- 1 Description
- 2 General info
- 3 Armaments
- 4 Usage in battles
- 5 History
- 6 Media
- 7 See also
- 8 External links
The Cruiser tank A.C. Mark IV, also known as the AC IV Thunderbolt or the AC IV Sentinel, is a premium rank III British medium tank with a battle rating of 5.3 (AB/RB/SB). It was released some time after Update 1.55 "Royal Armour". Armed with a 17-pounder gun, it has a high firepower for the battle rating it is in, able to effectively fight any other tanks at the battle rating. The Thunderbolt is also a small and manoeuvrable tank able to exploit harsh terrain to target the enemy.
The AC IV is a well-rounded tank with superior armour layout compared to other British tanks at its BR; it can occasionally bounce shells from Tigers and Panthers if lucky. It is a relatively small medium tank in comparison to the common mainstay of the other countries, especially when compared to the American Sherman tanks. The Sentinel also has a good manoeuvrability and power-to-weight ratio for the propulsion, able to accelerate to its max speed of roughly 30 km/h quickly and stay there on stable terrain. The tank has a great advantage of a decent reverse speed in comparison to other medium tanks of its calibre, with a reverse speed almost the same speed as forward. The addition of the 17-pounder gun also gives this tank a whopping high firepower for the size, so it can stand a chance against tanks of the same tier despite being out of the league in terms of armour.
The tank in the game is the version planned for serial production, so it has the hull of the AC III; unlike the actual prototype design developed, which used the hull from the AC I version.
Survivability and armour
The AC IV Thunderbolt is one of the few British tanks at this BR with sloped armour rather than the traditional boxy armour found in other British tanks. Its armour has a high tendency to bounce shells. This is obvious with the extreme slope on the from of the tank, and turret design. The armour itself is not thick, but thanks to the angle of it this tank can be very fierce competition to enemy vehicles. Although the armour is superior to that of other British tanks, it is not recommended to rely on it too heavily. Other nations, particularly the Germans, have no trouble penetrating the tank from any range. Because the crew compartment is relatively cramped, any penetrating shots can be fatal. The side armour on the Sentinel is extremely weak and vulnerable to SPAA flanking.
- Cast homogeneous armour
- Rolled homogeneous armour (Hull roof)
|Hull|| 50.8 mm (66-67°) Frontal glacis
50.8 mm (30°) Driver's port
50.8 mm (7-68°) Lower glacis
|44.45 mm (0-12°)|| 22.22 mm (78°) Top
44.45 mm (21-52°) Bottom
|Turret|| 63.5 mm (4-47°) Turret front
25.4-63.5 mm (1-68°) Gun mantlet
|63.5 mm (0-88°)||63.5 mm (1-53°)||35 mm|
|Cupola||63.5 mm||35 mm|
- Suspension wheels and bogies are 20 mm thick, tracks are 20 mm.
- The rear bottom area has a track placed there, providing 20 mm of extra armour.
- The commander cupola is extended outwards from the left side of the turret, creating a vulnerable unsloped area vulnerable to weaker guns.
The AC.IV has an overall good mobility, with an acceptable reverse speed not found in other British tanks (e.g., Challenger, Comet, etc.). The manoeuvrability in soft terrain can be significantly reduced and can feel sluggish.
|Game Mode||Max Speed (km/h)||Weight (tons)||Engine power (horsepower)||Power-to-weight ratio (hp/ton)|
Modifications and economy
The classic Ordnance QF 17-pounder is a very powerful gun: its performance against Tiger I and Panthers is very consistent and satisfactory. The Sentinel offers a smooth gun handling, with a good turret traverse speed and a good gun elevation speed. It has an excellent gun depression of -10 degrees and offers a small silhouette when hull down, comparable to the Comet. Because British tanks do not have access to APHE shells, any shot fired must be accurate; always aim for crew compartments and vital components of enemy tanks.
|76 mm QF 17-pounder||Turret rotation speed (°/s)||Reloading rate (seconds)|
|Ammunition|| Type of
|Penetration @ 0° Angle of Attack (mm)|
|10 m||100 m||500 m||1,000 m||1,500 m||2,000 m|
|Ammunition|| Type of
| Fuse delay
| Fuse sensitivity
| Explosive mass
(TNT equivalent) (g)
|Smoke shell characteristics|
| Screen radius
| Screen deploy
| Screen hold
| Explosive mass|
(TNT equivalent) (g)
|17pdr Shell SS Mk.1||229||8.44||13||5||20||50|
|50||45 (+5)||39 (+11)||35 (+15)||31 (+19)||25 (+25)||19 (+31)||15 (+35)||11 (+39)||1 (+49)||No|
- Racks disappear after you've fired all shells in the rack.
|Which ones||Default magnification||Maximum magnification|
|Main Gun optics||x1.85||x3.5|
Does not have improved zoom like the other rank III British tanks of similar BR, thus has worse zoom than many of its opponents, which may have variable zooms up to X5. Do not unnecessarily provoke German SPGs, as they have superior optics and are unlikely to miss.
In full up-tier, do not let Japanese medium tanks (e.g. ST-A1) get an upper hand at all costs, as they have optics eclipsing these entirely and can easily snipe A.C.IV from 2 km away, with accuracy modifications.
There is only one 7.7 mm coaxial MG with a very slow rate of fire, and no roof-mounted MG to defend against incoming planes. The small calibre of the Vickers machine gun makes it largely ineffective against all armoured vehicles but the ones with an open compartment. It still can be used to ping targets as a rangefinding help. While the belt capacity of the machine gun is adequate, its rate of fire is extremely slow for the battle rating.
|7.7 mm Vickers|
|Mount||Capacity (Belt)||Fire rate||Vertical||Horizontal|
Usage in battles
Exploit the A.C. IV's manoeuvrability against the heavier tanks, plus the 17-pounder tank allows for a penetration through the enemy's armour to cause internal damages. The fast reverse speed makes the "shoot-and-scoot" tactic a viable method against the enemy, and should be the prime one as the armour of the Sentinel is not exactly the most durable at only 50 mm flat. However, the sloping nature of the armour could give the bouncing capability of the tank comparable to the T-34, it's even arguably much better. So while the weight class is definitely against the Sentinel, a chance is always there to take out the opposition. When compared to other British tanks, this tank lacks access to APDS rounds. Extra caution should be paid during full uptier matches as there will be many enemy tanks, particularly German tanks, that this tank will find difficult to engage from the front.
"Shoot-and-scoot" tactics are the best tactics to use with this vehicle. The Sentinel's armour does not let the tank be a brawler, so it must be more "sneaky" against the enemies. Another thing to note is the driver's hatch at the front of the tank. To avoid a frontally penetrating shot, always angle the driver's hatch away from the enemy.
The AC.IV can play any role in the game, since it is decent at brawling, close range, mid range, and far range.
Pros and cons
- Good sloped armour
- High penetration solid shot rounds
- Good manoeuvrability
- Fast reverse speed
- Small profile
- Sloped armour only on the front
- Susceptible to large calibre HE shells
- Only 44 mm of side armour
- Cannon lacks armour-piercing rounds with high-explosive filler
- No APDS rounds, unlike other British medium tanks at this rank
- Single 7.7 mm coaxial MG with a very slow rate of fire
Australia began designing a tank in November 1940 as the AC I, and was intended to be a cruiser tank weighing between 16 to 20 tons with a 2-pounder gun. With no prior experience in producing a domestic tank, Australia sent a task force to the United States to study the M3 Medium design to understand the in-and-outs of a tank. They also received the aid of Colonel W.D. Watson MC in December 1940 from Britain, who has many years of tank designing experience. The overall mission ended up having the tank design to have a similar concept as the Canadian Ram tank, being based off the the M3 Medium chassis and mated with a domestic design of their choice for the upper part along with the incorporation of a suspension system of horizontal rubber cylinder springs seen on many early-war French tanks notably the H.39 and H.35. The Australian attached the chassis with a hull and turret with design similarities to the British Crusader tanks. The design started to become less of a cruiser tank and more of a medium tank by American specifications due to the attempt to up-armour and up-gun the tank to keep up with German armour development.
The first design was completed in February 1942 as the Cruiser Tank Mark 1 (AC I) and designated the "Sentinel". The design was simplified by using existing parts of current tanks and using a cast hull and turret. The entire hull being casted would be the first in history as many tanks of the era did not use such techniques. Although originally specified for a 2-pounder, it was then asked for a 6-pounder armament but due to the manufacturing of such guns not begining at the time in Australia they would have to use the 2 pounder for the first 65 produced. Two Vickers machine gun were used as the coaxial and hull machine gun the later having an armoured mount to protect its water sleeve resulting in a rather lewd looking front of which is made fun of to this day. With the power of three Cadillac V8 Petrol engines. It was unorthodox, but powerful enough to propel the vehicle. 65 of these tanks were made by June 1943 before being succeeded by a more advanced design known as AC III, also known as the "Thunderbolt". It had better armour and an improved firepower in the form of the 25-pounder howitzer. Despite the bigger gun, the 54-inch turret ring was never expanded to accommodate for the gun's larger size, so the crew experienced a slightly cramped turret interior for the benefit of having a better high-explosive charge and armour-piercing capability. Other differences in the design was the removal of the hull machine gun and a different set-up of the three Cadillac engines. One pilot model was built and plans were made for a production for 25 tanks for further trials, but the program was terminated.
Another attempt was made to increase Australian tank firepower with the AC IV design. It first started when the designers check to see if the turret could mount the massive 17-pounder in use by the British to fight the heavier and more protected German tanks. When the tests proved successful, the 17-pounder was chosen to be the gun for the AC IV, with a new and larger turret and 70-inch turret ring to improve crew comfort. These tanks were only made for evaluation purposes only and were never mass-produced for equipping the armoured units. However it would be the only commonwealth tank ever to mount such a gun.
The AC IV design, along with the entire Australian Cruiser tank program, was terminated in July 1943, ending with only 65 tanks produced and a few prototype models. The reason was that the funds were better spent improving the infrastructure than building new tanks due to the large number of American tanks such as the M4 Medium that were being supplied to Australia. The AC "Sentinel" were all put into storage and kept until the end of the war. The only use the Sentinel saw was in the film The Rats of Tobruk in 1943 when a squadron of AC I tanks were modified to resemble German tanks.
After the war, the Australian government disposed most of the tanks in 1945, most were sold off by the Commonwealth Disposals Commission. Today, about six Sentinels survive in intact conditions across the world. One notably in the Bovington Tank Museum, and three in Australia in the RAAC Tank Museum, Treloar Technology Centre, and one in the United States in the Collings Foundation.
Links to the articles on the War Thunder Wiki that you think will be useful for the reader, for example:
- reference to the series of the vehicles;
- links to approximate analogues of other nations and research trees.
|New South Wales Railway Company|
|Medium tanks||A.C.I · A.C.IV|
|Britain medium tanks|
|Valentine||Valentine I · Valentine IX · Valentine XI|
|Cromwell||Cromwell I · Cromwell V · Cromwell V (RP-3)|
|Cromwell derivatives||Challenger · Avenger · Comet I · Comet I "Iron Duke IV" · Charioteer Mk VII|
|Centurion||Centurion Mk 1 · Centurion Mk.2 · Centurion Mk 3 · Centurion Mk.5 AVRE · Centurion Mk 10 · Centurion Action X · FV4202|
|Vickers MBT||Vickers Mk.1 · Vickers Mk.3 · Vickers Mk.7|
|Chieftain||Chieftain Mk 3 · Chieftain Mk 5 · Chieftain Mk 10|
|Challenger 1||Challenger Mk.2 · Challenger Mk.3 · Challenger DS|
|Challenger 2||Challenger 2 · Challenger 2 (2F) · Challenger 2 TES · Black Night · Challenger 2E|
|Australia||A.C.I · A.C.IV · Centurion Mk.5/1|
|South Africa||Olifant Mk.1A · Olifant Mk.2 · TTD|
|India||Vijayanta · Bhishma TWMP|
|Israel||▄Sho't Kal Dalet|
|Sweden||▄Strv 81 (RB 52)|
|USA||Grant I · Sherman II · Sherman Firefly · Sherman IC "Trzyniec"|
|Britain premium ground vehicles|
|Light tanks||A13 Mk I (3rd R.T.R.) · A13 Mk II 1939 · AEC Mk II · Crusader "The Saint" · Rooikat 105|
|Medium tanks||A.C.I · Grant I · Cromwell V (RP-3) · Sherman IC "Trzyniec" · A.C.IV · Comet I "Iron Duke IV"|
|Centurion Mk.2 · ▄Strv 81 (RB 52) · Centurion Mk.5 AVRE · Centurion Mk.5/1 · ▄Sho't Kal Dalet · Centurion Action X|
|Vijayanta · Khalid · Challenger DS|
|Heavy tanks||Independent · Matilda Hedgehog · Excelsior · Churchill Crocodile · Black Prince|
|Tank destroyers||Alecto I · Achilles (65 Rg.) · QF 3.7 Ram|