are launched under their own power with the ship ballasted just below the sill. The practice of carrying AAVP7s and conventional landing craft in the same well should be avoided for safety reasons. It does not provide a dry well for an AAVP7 in trouble to return due to the ballasting for the launch of the landing craft. In addition, if AAVP7s are stowed alongside a LCU in the well deck there is not enough room to fully shore up the LCU, thus creating a safety hazard in heavy weather.
The flight deck is fixed, as on LSD 41 class, has two landing spots, and is served by an 8-ton cargo elevator. Lighting, visual landing aides, and flight deck facilities are provided to allow launching / landing, and VERTREP/hover under minimum conditions of day and night VFR. The two landing spots allow for operation of aircraft as large as the CH-53E.
When the Department of the Navy lift study was completed in May 1983, the authors realized the most critical shortfall not addressed up to that time was in cargo lift capability. Thus the follow-on to the LSD 41 class was born. At first it was to be a new class of ship; however, as the process of design approval continued, the Navy realized that considerable time and money could be saved by modifying the LSD 41 class, for the LSD 49 and beyond. In the forward half of the LSD 41 well deck, in the area allocated for two LCAC, Naval Sea Systems Command designed a covered ramp with cargo space beneath. Other changes were necessary in various parts of the ship to compensate for the added weight, but essentially, the changes amount only to a broad modification of the baseline ship.
The class was called LSD 41 Cargo Variant class (or LSD 41(CV). In 1987, the Navy requested $324.2 million to fund one LSD-41 (Cargo Variant). USS HARPERS FERRY (LSD 49) was built by Avondale Industries in New Orleans, Louisiana. It was commissioned on January 7, 1995, the first of the United States Navy's four new cargo variants of the Whidbey Island Class (LSD 41) of Landing Dock Ships.
To achieve force level objectives, there were to be at least six LSD 41(CV) ships in addition to the mix of LHDs, LSD 41s, and other amphibious ships. Beyond that, the Navy expected to keep building the LSD 41(CV)s to sustain the lift capability as older ships retired. As of 1989 estimates were that 12 LSD 41(CV)s might eventually be delivered. Procurement plans provided for the Navy to request one LSD-41(CV) per year through 2000 in order to continue to meet the amphibious lift requirement. In 1991 Navy requested $245,134,000 for the LSD -41 Cargo Variant, but the appropriations conferees provide no funds for the program. Due to cost growth in the program, in 1992 the House appropriated addition money for the LSD-41 cargo variant program, in the amount of $27,000,000 for 1992, $31,000,000 for 1994, and $30,000,000 for 1995. The Senate appropriated a total of $300,000,000 for the LSD-41 cargo variant ship program, in addition to the House figures for cost growth on the prior years program. Although no funds were requested for the program the following year, $300,000,000 was appropriated at the initiative of the House.
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