Mk.VIII (533 mm)

Description

The Mk.VIII torpedo is a British 21-inch (533 mm) torpedo mounted on many destroyers and motor torpedo boats in the British tech tree. Other 21-inch British torpedoes include the Mk.V (533 mm) and the Mk.IX (533 mm).

General info

The Mk.VIII torpedo has a diameter of 533 mm, a length of 6.579 m, and weighs 1,566 kg. Without the Torpedo Mode modification installed, it can travel at a maximum speed of 84 km/h for 4.57 km. With it installed, the maximum range is increased to 6.40 km, but the maximum speed is reduced to 76 km/h.

Torpedo Mode Specification Changes
Max Distance (m)	Max Speed (m/s)
+1830	-1

Effective damage

The Mk.IX torpedo carries a 340 kg TNT warhead, which is fairly middling 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

Compared to all other ship-launched torpedoes in the British tech tree:

• Mark XII: An 18-inch torpedo, the Mark XII has a lower maximum speed (69 km/h), has a 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 slightly lower maximum speed (74 km/h) and has a much lower maximum range (1.37 km).

• Mark XV: An improved Mark XII, the Mark XV has a larger explosive mass (385 kg TNT equivalence); but it has a lower maximum speed (61 km/h) and has a lower maximum range (3.2 km). with the Torpedo Mode modification installed on both, the Mark XV has a much lower maximum speed (54 km/h) and has a lower maximum range (5 km).

• Mk.V (533 mm): The earliest of the British 21-inch torpedoes, the Mk.V has a lower maximum speed (74 km/h) and has a smaller explosive mass (305 kg TNT equivalence). With the Torpedo Mode modification installed on both, the Mk.V has a much higher maximum range (12.35 km), but it has a much lower maximum speed (46 km/h).

• Mk.IX (533 mm): A further development of the 21-inch torpedo, the Mk.IX has a much higher maximum range (9.6 km) and has a larger explosive mass (340 kg TNT equivalence); but it has a lower maximum speed (67 km/h). With the Torpedo Mode modification installed on both, the Mk.IX has a much higher maximum range (12.35 km), but it has a much lower maximum range (56 km/h).

Compared to common torpedoes mounted on destroyers and cruisers among other nations:

• Mk.15 (533 mm): The Mk.15 has a higher maximum range (5.5 km); but it has a slightly lower maximum speed (83 km/h) and has a smaller explosive mass (224 kg TNT equivalence). With the Torpedo Mode modification installed on both, the Mk.15 has a much higher maximum range (9.15 km), but it has a lower maximum speed (62 km/h).

• G7a (533 mm): The G7a has a larger explosive mass (358.4 kg TNT equivalence) and has a higher maximum range (6 km); but it has a slightly lower maximum speed (81 km/h). With the Torpedo Mode modification installed on both, the G7a has a much higher maximum range (14 km), but it has a much lower maximum speed (56 km/h).

• 53-38 (533 mm): The 53-38 has a slightly lower maximum speed (82 km/h), has a lower maximum range (4 km), and has a smaller explosive charge (300 kg TNT equivalence). With the Torpedo Mode modification installed, the 53-38 has a much higher maximum range (10 km), but it has a much lower maximum speed (56 km/h).

• Type 93 Model 1, Mod 2 (610 mm): The Type 93 Model 1, Mod 2 has a higher maximum speed (91 km/h), has a much higher maximum range (20 km), and has a much larger explosive mass (627.2 kg TNT equivalence). There is no Torpedo Mode modification available for the Type 93 Model 1, Mod 2.

• Type 93 Model 3 (610 mm): The Type 93 Model 3 has a 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.

Usage in battles

The Mk.VIII is a fast torpedo, sporting an above-average top speed of 84 km/h with the Torpedo Mode modification and a top speed 76 km/h without. However, its maximum range is small, 4.57 km with and 6.4 km without the Torpedo Mode modification. Its warhead is also only average, at 327 kg TNT.

For motor torpedo boats and other smaller vessels, the Mk.VIII 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, the Mk.VIII 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, though in this aspect, its small range of 6.4 km leaves much to be desired.

Pros and cons

Pros:

• Above average maximum speeds

Cons:

• Short maximum range

History

The 21-inch Mark VIII torpedo was designed in 1925. It had a diameter of 21 inches (533 mm), a length of 21 feet 7 inches (6.579 m), weighed 1,566 kg, and carried a 340 kg TNT warhead. The Mark VIII was the first British torpedo to utilise the burner-cycle engine, an advancement in torpedo technology at the time. In the burner cycle engine, pressurized air was heated and combined with atomised fuel, and then injected and ignited into the combustion chamber at top dead centre (when the piston is furthest away from the crankshaft). Powered by this, the Mark VIII could maintain a speed of 40 knots (74.1 km/h) for 4.57 km.

An improved version Mark VIII** was also developed, which increased the top speed to 45.5 knots (84.3 km/h) and introduced a low-speed setting at 41 knots (75.9 km/h) for 6.4 km. As originally designed, the Mark VIII** carried a 327 kg TNT warhead, though this would be replaced by a 365 kg Torpex warhead in later productions.

The Mark VIII entered service and production in 1927. The Mark VIII** was the primary version used during World War II, mounted on motor torpedo boats and the O-class submarines, as well as any succeeding submarine classes. It remained in service within the Royal Navy as late as 1982, when HMS Conqueror sunk the Argentinian light cruiser ARA General Belgrano during the Falklands War, and would continue to remain in service with other minor navies even further.

Media

Excellent additions to the article would be video guides, screenshots from the game, and photos.

See also

• Mk.V (533 mm)
• Mk.IX (533 mm)

External links

• NavWeaps - WWII Torpedoes of the United Kingdom/Britain