MTB Vosper(2)

This page is about the British motor torpedo boat MTB Vosper(2). For other versions, see MTB Vosper (Family).

MTB Vosper(2)

MTB Vosper

ML 1383

MTB Vosper(2)

MTB Vosper

ML 1383

Britain

I Rank

Battle rating:

AB	RB	SB
1.7	1.7	1.7

Class:

Motor torpedo boat

Boat

Research:4 000

Purchase:2 100

Show in game

Description

The MTB Vosper 2 series is a rank I British motor torpedo boat with a battle rating of 1.7 (AB/RB/SB). It was introduced in Update 1.83 "Masters of the Sea" as part of the British fleet closed beta test. With the split of the naval tech trees in Update "New Power", MTB Vosper(2) was moved to the coastal fleet tech tree.

General info

Survivability and armour

Armourfront / side / back

Hull24 mm (wood)

Superstructure15 mm (wood)

Number of section3

Displacement38 t

Crew12 people

MTB Vosper(2) internals (starboard). Note the ammunition storage below the bridge.

Vosper 2 series has the following armour layout:

• 20 mm/70 Oerlikon Mk.II gun shield: 12.7 mm, hardened armour
• Hull: 24 mm, wood
• Superstructure: 15 mm, wood

While the gun shield may stop low-calibre machineguns, heavy machineguns and cannons will have no trouble with them at any range. The hull and superstructure will not stop any sort of gunfire.

The hull is split into three compartments. The first compartment starts at the bow and ends at the forward gun mount; the second ends in front of the aft gun mount, between the fuel tanks and the engines; and the third ends at the stern. Vosper 2 series can be hull-broken by any round with a large enough diameter and explosive mass. In general, this is limited to HE rounds greater with a diameter greater than or equal to 4 inches (102 mm) with an explosive mass greater than 1.5 kg. At Vosper 2 series' battle rating, there is no gun capable of hull-breaking her.

There is one ammunition storage that holds ammunition for both the primary armament and secondary armament. It is located directly below the bridge, just above the waterline. Destroying it will instantly destroy the boat.

Vosper 2 series has a crew complement of 12. With a stock crew, it is knocked out when 8 crew are lost; with an aced crew, this is increased to 9. Overall, the survivability is average.

Mobility

Speedforward / back

AB104 / 35 km/h

RB74 / 25 km/h

Mobility Characteristics
Game Mode	Upgrade Status	Maximum Speed (km/h)		Turn Time (s)	Turn Radius (m)
		Forward	Reverse
AB	Stock	76	26	~23.68	~47.11
	Upgraded	104	35	~16.33	~31.04
RB/SB	Stock	64	22	~26.53	~53.95
	Upgraded	74	25	~21.99	~43.75

Vosper 2 series has a displacement of 38 tons.

When moving forwards at high speeds, the bow will drift slightly to starboard without any player input. When moving backwards, the bow drifts slightly to port.

Modifications and economy

Repair costBasic → Reference

AB177 → 222

RB246 → 308

Total cost of modifications4 420

2 680

Talisman cost300

Crew training600

Experts2 100

Aces45

Research Aces110 000

Reward for battleAB / RB / SB

20 / 30 / 100 %

100 / 100 / 100 %

Modifications

Seakeeping	Unsinkability	Firepower
Dry-Docking Research: 220 Cost: 135 55 Rudder Replacement Research: 165 Cost: 100 45 Propeller Replacement Research: 370 Cost: 220 95 Engine Maintenance Research: 360 Cost: 220 95	Damage Control Division Research: 220 Cost: 135 55 Fire Division Research: 165 Cost: 100 45 Smokescreen Research: 165 Cost: 100 45 New Pumps Research: 360 Cost: 220 95	20 mm HE magazines Research: 220 Cost: 135 55 12.7 mm I Research: 220 Cost: 135 55 Auxiliary Armament Targeting Research: 165 Cost: 100 45 20 mm AP magazines Research: 165 Cost: 100 45 12.7 mm API Research: 165 Cost: 100 45 Primary Armament Targeting Research: 370 Cost: 220 95 Depth Charges Research: 370 Cost: 220 95 Artillery Support Research: 360 Cost: 220 95 Torpedo Mode Research: 360 Cost: 220 95

The recommended modification research order is:

1. Tool Set
2. Fire Protection System
3. 12.7 mm I belt or 20 mm HE
4. Smokescreen
5. Propeller Replacement
6. Artillery Support

After that, prioritize the rest of the seakeeping modifications first, then research the remaining modifications in whatever order you prefer.

Armament

Primary armament

Turret20 mm/70 Oerlikon Mk.II autocannon

Ammunition1800 rounds

Belt capacity60 rounds

Fire rate450 shots/min

Vertical guidance-10° / 60°

The primary armament consists of a single 20 mm/70 Oerlikon Mk.II mounted fore, with a maximum of 1,980 rounds of ammunition. Stock, the mount can traverse horizontally and vertically at a rate of 64°/s; with the "Primary Armament Targeting" modification installed, this is increased to 75°/s. The gun has a magazine capacity of 60 rounds and a cyclic rate of fire of around 450 rounds/min. With a stock crew, it can be reloaded in 5.2 seconds; with an aced crew, it can be reloaded in 4 seconds.

Primary armament guidance
Horizontal	Vertical
±180°	-10°/+60°

There are three ammunition types available:

• Universal: HEF-T · HEF-I · AP-T

• 20 mm HE: HEF-T · HEF-I · AP-T · HEF-I

• 20 mm AP: AP-T · AP-T · AP-T · HEF-I

Penetration statistics
Ammunition	Penetration @ 0° Angle of Attack (mm)
	10 m	100 m	500 m	1,000 m	1,500 m	2,000 m
Universal	35	33	26	21	18	15
20 mm HE	35	33	26	21	18	15
20 mm AP	35	33	26	21	18	15

The best ammunition for general use is the HE belt, due to it having the highest ratio of HE rounds to AP rounds, making it the most effective against both aircraft and the vast majority of surface targets. Because of this, the HE belt should be the main ammunition once it is unlocked. Additionally, the AP belt, with its higher amount of AP rounds, is better for dealing with armoured targets, so take a decent amount of these as well for specialized usage.

Secondary armament

Turret2 x 12.7 mm Vickers Mk.V machine gun

Ammunition4000 rounds

Belt capacity200 rounds

Fire rate600 shots/min

The secondary armament consists of two 12.7 mm Vickers Mk.V machineguns in a twin mount aft. There are 5,200 rounds of ammunition available for it, 2,600 rounds per gun. Stock, the mount can traverse horizontally and vertically at a rate of 64°/s; with the "Auxiliary Armament Targeting" modification installed, this is increased to 75°/s. Each gun has a belt capacity of 200 rounds and a cyclic rate of fire of about 600 rounds/min, though the gun on the gunner's right side fires slightly faster, around 685 rounds/min. With a stock crew, the guns can be reloaded in 13 seconds; with an aced crew, they can be reloaded in 10 seconds.

Secondary armament guidance
Horizontal	Vertical
±180°	-10°/+70°

There are three ammunition types available:

• Universal: T · AP · I

• 12.7 mm I: T · I · I · I · I

• 12.7 mm API: T · AP · I · AP

Penetration statistics
Ammunition	Penetration @ 0° Angle of Attack (mm)
	10 m	100 m	500 m	1,000 m	1,500 m	2,000 m
Universal	24	24	21	18	16	15
12.7 mm I	20	19	16	14	12	11
12.7 mm API	24	24	21	18	16	15

Of the belts, the I belt has a noticeably higher damage output than both the Universal and API belts, both of which are about the same in terms of damage. Because it lacks any armour-piercing rounds, the I belt has slightly less armour penetration than the other two belts, but in general, any armour that can stop the incendiary round will also stop be able to armour-piercing round. For the most effectiveness, take only the I belt once unlocked, and switch the secondary 40 mm 2pdr Rolls Royce cannon to deal with armoured targets.

Additional armament

Setup 12 x 533 mm Mk.VIII torpedo

Setup 24 x Mk.VII depth charge

Setup 32 x 533 mm Mk.VIII torpedo

4 x Mk.VII depth charge

Vosper 2 series has four possible loadouts:

1. 2x Mk.VIII torpedo
2. 4x Mk.VII depth charge
3. 2x Mk.VIII torpedo, 4x Mk.VII depth charge
4. Without load

Torpedoes

Vosper 2 series can carry two 533 mm Mk.VIII torpedoes. The torpedo tubes are located on either side of the bridge, pointing forwards with the nose angled outwards.

Torpedo characteristics
Torpedo Mode	Mass (kg)	Maximum speed in water (km/h)	Travel distance (km)	Depth stroke (m)	Arming distance (m)	Explosive type	Explosive mass (kg)	TNT equivalent (kg)
No	1566	84	4.57	1	50	TNT	327	327
Yes	1566	76	6.40	1	50	TNT	327	327

The Torpedo Mode modification is available as a rank IV modification. Installing it will give the following changes:

Torpedo mode specification changes
Max Distance (m)	Max Speed (m/s)
+1830	-2

It's best to always keep Torpedo Mode uninstalled. The maximum speed of a torpedo is much more valuable in coastal battles than its maximum range. Coastal fleet maps are also small enough that the decreased range with Torpedo Mode installed isn't much of an issue.

In RB, always set the depth stroke to the minimum 1 m setting. This is because many vessels that MTB-1 1 series can face will not have a deep enough draught to fuse the torpedo at a depth stroke setting of 4 m. In AB, depth stroke is automatically set to the most optimal setting.

When using torpedoes, be aware that unless they are already launched, the torpedoes have a very high chance to detonate when shot at, instantly destroying the boat. To avoid this, fire the torpedoes immediately after spawning in—as well as after any subsequent reloads in AB—or simply don't take them at all. Torpedoes are a situational weapon, so it's largely down to personal preference whether or not to take them.

Depth Charges

Mk.VII depth charges numbered according to their drop order (click to view a larger image).

The Mk.VII depth charges are carried around the bridge area, three on each side. They are dropped one at a time in the following order:

1. Port, foremost
2. Starboard, foremost
3. Port, aftmost
4. Starboard, aftmost

Before spawning, the detonation time delay can be set anywhere between 3 seconds and 10 seconds.

Depth charge characteristics
Mass (kg)	Explosive type	Explosive mass (kg)	TNT equivalent (kg)	HE armour penetration (mm)	Armoured vehicle destruction radius (m)	Fragment dispersion radius (m)
196	TNT	130	130	101	8	122

There is almost no practical reason to use depth charges on any naval vessel in the game. Although they usually result in a one-hit kill if used properly, they are extremely situational, requiring the player to close to point-blank ranges to even use them. In almost every case, anytime a depth charge could be used, the guns or torpedoes can be used instead to greater effect. In fact, depth charges tend to actually be a liability in battle, since they essentially act as exposed ammo racks before they're dropped. Like torpedoes, they have a relatively high chance to detonate when shot at, instantly destroying the boat.

Despite this, some success can be had in dropping them either next to or in front of a large, slow target. If dropping them next to the target, remember the depth charge drop order, since it's most likely that only the depth charges dropped on the side closest to the enemy will deal any damage. If dropping in front of the target, rush in from the sides as quickly as possible and drop them all at once directly in front of the target. For both cases, set the depth charge time delay to the minimum 3 seconds, since any higher time delay will only allow the depth charge to sink further away from the target, giving them more time to move out of the way. Again, using depth charges is extremely situational, and they will only be a liability the vast majority of the time, so take them at your own discretion.

Usage in battles

Between the primary and secondary armaments, the secondary twin 12.7 Vickers Mk.V machine guns are actually much more effective than the primary single 20 mm/70 Oerlikon Mk.II. Using 12.7 mm I belt, the two machine guns together have a much greater damage output than the cannon, and with their larger belt capacity, they are also able to sustain fire for much longer periods of time before needing to reload. However, this does come at the cost of a longer reload and the fact that they are mounted aft, preventing them from firing in a ~46° arc forwards. Conveniently, the disadvantages of the Vickers Mk.V machine guns are the advantages of the Oerlikon Mk.II cannon, and vice versa: the Oerlikon Mk.II is mounted on the bow and has a quicker reload, but it is weaker in terms of damage. The primary and secondary armament nicely complement each other, and to fully make use of Vosper 2 series, both must be used together.

Since the Vickers Mk.V machine guns have the best damage output, switch to manual control of the secondaries and use these as the primary weapon. During their reloads, or in case they get knocked out, switch back to the Oerlikon Mk.II to continue the fight. The main disadvantage of heavy machine guns like the Vickers Mk.V is that they generally have a very long reload. By switching back to the Oerlikon Mk.II during reloads, Vosper 2 series can mostly circumvent this problem, allowing it to continue sustaining fire through about 70-80% of the reload of the machine guns, depending on crew skills. With this to fall back on, Vosper 2 series can afford to be more aggressive than most other vessels at this tier. However, to fully make use of this, the Oerlikon Mk.II should have a full magazine at all times, which can only be guaranteed by disabling the AI gunners. While this does greatly increase surface capabilities, it leaves Vosper 2 series open to aerial attacks, so always look out for enemy aircraft, and reenable the AI gunners to target aircraft if necessary. When targeting aircraft, the Vickers Mk.V machine guns tend to be more effective than the Oerlikon Mk.II due to their volume of fire, so in this case, switch back to the cannon to give control of the machine guns to the AI gunners.

An alternative to this is to be proactive with the reloads like with other vessels. After engagements, if there isn't much ammunition left in the Vickers Mk.V magazines—less than about 100 rounds between both guns—retreat to cover, and then fire off any remaining ammunition to reload in safety. When playing like this, the Oerlikon Mk.II is more like a last resort weapon to switch to in a pinch. Since you're not constantly relying on it, it doesn't need to be full at all times, which frees it up for use by the AI gunners in combat. While this is certainly the safest approach to playing Vosper 2 series, it doesn't take advantage of its strengths as much as the first playstyle does. That said, both are effective in their own right, so it's down to personal preference which way to play. Whichever playstyle you prefer, remember to be flexible and always be prepared to switch to the other weapon.

Pros and cons

Pros:

• Strong secondary armament: great damage output
• Good manoeuvrability
• Good torpedoes: above-average maximum speed and explosive charge

Cons:

• Long secondary armament reload

History

During the 1930s, the Admiralty began to reestablish the coastal boat flotillas it once commanded during the First World War. British boatbuilding company Vosper & Company competed for the contract but lost both times in 1935 and 1936, the lucrative contract to build the first coastal boats since WWI going instead to their rival, British Power Boat Company. In response to this, Vospers developed plans for a faster and more seaworthy design than that of their rivals'. In the following months, Vospers proposed their new design to the Admiralty multiple times, but ultimately, they could not secure a contract to build a prototype. Around this time, though, the Admiralty officials had unofficially suggested that future contracts would only be awarded for vessels that could surpass 40 knots in speed and that were armed with two 21-inch torpedoes as well as an assortment of light anti-aircraft guns. Additionally, it was known from previous specifications that the Admiralty wanted a vessel capable of operating in open waters in at least Force 5 winds and that was fast enough to cross the English Channel during the night. With these unofficial specifications, Vospers preemptively began development on a new vessel as a private venture at the company's own expense.

Immediately, it was decided that the private venture vessel had to be larger than the existing 60 ft British Power Boat MTB in order to meet the specifications. Additionally, engines more powerful than the Napier Sea Lion engines used in the BPB design were required. With none available domestically, Vospers looked to the Asso 1000 engine by Italian manufacturer Isotta-Fraschini. Though in limited supply, the Asso 1000 was specifically designed for marine craft and provided the necessary power: 1150 bhp at 1500 rpm maximum and 950 bhp at 1660 rpm continuous. In late 1936, Vospers completed their design. It called for three Asso 1000 engines and two in-house 75 bhp auxiliary engines, the latter of which could be coupled to the outer shafts to give a total maximum power of 3600 bhp. The hull-form was a hard chine planing design and was 69½ ft in length with a displacement of about 33 tons. The prototype was laid down before the end of the year and completed in May 1937.

Upon completion, the prototype underwent internal trials where she achieved a top speed of 47.8 knots unloaded and 43.7 knots loaded. Satisfied with these results, Vospers presented the prototype to the Admiralty for official trials against the 60 ft British Power Boat MTB. The prototype fared favorably, and after much deliberation, the Admiralty decided to purchase the vessel from Vospers. She was commissioned in May 1938 as MTB 102 and sent to HMS Vernon for further evaluation. Up to this point, MTB 102 had not actually been fitted with torpedoes, so during her time at HMS Vernon, many torpedo configurations were tested. These included the tried-and-true yet outdated stern projection systems, as seen on the 60 ft British Power Boat MTB and earlier WWI designs, as well as a unique arrangement of a single launcher in the stem of the hull with a reload carried internally. These all had their own issues, and none were found to be satisfactory. Ultimately, it was decided that MTB 102 should have two torpedo tubes mounted on either side of the bridge, pointed forwards with the nose angled outwards, an uncommon configuration for the time. Around this time, the gun armament had also not yet been decided, so various configurations were also experimented with, including combinations of 0.303 in and 0.50 in machine guns and a 20 mm autocannon.

Impressed with MTB 102, the Admiralty placed an order for four more vessels on 15th August 1938, Vospers' first-ever Admiralty contract. These vessels, and any ordered after, all shared the same overall design as MTB 102, although with several minor changes such as the hull being lengthened to 70 ft 3¼ in. After 1940, with the entrance of Italy into the war, Isotta-Fraschini engines could no longer be obtained, and subsequent boats had to be fitted with much weaker American Hall Scott engines—only 1800 bhp total—as a stopgap measure until they could be upgraded with more powerful Packard engines, although this wasn't until 1941 as supply was limited. Of the 32 planned 70 ft Vosper MTBs, 28 were completed and are as follows:

• MTBs 20-23: Ordered 15th August 1938, all were completed by December 1939. MTBs 20, 21, and 23 were sold to the Romanian Navy. MTB 22 served with the 4th MTB Flotilla. She survived to the end of the war and was sold in 1945.

• MTBs 29-30: Ordered on 8th September 1938—including a Thornycroft design, MTB 28—as replacements for the three boats sold to Romania, all were completed by July 1940. Both MTB 29 and 30 served with the 4th MTB Flotilla. MTB 29 was lost in a collision with a German E-boat on 6th October 1942, and MTB 30 struck a mine and was lost on 18th December 1942.

• MTBs 31-40: Ordered on 27th September 1939, six were completed by May 1941. MTBs 33, 37, 39, and 40 were bombed by German aircraft while under construction in 1940-41. The completed boats survived to the end of the war and were sold in 1945-46.

• MTBs 57-66: Ordered on 26th February 1940, all were completed by April 1942. MTB 61 was stranded during an attack on 9th May 1943, and MTBs 63 and 64 were lost after collisions with friendly MTBs on 2nd April 1943. The remaining boats were sold in 1944.

• MTBs 69-70: Ordered in April 1940, both were completed by June 1940 and received only two engines. Both were stationed at HMS Beehive, Felixstowe. They both survived to the end of the war and were sold in 1945-46.

• MTBs 218-221: Ordered on 7th December 1940, all were completed by September 1941. MTB 218 struck a mine and was lost on 18th August 1942, and MTB 220 was sunk by German E-boats on 13th May 1942. MTBs 219 and 221 survived to the end of the war. MTB 221 was sold in 1945, and MTB 219 was transferred to the Sea Cadet Corps at Staines in 1945 and was converted to a houseboat in 1948.

The 70 ft Vosper MTB design continued to receive many improvements and modifications order-to-order and would lead to the development of the 72 ft Vosper MTB and 73 ft Vosper MTB.

Media

Skins

• Skins and camouflages for the MTB Vosper(2) from live.warthunder.com.

See also

• MTB Vosper (Family)
• MTB Vosper
• GIS 811

External links

• [Coastal Forces Veterans] Boat Database
• [ww2ships.com] 70' Vosper Motor Torpedo Boat
• [Unit Histories] Royal Navy Coastal Forces 1940-1945
• [naval-history.net] British vessels lost at sea in World War 2 - MGB, MTB, SGB, ML, etc - originally published in British Vessels Lost at Sea, 1935-45, His Majesty's Stationary Office, 1947

Bibliography

• Lambert, J., & Ross, A. (1993). Allied Coastal Forces of World War II Volume II: Vosper MTBs & U.S. Elcos (pp. 21-32). London, England: Conway Maritime Press. ISBN 0-85177-602-7.