The Mk.IX is a British torpedo fitted to a significant number of cruisers. Cruisers other than Japanese cruisers rarely use the torpedo effectively in combat. Occasionally, however, an enemy may be jabbed, or the enemy may be unexpectedly close. In such cases, torpedoes can provide an easy way to defeat the enemy, or a way out of a difficult situation. In this case, the British torpedo is of rather average performance, and a few hits would probably sink the cruiser. Read more about the Mk.IX in the article.
| Pros | Cons |
|---|---|
| Above-average 340 kg TNT explosive mass | Below-average top speeds (67 km/h and 56 km/h) |
| High maximum range (12.35 km) with Torpedo Mode modification |
General info
The Mk.IX torpedo has a diameter of 533 mm, a length of 7.277 m, and weighs 1,693 kg. Without the Torpedo Mode modification installed, it can travel at a maximum speed of 67 km/h for 9.60 km. With it installed, the maximum range is increased to 12.35 km, but the maximum speed is reduced to 56 km/h.
Effective damage
The Mk.IX torpedo carries a 340 kg TNT warhead, which is above average compared to other torpedoes. Destroyers and other smaller vessels can be destroyed by a single hit, but cruisers, especially heavy cruisers, may be able to survive multiple hits, depending on where the hit occurred.
Comparison with analogues
- Mk.VIII (533 mm): An improved Mk.V and predecessor to the Mk.IX, the Mk.VIII has a much higher maximum speed (84 km/h); but it has a much lower maximum range (4.57 km) and has a smaller explosive mass (327 kg TNT equivalence). With the Torpedo Mode modification installed on both, the Mk.VIII has a much higher maximum speed (76 km/h), but it has a much lower maximum range (6.4 km).
- Mark XII: An 18-inch torpedo, the Mark XII has a higher maximum speed (69 km/h); but it has a much lower maximum range (3.2 km) and has a much smaller explosive mass (176 kg TNT equivalence). With the Torpedo Mode modification installed on both, the Mark XII has a much greater maximum speed (74 km/h), but it has a much lower maximum range (1.37 km).
- Type 93 Model 3 (610 mm): The Type 93 Model 3 has a much higher maximum speed (91 km/h), has a much higher maximum range (15 km), and has a much larger explosive mass (998.4 kg TNT equivalence). There is no Torpedo Mode modification available for the Type 93 Model 3.
- Mk.15 (533 mm): The Mk.15 has a much higher maximum speed (83 km/h); but it has a lower maximum range (5.5 km) and has a much smaller explosive mass (224 kg TNT equivalence). With the Torpedo Mode modification installed on both, the Mk.15 has a higher maximum speed (62 km/h), but it has a lower maximum range (9.15 km).
Usage in battles
Two of the Mk.IX’s specifications are worth noting: the above-average 340 kg TNT warhead and the maximum range of 12.35 km with the Torpedo Mode modification installed. Other than this, the torpedo is unremarkable. The maximum range without the Torpedo Mode modification is 9.6, respectable but unremarkable. The maximum speeds, 67 km/h with the Torpedo Mode modification and 56 km/h without, are on the lower end, but there are many slower torpedoes.
For motor torpedo boats and other smaller vessels, the Mk.IX should be used without the Torpedo Mode modification, where the lower maximum range is insignificant in the often short-range engagements, and the higher maximum speed is helpful in making it more difficult for the enemy vessel to evade. On destroyers and cruisers, the Mk.IX should be used with the Torpedo Mode modification, since close-range encounters are much less common, and the increased maximum range provides more strategic usefulness, especially in Encounter and Enduring Confrontation game modes.
History
Designed in 1928 and entering production and service in 1930, the 21-inch Mark IX was a British surface ship torpedo with a diameter of 21 inches (53.3 cm), a length of 23 feet 10.5 inches (7.277 m), and weighed 3,732 pounds (1,693 kg). It carried a 340 kg TNT warhead. The Mark IX was the second British torpedo to be powered by the burner-cycle engine, the first being the previous 21-inch Mark VIII torpedo. It had two settings: high-speed at 36 knots (66.7 km/h) for 9.6 km, and low-speed at 30 knots (55.7 km/h) for 12.35 km.
Two improved versions of the Mark IX were also developed, Mark IX* and Mark IX**. The Mark IX* increased the range to 10.05 km at the high-speed setting and to 12.8 km at the low-speed setting. The Mark IX** further increased the speed and range for both settings: 41 knots (75.9 km/h) for 10.05 km, and 35 knots (64.8 km/h) for 13.7 km. It also changed the warhead to a smaller 327 kg TNT warhead, though this would be replaced by a 365 kg TNT warhead on later productions of the Mark IX**.
The Mark IX was used on Leander-class light cruisers and any succeeding cruiser classes, and it replaced the older 21-inch Mark V torpedoes on A-class and B-class destroyers, also seeing usage on succeeding destroyer classes.
