Lamprey (torpedo)

AT-01 Lamprey
Type	Anti-torpedo torpedo
Place of origin	Chilokver
Service history
In service	2015–present
Production history
Manufacturer	Hydronamica Inc.
Specifications
Weight	235 kg
Length	2.6 m (8.5 ft)
Diameter	324 mm (12.8 in)
Maximum firing range	1.9 km (1.0 nmi)
Warhead	PBX warhead
Warhead weight	44 kg
Engine	Solid fuel rocket
Propellant	Solid fuel propellant
Speed	50 kt
Guidance system	Active/passive acoustic homing
Launch platform	Surface ship

The AT-01 Lamprey is a dedicated 324 mm anti-torpedo torpedo used by the Grand Chilokveri Navy (GCN). First tested in early 2015 and entering service later that year, the Lamprey was designed to be backwards compatible with existing 324mm lightweight launchers already equipped aboard Chilokveri surface combatants, paralleling the development of standalone hard-kill torpedo defence systems for the GCN's other vessels (see UDW-2 Anti-Torpedo APS). Future development is expected to see the Lamprey integrated aboard submarine platforms as a three-round tube insert as well.

Development

Background

The capabilities, and therefore threat posed by torpedoes rapidly expanded in the early 2000s as a result of improvements in their propulsion, sensors and guidance systems. New electrically propelled torpedoes were stealthier than their combustion fuelled predecessors, and the digitally processed sonar which now equipped them were increasingly resistant to decoys and jammers. Furthermore, wake-homing torpedoes, fully impervious to legacy soft-kill countermeasures, saw increasing proliferation among foreign navies.

In 2004, a Chilokveri Ministry of Defence internal report concluded that "...it can be seen that advances in heavyweight torpedo technology, coupled with a foreseen increase in littoral operations where anti-submarine warfare is traditionally challenged will lead to the reduction of future GCN underwater defensive capability". As a result, the Grand Chilokveri Navy allocated funding for the development of hard-kill defences for its warships beginning in FY2005. By 2015, this program led to the fielding of an underwater active protection system onboard Chilokveri destroyers and frigates with the production of the AT-01 Lamprey anti-torpedo torpedo.

Design

The AT-01 Lamprey's specifications are similar to those of existing lightweight torpedoes so as to permit the use of legacy launchers. The torpedo measures 324 mm in diameter, 2.6 m in length and weighs 235 kg, 44 kg of which is PBX explosive filling. As a dedicated anti-torpedo torpedo, it is optimised solely for the hard-kill and active elimination of incoming torpedo threats with no multi-mission ASW capabilities. Compared to existing soft-kill systems, the Lamprey is reported to increase torpedo defence effectiveness by "3 to 3.5 times".

Warhead

The Lamprey is equipped with a 44 kg PBX warhead, roughly equivalent in explosive power to 70 kg of TNT. The composition is insensitive and compliant with Chilokveri military standards. The warhead is triggered by proximity fusing to ensure target kills even in the case of a near-miss.

Guidance

The Lamprey's digitized homing sonar is capable of operating in passive, active and intercept mode simultaneously, ensuring optimal homing performance regardless of the threat torpedo properties. The active sonar frequency was chosen for optimal detection capability against wake-homing torpedoes and minimal interference with shipboard sensors. The Lamprey's advanced solid state microprocessor guidance system incorporates special modes against wake homing torpedos and salvo attacks.

While the Lamprey's maximum range at 50 knots is 18.5 km, due to the restrictions of its onboard sensors, it is limited to an effective range of 1.9km

Propulsion

After launch, the Lamprey is propelled to a speed of over 50 knots by its solid propellant rocket. The use of a rocket rather than a traditional propeller/propulsor arrangement achieves high speed, rapid acceleration & excellent shallow water capabilities at a lower cost and with minimal self-noise in the torpedo's sonar frequency. Steering is accomplished using a conventional 4 fin rudder system mounted towards the rear of the torpedo. The Lamprey's maneuverability is reported to be significantly superior to other existing torpedo designs.

Thanks to its solid fuel propellant, so long as the Lamprey is stored in a controlled environment its maintenance can be minimised to depot level examinations and maintenance.