MGB-75

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MGB-75
uk_71ft_mgb.png
GarageImage MGB-75.jpg
MGB-75
Purchase:1 000 Specs-Card-Eagle.png
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Description

The 71 ft MGB-75 is a premium rank II British motor gun boat with a battle rating of 2.0 (AB) and 2.3 (RB/SB). It was introduced in Update 1.91 "Night Vision". Originally a rank I vessel, with the split of the naval tech trees in Update "New Power", MGB-75 was moved to rank II in the coastal fleet tech tree.

General info

Survivability and armour

Armourfront / side / back
Hull40 mm (wood)
Superstructure15 mm (wood)
Number of section3
Displacement52 t
Crew12 people

MGB-75 has the following armour layout:

MGB-75 internals (starboard side).

Like most coastal vessels, MGB-75 has no practical armour. The gunshields are largely superficial; while they may stop low-calibre machine guns, heavy machine guns and cannons will easily penetrate them at any range. The hull and superstructure are unarmoured and will not stop any sort of gunfire.

The hull is split into three hull sections. Starting from the bow and working towards the stern, the first section starts at the bow and ends just in front of forward gun; the second ends after the bridge, forward of the engines; and the third ends at the stern.

Any round with a large enough diameter and explosive mass can hull break MGB-75. In general, this is limited to HE rounds with a diameter greater than 4 inches (102 mm) and with an explosive mass greater than 1.5 kg. At MGB-75's own battle rating, the only guns that can hull break her are:

There are two ammunition storages. The first storage, which holds ammunition for the primary armament, is located in the hull above the waterline, below and slightly in front of the forward gun turret. The second storage, which holds ammunition for both the secondary and AA armament, is located above deck, in the superstructure in front of the aft gun turret. Destroying either will instantly destroy MGB-75. Since it is located in the superstructure, the second ammunition storage is particularly susceptible to detonation by random gunfire or artillery.

MGB-75 has a crew complement of 12. With a stock crew, MGB-75 is knocked out when 8 crew are lost; with an aced crew, this is increased to 9. Because of the exposed ammunition storages, overall survivability is below-average.

Mobility

Speedforward / back
AB104 / 29 km/h
RB78 / 22 km/h
Mobility Characteristics
Game Mode Upgrade Status Maximum Speed (km/h) Turn Time (s) Turn Radius (m)
Forward Reverse
AB Stock 77 21 ~29.18 ~55.47
Upgraded 104 29 ~19.63 ~34.71
RB/SB Stock 67 19 ~32.4 ~64.46
Upgraded 78 22 ~26.3 ~50

MGB-75 has a displacement of 51.5 tons.

When moving forwards at high speeds, the bow will lift out of the water. This creates a blind spot where the 40 mm 2pdr QF Mk.IIc is unable to depress far enough to hit the waterline. This blindspot extends ~400 m in front of the boat and ~45° to either side.

Modifications and economy

Repair cost
AB465 Sl icon.png
RB683 Sl icon.png
Crew training4 800 Sl icon.png
Experts32 000 Sl icon.png
Aces250 Ge icon.png
Research Aces440 000 Rp icon.png
Reward for battleAB / RB / SB
Talisman.png 2 × 70 / 80 / 50 % Sl icon.png
Talisman.png 2 × 124 / 124 / 124 % Rp icon.png
Modifications
Seakeeping Unsinkability Firepower
Mods new ship hull.png
Dry-Docking
Mods new ship rudder.png
Rudder Replacement
Mods new ship screw.png
Propeller Replacement
Mods new ship engine.png
Engine Maintenance
Mods ship damage control crew.png
Damage Control Division
Mods ship fire control crew.png
Fire Division
Mods engine smoke screen system.png
Smokescreen
Mods new ship pumps.png
New Pumps
Mods new aa caliber turrets.png
Anti-Air Armament Targeting
Mods ammo.png
40mm_qf_mkxv_he_ammo_pack
Mods ammo.png
20 mm HE magazines
Mod arrow 0.png
Mods new aux caliber turrets.png
Auxiliary Armament Targeting
Mods ammo.png
40mm_qf_mkxv_ap_ammo_pack
Mods ammo.png
20 mm AP magazines
Mods new main caliber turrets.png
Primary Armament Targeting
Mods ship rangefinder.png
Improved Rangefinder
Mods depth charge.png
Depth Charges
Mods ship art support.png
Artillery Support

As a premium vehicle, all modifications are unlocked for free.

Armament

Primary armament

Turret40 mm 2pdr QF Mk.IIc automatic cannon
Ammunition2240 rounds
Belt capacity56 rounds
Fire rate200 shots/min
Vertical guidance-5° / 70°

The primary armament consists of a single 40 mm 2pdr QF Mk.IIc cannon mounted forwards in front of the bridge. Stock, the mount can traverse horizontally at a rate of 34°/s and vertically at a rate of 21°/s; with the "Primary Armament Targeting" modification installed, this is increased to 40°/s and 25°/s respectively. With a full ammunition load, there are 2,240 rounds of ammunition, or 40 magazines, available for the mount. The gun has a magazine capacity of 56 rounds and a cycle rate of fire of 200 rounds/min. With a stock crew, it can be reloaded in 7.8 seconds; with an aced crew, this is decreased to 6 seconds.

Primary armament guidance
Horizontal Vertical
±180° -5°/+70°

There are three ammunition types available:

  • Universal: HEF · AP-T · HEF · AP-T
  • 40 mm HE: HEF · HEF · HEF · AP-T
  • 40 mm AP: AP-T · AP-T · AP-T · HEF

Penetration statistics
Ammunition Penetration @ 0° Angle of Attack (mm)
10 m 100 m 500 m 1,000 m 1,500 m 2,000 m
HEF 3 3 3 3 3 3
AP-T 60 57 48 39 32 26
Shell details
Ammunition Velocity
(m/s)
Projectile
mass (kg)
Fuse delay
(m)
Fuse sensitivity
(mm)
Explosive mass
(TNT equivalent) (g)
Ricochet
0% 50% 100%
HEF 701 0.82 0 0.1 71 79° 80° 81°
AP-T 701 0.91 - - - 47° 60° 65°

The best ammunition type is 40 mm HE, since it has the highest ratio of HE rounds to AP rounds, making it the most effective against both aircraft and the vast majority of surface targets. Take mostly 40 mm HE along with a several magazines of 40 mm AP for armoured targets.

Secondary armament

Turret2 x 20 mm/70 Oerlikon Mark V autocannon
Ammunition3600 rounds
Belt capacity60 rounds
Fire rate450 shots/min

The secondary armament consists of two 20 mm/70 Oerlikon Mark V cannons in a twin mount aft. Stock, the mount can traverse horizontally at a rate of 51°/s and vertically at a rate of 43°/s; with the "Secondary Armament Targeting" modification installed, this is increased to 60°/s and 50°/s respectively. With a full ammunition load, there are 3,600 rounds of ammunition, or 60 magazines, available for the mount. Each gun has a magazine capacity of 60 rounds and a cycle rate of fire of 450 rounds/min, though the gun on the gunner's left side fires at a slightly faster rate, around 485 rounds/min. With a stock crew, the mount can be reloaded in 10.4 seconds; with an aced crew, this is decreased to 8 seconds.

Secondary 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
HEF-T 2 2 2 2 2 2
AP-T 34 32 24 17 12 8
HEF-I 2 2 2 2 2 2
Shell details
Ammunition Velocity
(m/s)
Projectile
mass (kg)
Fuse delay
(m)
Fuse sensitivity
(mm)
Explosive mass
(TNT equivalent) (g)
Ricochet
0% 50% 100%
HEF-T 830 0.12 0 0.1 6.57 79° 80° 81°
AP-T 830 0.12 - - - 47° 60° 65°
HEF-I 830 0.12 0 0.1 11.17 79° 80° 81°

The best ammunition type is the 20 mm HE belt, since it has the highest ratio of HE rounds to AP rounds, making it the most effective against both aircraft and the vast majority of surface targets. The Universal belt is a direct downgrade to the 20 mm HE belt in terms of damage, and the 20 mm AP belt isn't really worth taking due to its relatively low armour penetration. To deal with armoured opponents, use the primary 40 mm 2pdr QF Mk.IIc instead. Take only 20 mm HE.

Anti-aircraft armament

2 х Turret2 x 7.72 mm Lewis machine gun, pattern 1916
Ammunition3880 rounds
Belt capacity97 rounds
Fire rate551 shots/min
Main article: Lewis 1916 (7.72 mm)

The anti-aircraft armament consists of four 7.72 mm Lewis 1916 machine guns in two twin mounts, one on either side of the bridge. A total of 7,760 rounds of ammunition, or 80 magazines, are carried for both mounts, 1,940 rounds, or 20 magazines, per gun. Each gun has a magazine capacity of 97 rounds and a cycle rate of fire of 550 rounds/min. With a stock crew, the mount can be reloaded in 18.2 seconds; with an aced crew, this is decreased to 14 seconds. Horizontal and vertical traverse rates are not stated in-game.

Msg-info.png Turrets are named sequentially, clockwise, starting at the bow
Anti-aircraft armament guidance
No.1 Turret (starboard) No.2 Turret (port)
Horizontal Vertical Horizontal Vertical
-45°/+170° -5°/+60° -170°/+45° -5°/+60°

Ammunition types cannot be selected for the anti-aircraft armament on MGB-75. Belt composition and penetration statistics are not stated in-game.

Additional armament

Setup 12 x Mk.VII depth charge
Main article: Mk.VII depth charge

MGB-75 has two possible loadouts:

  1. Without load
  2. 2x Mk.VII depth charge

Depth charges

Mk.VII depth charges numbered according to their drop order.

The Mk.VII depth charges are carried amidships, one on either side of the bridge next to the twin 7.72 mm Lewis 1916 machine guns. They are dropped one at a time in the following order:

  1. Starboard
  2. Port

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 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. They can be shot at, and if destroyed, they have a chance to detonate, 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

MGB-75 is plagued by two huge weaknesses that limit her offensive and defensive capabilities. The first of these is that the hull planes when moving at high speeds, lifting the bow out of the water. This normally isn't an issue for most boats, but on MGB-75, it creates a huge blindspot extending ~400 m in front of the boat and ~45° to either side where the primary 40 mm 2pdr QF Mk.IIc is unable to depress far enough to hit the waterline. Because of this, the 40 mm cannon is completely unable to hit opponents within ~250-300 m, depending on the target's height.

The second weakness is the aft ammunition storage, which is located above deck in the superstructure. Normally, ammunition detonations aren't much of a factor in a coastal vessel's effectiveness. This is because ammunition storages are typically located in the hull and placed a good enough distance away from the outside of the boat. The internal space acts like a buffer, with the hull preventing any HE rounds from reaching the ammunition storage. However, on MGB-75, there is no internal space buffer for the aft ammunition storage, making ammunition detonations very common. Unfortunately, since this ammo rack is tied to both the secondary and anti-aircraft armament, and since the ammunition load for the anti-aircraft armament cannot be selected, there is no easy way to remove this ammunition storage.

To best make use of MGB-75, both of these weaknesses need to be taken into account. Because of the blindspot, stick to mid-range or long-range engagements. Being at long range also has the added benefit of making it more difficult for enemies to specifically target the aft ammunition storage, but as with most vessels, it's best to not be hit in the first place, so stay on the move and make use of cover wherever possible. If the need to fight at close-range arises, switch to the secondary 20 mm/70 Oerlikon Mark V cannons. These guns are mounted aft, so they cannot target anything in a ~45° arc forwards, ~75° when moving. However, unlike the 40 mm cannon, the 20 mm cannons can at least target close-range opponents at all speeds. MGB-75 is much weaker in close-range engagements, though, since the 20 mm cannons have a much longer reload, and they require turning the hull to aim, so avoid close-range engagements as much as possible.

Because of the aft ammunition storage, opponents armed with 3 or 4-inch cannons should be the biggest priority, since a single hit with one of these guns anywhere near the ammunition storage is enough to detonate it. Artillery strikes, friendly or not, are also a major hazard for MGB-75. Keep away from capture points and narrow passageways where artillery is common, and the artillery strike warning appears, leave the area as soon as possible. Lastly, the ammunition storage is very susceptible to aircraft attacks due to its location. Keep the AI gunners targeting aircraft, but don't solely rely on them. Instead, use them as a warning for any aircraft in the area, and manually shoot them down if necessary.

Pros and cons

Pros:

  • Powerful primary and secondary armaments

Cons:

  • Blind spot directly in front when moving at high speeds
  • Long reloads for both primary and secondary armaments
  • Exposed ammunition storage

History

By early 1941, many of the British Power Boat Company (BPB) 60-foot, 63-foot, and 70-foot boats had been completed and were in Royal Navy Coastal Forces service, and already, their weaknesses began to show. The boats were small and lightly constructed, and the living conditions for the crew were cramped. Additionally, because of their underpowered engines, these boats were quite slow. While their low top speed was certainly acceptable for anti-submarine work, as they were initially built to perform, it was insufficient by 1941 as most of the boats had been converted into motor gun boats by this point. Thus, in 1941, BPB began plans for a successor to their previous lines of boats.

The new design had a length of 71 ft 9 in (21.9 m), a beam of 20 ft 7 in (6.3 m), and a draught of about 4 f 3 in (1.3 m). It was powered by three Packard petrol engines driving three shafts, allowing it to achieve a top speed of 42 knots. After their introduction, the BPB 71'9" boats formed the bulk of Coastal Forces' MGB fleet until the introduction of the larger and more heavily-armed Fairmile D boats. Later in the war, many BPB 71'9" boats would receive a pair a 18-inch torpedo tubes and refitted for motor torpedo boat duty. In total, 96 boats were built:

  • MGBs 74-81: Ordered in November 1940 as MA/SBs, all were completed in 1942 as MGBs. Any surviving boats by September 1943 were refitted with a pair of 18-inch torpedo tubes and redesignated as MTBs 412-416. Any of the boats that survived the war were disposed of in October 1945.
  • MGBs 107-119: Ordered in November 1940 as MA/SBs, the order was canceled in March 1941. They were subsequently reordered in February 1942, with all completed in 1942 as MGBs. Any surviving boats by September 1943 were refitted with a pair of 18-inch torpedo tubes and redesignated as MTBs 417-418 and 430-438. Any of the boats that survived the war were disposed of either in March 1945 or in October 1945.
  • MGBs 120-130: Ordered in May 1942 as MGBs, all were completed in 1943. All boats were refitted in September 1943 with a pair of 18-inch torpedo tubes and redesignated as MTBs 439-449. Most of the boats that survived the war were disposed of in October 1945.
  • MTBs 450-489: Ordered as MGBs, all were completed between 1943-1945 as MTBs. Any of the boats that survived the war were disposed of at various dates or used as controlled targets.
  • MTBs 490-500: ordered as MTBs, all were completed between 1944-1945. Any of the boats that survived the war were disposed of at various dates or used as controlled targets, with the exception of MTB-496 and MTB-498. These were refurbished in 1949 and renumbered MTB-1596 and MTB-1598 to form the Proud-class along with MTBs 1505-1509, MTB-1519, and MTB-1522. They were given the names "Proud Patriot" and "Proud Patroller", respectively. The Proud-class boats were all sold in June 1958.
  • MTBs 501-509: ordered as MTBs, all completed in 1945. All of the boats survived the war. MTBs 501-504 were sold or disposed of at various dates. MTBs 505-509 were refurbished in 1949 and renumbered MTBs 1505-1509 to form the Proud-class along with MTB-1596, MTB-1598, MTB-1519, and MTB-1522. They were given the names "Proud Fusilier", "Proud Grenadier", "Proud Guardsman", "Proud Highlander", and "Proud Knight", respectively. The Proud-class boats were all sold in June 1958.
  • MTBs 519-522: ordered as MGBs, all completed in 1946 as MTBs. With the exception of MTB-520, they were refurbished in 1949 and renumbered MTB-1519, MTB-1521, and MTB-1522. MTB-1519 and MTB-1522 formed the Proud-class along with MTBs 1505-1509, MTB-1596, and MTB-1598. They were given the names "Proud Lancer" and "Proud Legionary", respectively. The Proud-class boats were all sold in June 1958.

MGB-75 was part of the original order placed in November 1940. She was ordered as a motor anti-submarine boat but was completed on 8th May 1942 as a motor gun boat. MGB-75 was commanded by the following:

  • T/Lt. L.G.R. Campbell, RNVR: October 1942 to February 1943
  • T/S.Lt. F.J. Head, RNVR: April 1943 to June 1943
  • T/S.Lt. W.G.L. Salmon, RNVR: From June 1944 onwards

MGB-75 served as part of the 6th MGB Flotilla with HMS Beehive at Felixstowe through 1943. In September 1943, MGB-75 received her refit and was redesignated as MTB-413. Through 1944, MTB-413 served as part of the 1st MTB Flotilla at Portsmouth. MTB-413 survived the war and was disposed of in October 1945.

Media

Skins

See also

External links

Bibliography

  • Konstam, Angus (2010). British Motor Gun Boat 1939–45. Osprey Publishing Ltd. ISBN 978-1-84908-077-4.


British Power Boat Company
Motor Torpedo Boat (MTB) 
60 ft British Power Boat MTB  MTB-1(1) · MTB-1(2)
Motor Gun Boat (MGB) 
70 ft British Power Boat MGB  MGB-61
71 ft British Power Boat MGB  MGB-75

Britain boats
Motor torpedo boats  Brave Borderer · Dark Aggressor · Dark Aggressor TD · Fairmile D (617) · Fairmile D (697) · Fairmile D (5001) · HMS Gay Archer
  MTB-1(1) · MTB-1(2) · MTB Vosper · MTB Vosper(2) · MTB-422
Motor gun boats  Dark Adventurer · Fairmile A (ML100) · Fairmile B (ML345) · Fairmile C (312) · Fairmile C (332) · Fairmile D (601) · Fairmile H LCS(L)(2)
  HMAS Arrow · HMAS Fremantle · MGB-61 · MGB-75 · ML 1383 · SGB Grey Fox · SGB Grey Goose
Gunboats  HMS Spey

Britain premium ships
Motor torpedo boats  MTB-1(2) · MTB-422 · Fairmile D (5001) · HMS Gay Archer
Motor gun boats  MGB-75 · SGB Grey Goose
Gunboats  HMS Spey
Sub-chasers  LÉ Orla
Frigates  HMS Whitby
Destroyers  HMS Montgomery · HMS Valhalla · HMS Verdun · ORP Garland · HMS Jervis · HMCS Haida · HMS Mohawk · HMS Cadiz · HMS Diamond
Light cruisers  HMS Belfast
Battleships  HMS Iron Duke