Ship Class Used On	Submarines
Date Of Design	1967 for original proposal
Date In Service (see text)	Mod 0: 1980 Mod 1: 1979 Mod 2: 1986
Weight	3,420 lbs. (1,551 kg)
Overall Length	254.5 in (6.464 m)
Explosive Charge	750 lbs. (340 kg) Torpex
Range / Speed	23,000 yards (21,000 m) / 35 knots about 30,000 yards (27,400 m) / 24 knots
Power	Twin silver-zinc batteries

Mod 0 was an ASW torpedo. When this entered service trials in 1973, the reliability was very poor, about 40% on average functioning as intended. This torpedo depends heavily on data provided by the firing submarine, but the torpedo tended to dip and break the guidance wires during launch. Mod 0 failed provisional fleet acceptance trials in 1979 but was issued to the fleet starting in 1980. Mod 1 had an anti-ship seeker, but experienced problems with the shipboard tactical-data system and with actual torpedo control. During this time, the Royal Navy Torpedo Factory (RNTF) was closed and production passed to Plessey. The redesigned Mod 1 version passed trials in 1978 and was issued to the fleet the following year.

However, in a test performed in 1982 immediately after the Falklands War, two out of five Mod 1 torpedoes fired at a target hulk failed to function because of bad batteries and none of the others even hit the target. This unreliability was well known in the Fleet, which is why ancient Mark 8 torpedoes were used to sink the Argentine cruiser General Belgrano.

A Consolidation Program (i.e., "get well") undertaken by Marconi during the mid-1980s improved the reliability to 80%, which was considered satisfactory. Torpedoes built to the new standards were designated as Mod 2, and all 600 existing Mark 24 torpedoes were modified to this standard by 1987. In 1990 Cardoen of Chile obtained a license to manufacture Tigerfish for the Brazilian, Chilean and Venezuelan navies.

The Royal Navy has removed all Tigerfish from service as of February 2004.

Ship Class Used On	Submarines
Date Of Design (see text)	1978
Date In Service	1994
Weight	4,077 lbs. (1,850 kg)
Overall Length	about 234 in (5.950 m)
Explosive Charge	661 lbs. (300 kg)
Range / Speed	1981 version: About 23,000 yards (21,000 m) / 60+ knots 1994 version: Range unknown / 80+ knots
Power	HAP-Otto Fuel (pump-jet propulsor, turbine engine) (HAP stands for hydrogen ammonium perchlorate)

Spearfish was the result of feasibility studies conducted in 1977-1979 which led up to Naval Staff Target (later requirement) 7525. Marconi produced a design to this requirement in 1978-1979 based upon co-producing it with the Stingray torpedo and sharing components between the two. This design never reached the pre-production stage as the requirements were constantly changed by MOD and production was further delayed by the decision to reopen the bidding process in 1989 to include Dowty and British Aerospace proposals. Marconi produced about 100 pre-production torpedoes during the late 1980s but it is not known how much these resembled the final design. In mid-1990, MOD suspended orders in hopes that Spearfish would be adopted as a standard European weapon. This torpedo is wire-guided with with both active and passive acoustic homing seekers. Speed is reportedly significantly reduced at great depths because the pump-jet design cannot handle the high backpressures.

These torpedoes proved unreliable in early service use. A series of Consolidation Programs (i.e., "get well") by Marconi between 1990 and 1994 improved the reliability to a "satisfactory level," probably greater than 80%. These programs lead to many detailed changes being implemented to the torpedo's design and included the introduction of static testing and pre-conditioning during their manufacture along with environmental screening of the completed torpedoes to screen for faulty components.

The guidewires for this torpedo are were originally made from a copper-cadmium alloy. As cadmium is environmentally unfriendly, a program to change over to a fiber optic system was started in 2004.

Ship Class Used On	Aircraft / ASW Helicopters
Date Of Design	Mod 0: 1977 Mod 1: 2002
Date In Service	Officially in 1986, but the HMS Antelope reportedly had four onboard when she was sunk during the Falklands War in 1982. Mod 1 was scheduled for operational service in 2006.
Weight	588.5 lbs. (267 kg)
Overall Length	102.4 in (2.600 m)
Explosive Charge	99 lbs. (45 kg) Shaped Charge Torpex (it was been proposed that this be replaced by PBX-104, a plastic explosive, but this plan has apparently been abandoned)
Range / Speed	8,750 yards (8,000 m) / 45 knots
Power	Magnesium/silver-chloride seawater battery (Pump-jet)

Mod 0 is a homing torpedo using active acoustic, dual-frequency FM pulses and preformed beams. Purchased in preference to the USN Mark 50 lightweight torpedo. In 1981 the design team for the Stingray torpedo claimed depth performance equal to a Soviet Alfa-class submarine, which would equate to about 800 m.

BAE Systems was awarded a £441m contract in 2003 to supply the Royal Navy and Royal Air Force with the next generation of lightweight torpedo, the Mod 1. Sting Ray Mod 1 is intended to have an enhanced capability against small conventional submarines and an improved shallow-water performance. Mod 1 will use a new digital homing system to enhance the weapon's acoustic and tactical performance and also includes a shaped-charge Insensitive Munitions warhead. The torpedo is to incorporate new technologies in order to greatly reduce the maintenance requirements and allow easy upgrades to its software.