The United Kingdom Surface Ship Torpedo Defence (SSTD) system entered into service with the

Royal Navy The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against F ...

in 2004. The system is produced by

Ultra Electronics Ultra Electronics Holdings is a British defence and security company. It was listed on the London Stock Exchange and was a constituent of the FTSE 250 Index until it was acquired by Cobham, which is itself owned by Advent International. Histo ...

SSTD Datasheet at the Ultra Electronics website
and is known as S2170 or Sonar 270 by the

and as Sea Sentor in the export market. The system consists of * an acoustic passive towed array * a towed acoustic countermeasure (flexible) * a single-drum winch * a processing cabinet * 2 display consoles * 2 expendable acoustic device launchers (1 port, 1 starboard) * 16 expendable acoustic devices (8 in each launcher) The system is a footprint compatible replacement for the

AN/SLQ-25 Nixie The AN/SLQ-25 Nixie and its variants are towed torpedo decoys used on US and allied warships. It consists of a towed decoy device (TB-14A) and a shipboard signal generator. The decoy emits signals to draw a torpedo away from its intended targe ...

system previously installed on RN warships.UK MOD project status
The passive acoustic towed array is specifically designed to detect torpedoes (unlike traditional ASW sonars) and has additional in-built non-acoustic as well as acoustic intercept sensors. Through advanced AI processing it is able to generically identify torpedoes as well as classify specific weapon types and modes and undertake threat evaluation and posturing analysis. The system provides tactical advice dependent upon the specific threat weapon, mode and posture to maximise vessel survivability, which typically involves vessel manoeuvres and also includes the deployment of countermeasures. The countermeasures - both towed and expendable variants - lure the threat away from the vessel in a soft-kill manner. Ultra Electronics also produces a hard-kill variant known as the TRAPR DCL system currently under development for the

US Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of ...

References

{{reflist Close-in weapon systems Military equipment of the United Kingdom Naval warfare Weapons countermeasures