What is "tigerfish"

n. Any of several species of fish with stripes on their bodies, otherwise fearsome appearance, or aggressive predatory behavior.

The Mk 24 Tigerfish torpedo was a heavyweight acoustic homing torpedo used by the Royal Navy (RN) for several years. The early Mod0 and Mod1 variants were unreliable and unsuccessful, but were issued to the RN even though they failed Fleet Weapon Acceptance. Reliability was significantly improved in the Mod2 variant as a result of the Consolidation Programme which addressed the complete weapon system i.e. the on-board fire control system (TCSS10 and DCB) and the Mk24 torpedo. The Consolidation Programme was initiated following the torpedo's reliability failures during the Falklands War. It was headed by Marconi Underwater Systems as prime contractor with Ferranti Computer Systems and Gresham Lion as major sub-contractors. The Tigerfish was eventually replaced in Royal Navy service by the more capable Spearfish torpedo.

The Tigerfish was fitted with both active and passive sonar and could be remotely controlled through a thin wire which connected it to the launching submarine. Wire guidance permits a torpedo to be launched on-first-warning, i.e. when a target is first detected at long range. This permits the torpedo the time needed to close the range while target course and speed is being updated by the submarine's superior sensors and transmitted 'down-the-wire'. The torpedo can also be reassigned to another target or recalled. Typically, wire-guided torpedoes initially run at low speed (in order to maximize their range and to minimize their self-generated noise) while they close the range (the approach speed) and speed up during the attack phase (the attack speed).

Tigerfish can refer to fish from various families, and derives from official and colloquial associations of these with the tiger (Panthera tigris). However, the primary species designated by the name "tigerfish" are African and belong to the family Alestidae.