|
The Norwegian Navy has an operational requirement for operations
over a long coastal line, in the Economic Exclusion Zone (EEZ) and
in support of international operations. The Navy requires to
operate a large number of vessels, equipped with relatively large
weapons load. One of the systems that will take the challenge is
the new 270 tons Skjold Surface Effect Ship (SES). In November
2003 the Norwegian Navy ordered five Skjold class boats to join
the first boat, in service since 1999, which is currently
undergoing reconstruction.
The Skjold class boat
utilizes an an advanced GRP (glass reinforced composites)
construction, designed as an air cushion-integrated catamaran design, that offers
excellent cruising speed, high transit speed, and high agility in
open sea and shallow-water operability.
The deck area, parts of the bulkheads, superstructure and hull
areas are constructed of hard composite foam (Polymethacrylimide
or
PMI), which
serves as structural sandwich for demanding structures offering
superior strength-to-weight ratio and high resistance to
temperature. The weight savings achieved by utilizing the foam is
approximately 2000 kg.
The stealth design
uses extensive Radar Absorbing Materials (RAM) construction in the
load carrying structures. Specific attention has also been made to
develop special doors and hatches for reduced radar cross section.
Other signature reduction techniques are applied to reduce thermal
and magnetic signatures. The missiles are integrated inside the
GRP hull, to further reduce signature and streamline the external
envelope.
The first Skjold prototype built in 1997 is
powered by two main engines - Rolls Royce Allison 571 KF 6000kW
(2x8160 Hp) gas turbines driving two kaMeWa 80SII waterjets. The cushion
is pressurized by lift fans, powered by two MTU 12V TE92 735 kW
engines. The combined propulsion offers the boat to accelerate and
maintain top speed above 47 knots, at sea state 3, and 55 knots in
calm water. The boat can also travel at 8 knots by diesel power. In January 2004 Pratt &
Whitney Marine Systems, Inc., was contracted by the
Norwegian shipyard Umoe Mandal, to supply gas turbine propulsion
for COGAG configuration (combined gas turbine and gas turbine)
systems for the six Skjold boats (five new, one reconstructed). Each gas turbine propulsion system will feature
two ST18M marine gas turbines and two ST40M marine gas turbines.
The ST18M and ST40M are free turbine turboshaft engines derived
from Pratt & Whitney Canada's PW100 and PW150A aviation turboprop
powerplants respectively.
Skjold will be equipped with Kongsberg surface missiles, currently
under development, and an Oto Melara 76mm super rapid gun mount or
an 57 mm or 76 mm gun
will be installed on the fore deck.
and integrates eight Mistral anti-aircraft missiles, for
self defense. The first Skjold class fast patrol
boat prototype became operational in 1999, as part of the
Norwegian Navy modernization of its Missile and Torpedo boat
units. Five more boats was are on order.
The Skjold design
provides a basis for the proposed US Navy future Littoral Combat
Ship (LCS), proposed by the
Raytheon-led Team LCS.
Skjold SES
prototype shown during sea trials and
voyage to the USA.
Specifications:
-
Length 47 m
-
Beam 13.5 m
-
Draft 0.9m on cushion, 2.2m off cushion
-
Displacement 270 tons fully loaded
-
Speed at SS3 47 knots
-
Range 800 nautical miles
-
Crew 15 - 18
-
CODOG Propulsion:
2x6,000 kW gas turbines and 2x350 kW diesel
-
Armament: 8xSSM Missiles
-
Air Defense: SAM
-
Guns: 57 / 76mm automatic gun
-
Command and control: SENIT 2000 system
|
