NAVYPEDIA

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Pearl Harbor 2003

Ships

No	Name	Yard No	Builder	Laid down	Launched	Comm	Fate
LSD49	Harpers Ferry	2359	Northrop Grumman Avondale, New Orleans	15.4.1991	16.1.1993	7.1.1995	in service (2019)
LSD50	Carter Hall	2369	Northrop Grumman Avondale, New Orleans	11.11.1991	2.10.1993	30.9.1995	in service (2019)
LSD51	Oak Hill	2371	Northrop Grumman Avondale, New Orleans	21.9.1992	11.6.1994	8.6.1996	in service (2019)
LSD52	Pearl Harbor	2379	Northrop Grumman Avondale, New Orleans	27.1.1995	24.2.1996	27.4.1998	in service (2019)

Technical data

Displacement standard, t	11251 - 11604 light
Displacement full, t	16088 - 16601
Length, m	176.8 wl 185.8 oa
Breadth, m	25.6
Draught, m	6.04 hull
No of shafts	2
Machinery	4 Colt-Pielstick 16PC2.5 V400 diesels
Power, h. p.	41600
Max speed, kts	22
Fuel, t	diesel oil 2000
Endurance, nm(kts)	8000(18)
Armament	LSD49-51: 2 x 1 - 25/75 Mk 38 Bushmaster, 2 x 6 - 20/76 Mk 15 Phalanx, 8 x 1 - 12.7/90, helicopter deck LSD52: 2 x 21 RAM SAM (42 RIM-116), 2 x 1 - 25/75 Mk 38 Bushmaster, 2 x 6 - 20/76 Mk 15 Phalanx, 8 x 1 - 12.7/90, helicopter deck
Military load	2 LCAC or 1 LCU or 4 LCM(8), 2 LCPL, 402 troops, vehicles
Electronic equipment	SPS-67(v)1, SPS-49(v)5, SPS-64(v)9, 2x Mk 90 radars, SLQ-32(v)2 ECM suite, 6x Mk 36 SRBOC decoy RL, SLQ-25 Nixie torpedo decoy
Complement	334

Standard scale images

Graphics

Project history

A new LSD41 class was proposed to replace the eight Thomastons, but the Carter Administration deferred construction until Congress voted $41m in long-lead items in FY80; the Administration then announced the construction of six ships in alternate years, beginning in FY81. LSD41 has an enlarged well deck, 134.1x15.2m, adapted to carry four air cushion landing craft (LCAC) or twenty-one conventional LCM (6) landing craft; by way of comparison, the LHD will carry only three LCAC. Docking well can be flooded to 1.8m fwd/3.0m aft, when ship takes 12860t of water ballast. Ships also have 64.6x25.3m flight deck for up to CH-53E-size helicopters but with no hangars. 90t of aviation fuel are carried. There is 1214m² of vehicle parking space and 149m³ hold for palletized cargo fwd of the docking well.

LSD41 was conceived as a near-repeat of Anchorage (LSD36) adapted to LCACs rather than LCMs. That required not only enlargement of the well deck, but also raising the helicopter deck to provide all-round ventilation for LCAC gas turbines. LSD 44-48 are further modified to incorporate collective protection against chemical or biological weapons.

LSD49 and beyond are a modified Whidbey Island design, officially called the LSD41 Cargo Variant. They were originally requested under the FY88 budget, then withdrawn due to late design changes, and then approved by Congress. The idea originated in an analysis of Marine amphibious assault requirements, which showed that more cargo space was needed, but not in the ratio to LCAC 'spots' implicit in the LSD41 design. LSD49 was conceived as a simple substitution of cargo volume for well deck volume (leaving space for two LCAC or ten LCM). LSD49 has 1208m² of vehicle parking and 1133m³ of cargo volume. LCPLs on the deck are handled by one 30t crane.

Plans called for a total of ten, beginning with LSD49 in FY88, LSD50 in FY90, then one per year after that. The 1992 budget stopped production at LSD51, but Congress included LSD52 in the FY92 programme.

Modernizations

1997-1999, Harpers Ferry, Carter Hall, Oak Hill: + 2 x 21 RAM SAM (42 RIM-116)

late 2010s, some: - SPS-64(v)9 radar; + SPS-73 radar, SLQ-49 decoy RL

Naval service

No significant events.