SPEARHEAD CLASS JOINT HIGH SPEED VESSELS (JHSV)*

Joint High Speed Vessels (JHSV) are being built by Austal USA under the JHSV programme initiated by the US Navy.

Operated by the Military Sealift Command, the JHSV will support joint or coalition force operations of the army and navy.

The main roles of the JHSVs are transportation of troops, military vehicles, cargo and equipment for a range of global missions.

The vessel will support military logistics and humanitarian relief operations.

Development and construction of the Joint High Speed Vessels

The preliminary design contract for the JHSV programme was awarded in February 2008. In November 2008, the US Navy placed a $185.4m contract for the detail design and construction of a JHSV with options for up to nine additional ships. The initial critical design review (ICDR) was completed by May 2009.

The first three vessels were named as Spearhead (JHSV 1), Vigilant (JHSV 2) and Fortitude (JHSV 3) on 16 July 2009. The construction of Vigilant and Fortitude was authorised by the US Navy in January 2010.

The keel for the first ship in the class, Spearhead (JHSV 1), was laid at Austal's shipyard at Mobile, Alabama in July 2010. It is scheduled to be launched in August 2011 for delivery in December 2011.

Construction of Vigilant (JHSV 2) began in September 2010. In May 2011, the US Army transferred all five of its JHSVs to the navy. The programme initially called for five JHSVs to the army and five to the navy and Marine Corps. The US Navy exercised contract options for the construction of JHSV 6 and 7 in July 2011.

JHSV design features

JHSV features rounded bilge and bulbous bow hull forms made of aluminium. The catamaran vessel is being built to American Bureau of Shipping (ABS) standards. The onboard systems comply with the commercial ABS steel vessel regulations. The ship will not feature combat systems or the ability to support or use LCS mission modules. JHSV is based on the commercial technology, but includes limited military features such as aviation, C4SI and fire-fighting. The vessel will have a length of 103m, a beam of 28.5m and a draft of 3.8m. Displacement of the ship will be 2,362t. The open unobstructed mission deck will have a usable cargo area of more than 1,800m2 with clear height of 4.7m and turning diameter of 26.2m.

JHSV performance and power

JHSV will operate in shallow-draft ports and waterways, interfacing with roll-on / roll-off discharge facilities and on / off-loading. The stern loading ramp can support a M1A2 Abrams main battle tank. The ships can transport 635t of payload to over 1,200nm at an average speed of 35kt. JHSV will be crewed by the civilian mariners provided by the Military Sealift Command. The vessel will complement a crew of approximately 42 people.

Aircraft capabilities of Austal USA's Joint High Speed Vessels

The JHSV will have a Navair level 1 class 2 certified flight deck to support the operations of one helicopter such as a CH-53E Super Stallion. The ship will be equipped with a centreline parking area for one helicopter, a vertical replenishment area and helicopter control station. Kongsberg Maritime was contracted to supply the JHSVs helicopter operations surveillance system (HOSS). Operated from the control room, the HOSS system allows helicopter operations in very low light conditions. The system integrates a MIL-S-901D shock qualified 19" SXGA LCD monitor suitable for night vision device (NVD) operations.

JHSV propulsion

JHSV is powered by four MTU 20V8000 M71L diesel engines driving four Wartsila WLD 1400 SR waterjets via four ZF 60000NR2H reduction gears. Each engine rated at 9.1MW provides a maximum speed of 43kt without payload. The propulsion system delivers superior fuel efficiency to reduce operating costs.

Crew accommodation

The ship will provide accommodation for 41 crew members in two single staterooms, six double staterooms and seven quadruple staterooms. There will be airline style seating for more than 312 embarked forces as well as permanent berths for approximately 104 personnel and temporary berths for 46 troops.

* Noticia publicada per naval-technology.com. Cosiderem que pot ser interessant pels lectors, com a mostra de les transformacions a la US Navy.