Related content
Descubierta class corvettes
European aircraft carrier cruisers
Soviet/Russian frigates
Model 1968 100-millimeter cannon
Crotale Naval missile launcher
Dagaie ECM launcher
|
The light multirole frigates of the La Fayette class are originally operated by the French Navy, but derivatives of the type are in
service in the Royal Saudi Navy, the Singaporean Navy and the Taiwanese Navy. France ordered five ships of this class in 1988, which
were commissioned between 1996 and 2002 (La Fayette, Surcouf, Courbet, Aconit and Guépratte).
These were the first warships in the world built with a radical stealth design. A reduced radar signature was achieved by means of a
very clean superstructure in comparison to conventional designs, inclined surfaces and radar-absorbent material, a composite of wood
and fiberglass which is light but also as hard as steel and resistant to fire. Most modern warships built around the world since the
introduction of this class have followed the same principles of stealth design.
When the first unit of the La Fayette class was commissioned in March 1996 her stealth design seemed revolutionary. The absence of external
elements of any kind was such that it seemed like the ship was still not finished. Any element which were susceptible to produce radar
echoes had been carefully protected behind bulkheads or curtains, leaving uncovered only which is absolutely imprescindible. The shape of
the hull and superstructures allowed a reduction of radar signature of about 60 percent. A smaller radar signature would allow these ships
to be perceived by radars as a much smaller ships, while helping as well to evade enemy missiles and fire control systems. Inclined and
clean surfaces made of particular synthetic materials are the key for achieving this purpose.
Another less obvious stealth techniques were included as well in the design: low-powered engines to reduce thermal and acoustic
signatures, heat dissipation systems on engines and exhausts to reduce thermal signature (diffusing panels and infrared filters),
elastic supports for the engines and rubber coating in the propellers to reduce acoustic signature or a demagnetization belt to reduce
magnetic signature. A more special method is the active acoustic camouflage system, which generate small bubbles underneath the hull to
confuse sonars.
Finally, the conventional dotation of electronic jammers and decoy launchers are the active response against threats when the passive
stealth techniques have failed. The La Fayette class is equipped with two Dagaie ECM (Electronic Counter Measures) launchers, which
have ten replaceable containers, each loaded with either chaff grenades or infrared flares, which provide protection against radar-homing,
heat-seeking and dual-capable missiles. This system is activated by radar, ESM (Electronic Support Measures) or optical systems, with
a reaction time of less than four seconds, and the optimal firing direction is computed from a combination of threat bearing, wind
speed and direction and the own ship's heading and speed.
These ships, built with high-resistance steels, have a double hull going from the waterline to the deck to better absorb the impact of
a missile. Both hulls are separated by a corridor running from end to end on the body formed by the superstructure, constituting some
kind of "gallery of services", most of them redundant and hence not affecting the operativity of the ship if destroyed by an impact from
a missile.
Vital spaces were protected with 10-millimeter thick steel armor and the main deck has a long and wide corridor which provides direct
access to every room located on it. The structures of the funnels and other elements in the highest parts of the ship were built with a
laminate of balsa wood and glass-reinforced plastics, which has fireproof properties and a very reduced weight. This material was used
also for the sides of the cannon mounting.
The frigates of the La Fayette class have an overall length of 125 meters, a beam of 15.4 meters and a draught of 4.1 meters. Their standard
displacement is 3200 tonnes, reaching 3600 tonnes at full load. The propulsion plant comprises four Diesel engines SEMT Pielstick which develop
5250 horsepower each and actuate on two shafts, allowing a maximum speed of 25 knots. Operational range is around 7000 nautical miles
(11300 kilometers) at 15 knots. The complement is around 140 men and the resources onboard include 60 tonnes of potable water and food
for 50 days. There is also space to accommodate a 10-tonne helicopter.
Curiously so carefully constructed ships were fitted with a rather poor armament, for they only have one 100-millimeter 55-caliber cannon,
two 20-millimeter cannons, two 12.7-millimeter machine guns, two quadruple launchers for the antiship missile Exocet MM40 Block II and
one octuple launcher for the point-defense missile system Crotale Naval.
Provisions were made for the installation of a vertical launching system for the antiaircraft missile Aster 15, probably associated to the
multifunction radar Arabel and the medium-range air defense system known by the French acronym SAAM, but as 2016 this upgrade has not
been installed due to economic reasons. Also antisubmarine armament is inexistent, unless we consider as such the helicopter onboard,
one AS 565 MA Panther or NH 90 Super Frelon.
|
