Crusader AA Mk I

This page is about the British SPAA Crusader AA Mk I. For other variants, see Crusader (Family).

Crusader AA Mk I

AEC AA

Crusader AA Mk I

AEC AA

Britain

II Rank

Battle rating:

AB	RB	SB
3.0	3.0	3.0

Class:

SPAA

Research:7 900

Purchase:10 000

Description

The Crusader III Anti-Aircraft Mark I is a special modification of the third variant of the A15 Crusader cruiser tank family. The original 57 mm Ordnance QF 6-pounder was replaced with a 40 mm Bofors anti-aircraft gun in an open-topped turret with an autoloader and automated turret. The crew consisted of four people: the commander, the gunner, the loader, and the driver. Beginning with the Normandy landing, the Crusader III Anti-Aircraft Mark I was issued to artillery light anti-aircraft regiments, but they were withdrawn from service soon after D-Day due to Allied air superiority and a lack of Luftwaffe targets, necessitating much fewer anti-aircraft platforms.

Introduced in Update 1.55 "Royal Armour", the Crusader III Anti-Aircraft Mark I is an interesting anti-aircraft vehicle that is also capable of carrying out anti-tank roles. Despite its anti-aircraft designation, the Crusader III Anti-Aircraft Mark I struggled in this duty. The 40 mm Bofors anti-aircraft gun fires slowly with low-velocity ammunition, making it difficult to target fast-moving enemy aircraft. Nonetheless, a single hit will frequently cripple any adversary aircraft. As a result, it is critical to hide and wait for an ideal moment before opening fire on an enemy aircraft. It can also act as an anti-tank weapon. This vehicle's armour-piercing ammunition can penetrate the frontal armour of light and medium tanks, as well as the side or rear armour of some heavy tanks. Due to the low post-penetration damage, you will need to target more than one section of an enemy tank to successfully destroy it.

General info

Survivability and armour

Armourfront / side / back

Hull20 / 28 / 14

Turret30 / 12 / 12

Crew3 people

Visibility100 %

Armour type:

• Rolled homogeneous armour

Armour	Front	Sides	Rear	Roof
Hull	20 mm (33°) Front plate 9 mm (85°) Front glacis 20 mm (27°, 61°) Joint plate 20 mm (65°) Lower glacis 18 mm (1°) Driver's Port	14 + 14 mm	14 mm (14°), 12 mm (51°) Rear plate 14 mm (44-46°) Engine grille	7 mm
Turret	30 mm (36°)	12 mm (14-15°)	12 mm (19°)	N/A

Notes:

• Suspension wheels and tracks are 15 mm thick.

Mobility

Speedforward / back

AB48 / 8 km/h

RB and SB44 / 7 km/h

Number of gears4 forward

1 back

Weight19.3 t

Engine power

AB649 hp

RB and SB340 hp

Power-to-weight ratio

AB33.6 hp/t

RB and SB17.6 hp/t

Game Mode	Max Speed (km/h)		Weight (tons)	Engine power (horsepower)		Power-to-weight ratio (hp/ton)
	Forward	Reverse		Stock	Upgraded	Stock	Upgraded
Arcade	48	8	19.3	483	649	25.03	33.63
Realistic	44	7		301	340	15.6	17.62

Modifications and economy

Repair costBasic → Reference

AB520 → 669

RB386 → 496

SB602 → 774

Total cost of modifications6 940

6 730

Talisman cost530

Crew training3 000

Experts10 000

Aces115

Research Aces160 000

Reward for battleAB / RB / SB

30 / 40 / 50 %

112 / 112 / 112 %

Modifications

Mobility	Protection	Firepower
Tracks Research: 350 Cost: 340 65 Suspension Research: 310 Cost: 300 55 Brake System Research: 310 Cost: 300 55 Filters Research: 580 Cost: 560 105 Transmission Research: 750 Cost: 730 135 Engine Research: 750 Cost: 730 135	Improved Parts Research: 350 Cost: 340 65 Improved FPE Research: 310 Cost: 300 55 Crew Replenishment Research: 580 Cost: 560 105	40mm_usa_M2_HE_ammo_pack Research: 350 Cost: 340 65 Horizontal Drive Research: 350 Cost: 340 65 40mm_usa_M2_AP_ammo_pack Research: 310 Cost: 300 55 Adjustment of Fire Research: 310 Cost: 300 55 Elevation Mechanism Research: 580 Cost: 560 105 Artillery Support Research: 750 Cost: 730 135

Armaments

Main armament

40 mm Bofors L/60 cannon

Ammunition160 rounds

Belt capacity8 rounds

Reloadbasic crew → aces

0.6 → 0.5 s

Fire rate120 shots/min

Vertical guidance-6° / 70°

40 mm Bofors L/60						Turret rotation speed (°/s)					Reloading rate (seconds)
Mode	Capacity (Belt)	Fire rate	Vertical	Horizontal	Stabilizer	Stock	Upgraded	Full	Expert	Aced	Stock	Full	Expert	Aced
Arcade	160 (8)	120	-6°/+70°	±180°	N/A	35.22	48.75	59.20	65.47	69.65	0.65	0.57	0.53	0.50
Realistic						23.80	28.00	34.00	37.60	40.00

Ammunition

• Default: AP-T · FI-T* - These work fine, a hit on an aircraft means certain death for it and still is able to hurt ground vehicles, especially if it is side into the side of a enemy tank. These seem like a good I don't know what i will run into belt.
• Mk.II: FI-T* - These mean certain death for aircraft, what should be used for AA work.
• M81A1: AP-T - These are the worst belts against airplanes. however, they are able to hurt ground vehicles especially if it is side into the side of a enemy tank. If you plan on killing tanks load this and flank, since side shots are almost a necessity.

Penetration statistics
Ammunition	Type of warhead	Penetration @ 0° Angle of Attack (mm)
		10 m	100 m	500 m	1,000 m	1,500 m	2,000 m
Mk.II	FI-T*	9	8	7	6	5	4
M81A1	AP-T	72	69	58	46	37	29

Shell details
Ammunition	Type of warhead	Velocity (m/s)	Projectile mass (kg)	Fuse delay (m)	Fuse sensitivity (mm)	Explosive mass (TNT equivalent) (g)	Ricochet
							0%	50%	100%
Mk.II	FI-T*	874	0.83	0.1	0.1	63	79°	80°	81°
M81A1	AP-T	875	0.88	-	-	-	47°	60°	65°

Ammo racks

Ammo racks of the Crusader AA Mk I

Full ammo	Ammo type	1st rack empty	2nd rack empty	3rd rack empty	4th rack empty	5th rack empty	Visual discrepancy
20 160	Clips Rounds	15 (+5) 120 (+40)	10 (+10) 80 (+80)	5 (+15) 40 (+120)	1 (+19) 8 (+152)	0 (+20) 0 (+160)	Yes

Notes:

• Ammunition is organised in clips of 8 rounds.
• The visual discrepancy concerns racks and clips: racks 1 to 4 are modeled as 9 clips containing 4 rounds while rack 5 is a clip of 4 rounds. In-game, racks 1 to 4 contain 5 clips of 8 rounds and rack 5 contains a clip of 8 rounds.
• Racks disappear after you've fired all shells in the rack.

Usage in battles

Despite being an SPAA vehicle, the Crusader struggles in an AA role. The gun is slow firing and fires at quite a low velocity, meaning that you will struggle to target fast moving enemy aircraft. Granted, a single hit will often spell doom for an enemy aircraft. Therefore, it is important to hide and wait for an opportune moment to open fire on an enemy aircraft. A low flying aircraft within 1km, flying at low speed, should be easier to hit. However, higher ranked and faster planes will can be a much harder target to his with the slow turret traverse for tracking and the slow fire rate of the gun.

The Crusader AA Mk I can also serve in an anti tank role. With armour piercing rounds, the Crusader performs better than most SPAA in this role. With 76 mm of penetration, you can penetrate the frontal armour of light and some medium tanks and the side or rear armour of some heavy tanks. Poor post penetration damage means that you will need to target various sections of an enemy tank in order to destroy it. Some tanks will be almost invulnerable to your rounds, and while tanks KV-1 ZiS-5 can be dealt at point-blank range on the side or rear, there are many other heavy tanks that the 40 mm cannon will not penetrate.

Pros and cons

Pros:

• Good mobility and top speed of the Crusader chassis
• 40 mm Bofors autocannon can heavily damage aircraft if the Mk.II shell contacts
• Tall turret offers good protection to the gunnery crew from machine guns up to 20 mm cannons
• AP shells have enough power to penetrate some tank armour

Cons:

• Very little armour, especially the AA turret
• Cannon slot in front turret armour allows machine gun bullets to go through and injure/kill the crew
• Against attacker and bombers, 40 mm cannon is not a one-hit kill and repeated hits are necessary
• Exposed top leave crew vulnerable
• Slow rate of fire and muzzle velocity
• Limited ammo, which could be a problem since the gun requires leading of shots

History

Development

In 1938, the General Staff of the British Army requested for a cruiser tank that was lighter and more affordable than the heavier A16 cruiser design developed by Nuffield Mechanizations & Aero. One of these designs was the designation Tank, Cruiser Mk.V based off the A13 cruiser tanks, named the "Covenanter", and Nuffield was invited to become part of its development team, but they refused due to interest in developing their own cruiser tank. Their tank was designated the Tank, Cruiser Mk.VI Crusader and fell under the General Staff specification of A15. The Crusader was a parallel design to the Covenanter, but was ready six weeks earlier than the Covenanter despite starting at a later time. The Crusader was adopted into service with the British Army in 1941 and the 5,300 units were manufactured between 1940 to 1943.

Design

The Crusader features a new design that differs from its cruiser tank predecessors. The Christie suspension system on the Crusader had five road wheels for it instead of the usual four, which improves weight distribution of the increased 20 ton weight of the Crusader compared to the 14 tons of the A13 cruisers. The engine, steering system, and cooling system on the Crusader was different as well, but the Covenanter and Crusader use the same main turret. The polygonal shape of the turret gives the crew inside more room for the turret ring diameter.

The Crusader Mk I and Mk II were equipped with the 2-pounder, which was aimed by the gunner inside with a padded shaft that allows them to elevate the gun by simply adjusting his own height. Later in the war where an up-gun of the tank armament was necessary and newer tanks such as the Cromwell was delayed, the Crusader was upgraded into the Crusader Mk III variant with a 6-pounder instead, which restricted turret space, requiring the turret crew to be reduced from three to two. These saw first action the Second Battle of El Alamein in October 1942.

Combat usage

The Crusader first saw action at North Africa, right after the British had been pushed back to the Egyptian border by Axis forces. The Crusaders were part of the huge shipment in the Malta Convoys to reequip the British forces there. Enough Crusaders arrive that the entire 6th Royal Tank Regiment was refitted with them, which joined up with the 2nd Royal Tank Regiment to form the 7th Armoured Brigade "Desert Rats". The brigade's first action was in Operation Battleaxe, though it was delayed due to adapting the tanks for the desert environment. The operation, which called for the relieve of the siege of Tobruk in June, was initiated in June to which 11 Crusader tanks were lost to anti-tank guns, plus many more to mechanical faults. While more Crusader tanks came in to reinforce the cruiser tank forces, there were never enough to supply the continuously expanding armoured units as 7th Brigade was combine with the 7th Hussars, the 2nd Armoured Brigade was added to the 7th Armoured Division, and the 8th Hussars was combined with the 4th Armoured Brigade. Overall, the Crusaders proved effective in the North African Campaign, the Crusader was faster than any tanks on the opposing side and the 2-pounder was lethal to the Panzer III, but the tank suffered from its thin armour, mechanical problems in the desert, and the growing deficiency of the 2-pounder, which didn't have enough range to destroy farther tanks. The Crusader design also caused the ammo racks on the tank to easily ignite due to unprotected racks and shot traps on the turret design. Anti-tank guns continue to be the main reason the Crusader units suffer losses, rather than to enemy tanks.

By the end of 1941, only the 2nd Armoured Brigade retained the Crusaders, the rest of the other tank units were being refitted with better tanks, such as the M3 Grant medium tank from the American Lend-Lease. Crusader units were also refitted with the more powerful Crusader Mk III with the 6-pounder, which improved the Crusader's ability to destroy the gradually stronger German tanks. After General Bernard Montgomery took command of the British Army in 1942, more British tank units were reequipped with the Grant and M4 Sherman tanks while the Crusaders were relegated from the front-lines to "light squadrons" meant to flank the enemy and attacked at its exposed sides. When the British 1st Army engaged the Axis at Tunisia, some tank regiments still use Crusaders mixed in with Valentine tanks. These units in the 26th Armoured Brigade, code named "Blade Force", worked alongside the 78th Infantry Division as an independent armoured column. During Tunisia, the 1st Army was already converting the tank regiments into Shermans, but the 8th Army continued to use the Crusaders for much longer, which would see use at the Battle of Wadi Akarit and Mareth Line.

After the North African Campaign, the Crusaders no longer saw any use in the front-lines and were used in other roles such as gun tractors with 17-pounders or anti-aircraft mounts such as the Crusader AA Mk I and Mk II Some Crusader tanks equipped the tank regiments that stayed back at the British Homelands such as the 11th Armoured Division.

The AA Tank Mk 1 was issued to artillery light anti-aircraft regiments starting with the landing in Normandy, but the Mark I's were withdrawn from service soon after D-Day due to the Allied air supremacy and lack of Luftwaffe targets meaning significantly fewer anti-aircraft weapons ended up being required.

Survivors

About 21 Crusaders still exist intact in various parts of the world. The most notable places with the Crusaders are South Africa with 8 known survivors, a running Crusader Mk III at Bovington Tank Museum at England, and an anti-aircraft version at Musée des Blindés in France.

Media

Skins

• Skins and camouflages for the Crusader AA Mk I from live.warthunder.com.

Images

• 

  Crusader AA Mk I in Normandy map

See also

• Ostwind
• ZSU-37
• AMX-13 DCA 40
• Lvkv 42

External links

• [Devblog] Crusader AA Mk.I and Crusader AA Mk.II
• [Tanks-Encyclopedia] Cruiser Mk.VI Crusader (Web Archive)

Nuffield Mechanizations and Aero Limited
Cruiser Tanks
Tank, Cruiser, Mk III (A13 Mk I)	A13 Mk I · A13 Mk I (3rd R.T.R.)
Tank, Cruiser, Mk IV (A13 Mk II)	A13 Mk II · A13 Mk II 1939
Tank, Cruiser, Mk VI, Crusader (A15)	Crusader II · Crusader "The Saint" · Crusader III
Tank Destroyers	Tortoise
SPAAs	Crusader AA Mk I · Crusader AA Mk II
Export	▄Crusader Mk.II

Britain anti-aircraft vehicles
Crusader AA	Crusader AA Mk I · Crusader AA Mk II
Wheeled	Staghound AA · AEC AA
Radar SPAAG	Chieftain Marksman
Missile SPAA	Stormer AD · Stormer HVM
Other	Light AA Mk I · Falcon
Canada	Skink · ADATS (M113)
South Africa	Ystervark · Bosvark · ZA-35