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Pic 1: Crusader AA Mark III T127084 ‘ALLAHKEEFA’ of 22nd Armoured Brigade HQ, 7th Armoured Division coming ashore on in Normandy on 7th June 1944. Note the front mounted aerials of the AA Mark III, the exhaust trunking and waterproofing on the air cleaners and mantlet front. (IWM 5129) Having been on the receiving end of efficient close support air attacks from the Luftwaffe in France in 1940 and later in the North Africa campaigns, the British army looked into antiaircraft protection for armoured vehicles. At one level each vehicle having a Bren light machine gun on a suitable mount could provide it, but that lacked both range and firepower.

The first proper AA armoured vehicles were built on Light Tank Mark VI series tanks and Humber armoured cars. These consisted of an open-topped turret fitted with four 7.92mm BESA machine guns. These did give a fairly high rate of fire, but range and effectiveness was still not great.

The answer came in the form of the 20mm Oerlikon gun. Widely used - my late father manned one at the time of the D Day landings serving as part of the Royal Navy’s Defensively Equipped Merchant Ships branch or DEMS - some class this as a ‘cannon’, but contemporary sources describe it as a machine gun.

The official ‘Royal Armoured Corps Weapons, Military Training Pamphlet No.35 Part 5’ of September 1943 gives its designation as 20mm Oerlikon Machine Gun. This gives basic data on the gun, telling us it was eight feet long, weighed 141 lbs, was 20mm or 0.787in calibre, fired shells with a muzzle velocity of 2,725 feet per second at a rate of 450 to 480 rounds per minute giving it an effective range of up to 1,200 yards against aircraft.

Several types of ammunition were available including British-made HE, HE Incendiary and Practice all with and without tracer as well as HE and HE Tracer of American manufacture. ‘Live’ ammunition was fitted with a contact fuse and the tracer burned for 3.75 seconds. Rounds weighed 8.5ozs each and were fed from 60 round magazines; these were spring-operated and weighed in at 63 pounds fully loaded of which just under half was the magazine itself.

This weapon was adapted for vehicle use on a Crusader tank hull. Two slightly different versions were produced, similar enough to both be covered in the same Instruction Book, Chilwell Catalogue No 62/451 from March 1944 for Crusader III, A.A. II and III. This describes the vehicles -

‘The Crusader III, A.A.II & A.A.III have both been designed and built for defence against low flying aircraft and, due to the high power to weight ratio, the acceleration and general performance is of a high order. These facts combined with the firepower of the twin Oerlikon machine guns; place an important weapon in the hands of the crew.

The difference between the two vehicles is mainly in the turret, and in the case of the Crusader III, A.A.II the W/T set is fitted in the rear of the turret, but in the A.A.III this space is utilised by the commander/gunner, thus providing more room in the fighting compartment. The W/T set in this case is fitted in the left-hand forward compartment.’

All the differences are noted. Under Crew, the Instruction Book tells us that the AA.II had a four-man complement of Commander/Gunner, two loaders and a driver, though on the A.A.III the driver operates the W/T set. On both types, the turret is a welded structure, with the exception of the front plate, which is bolted in place.

Suspended from the turret by tubular supports is the turntable on which is carried the commander/gunner’s and loader’s seats. The whole turret assembly is carried on a caged hull race and rotated through 360º by means of a hydraulic traversing gear, or manually by gear engagement on a fixed rack-ring.

Twin Oerlikon guns are fitted and high angle elevation is provided by a special rotating mantlet pivoting on trunnion bearings formed by ‘hanger brackets’ suspended from the turret roof. A handlebar type of hydraulic valve box, the head of which moves in two directions, controls the operation of traversing, gun elevation and depression. The rotary movement of the valve box head controls the turret traverse, while the movement from the vertical controls the gun elevation, etc.

The ring sight is mounted in an inverted ‘U’ shaped bar, pivoted at either end to the turret side plates, and connected to the gun cradle by means of a link bar, so that the sights alter in correct relationship to the gun elevation or depression.

On Crusader III A.A.II a hinged cover of armour plate affords protection in action by reducing the sighting aperture to a minimum. This cover is operated by a lever inside the turret, and secured in the upright position by a spring-loaded catch. The turret roof is open, but a folding hinged metal cover is provided as a waterproof covering, arranged so that it can be drawn over the roof, folding against the turret rear sloping plate when out of use. Two periscopes are fitted to provide vision facilities for the loaders.

On Crusader III A.A.III the turret differs from the Crusader III A.A.II, the rear plate having been extended to permit the commander/gunner to sit further back, this providing a greater range of view and allowing more room in the fighting compartment. An armoured shield is provided for additional protection for the commander/gunner.

Additional details are provided in the Illustrated Parts List for the A.A.III that also covers the Mark III gun tank and Gun Tractor variants.

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Pic 2: Illustration of the 20mm Oerlikon Mark II cannon with a breakdown of parts from Royal Armoured Corps Weapons, Military Training Pamphlet No.35. Part 5: 20-mm Oerlikon Machine-Gun 1943. Contemporary Army documents describe this weapon as a machine gun.

Guns were carried in a ‘Mounting, Twin A.A. Oerlikon 20-mm M.G. Mark I’. Some books state that there was also a coaxial .303in Vickers K or Gas Operated machine gun on the AA.III as well, but the Vehicle Instruction Book does not list it and nor does the Illustrated Parts List. That shows a counterweight on the outside of the mantlet consisting of a large metal cylinder mounted on a threaded rod with large nuts at either end of the cylinder to allow for adjustment back and forth. This mounting allowed for almost vertical fire of 87º elevation along with 5º depression.

Tracing the development is not easy as sources can conflict with each other; ‘Appendix K’ to the Half Yearly Reports on the Progress of the Royal Armoured Corps for January-June 1942 says:

(6). Twin Oerlikon on Crusader. This mounting which it is hoped will soon be ready for trial is a twin 20 mm. Oerlikon mounted on a Crusader. Requirement 400. Production forecast - Commence in September 1942, 146 by end of January 1943. These will be issued to armoured regiments, Tank Battalions, and Divisional H.Q. on the scale mentioned in (1) above.

This scale was to be two per Divisional H.Q. and eight in each Armoured Regiment and Tank Battalion. A Contract Card exists in the Tank Museum’s Archives for contract 294/8M/3432 dated 26th October 1942 to ‘Convert 200 Crusaders fitted with 2pdr & BESA Mountings to Crusader A.A.II type with Dual Oerlikon Mountings’ which shows plans to rebuild existing Crusader II gun tanks to this standard. This seems not to have happened, though trials of the new system took place and the reports on these can be followed.

Report FT843 ‘Interim Field Trials Report on Traverse Gear, Twin Oerlikon - Crusader’ from late June 1943 records that pilot machine T45040 (a Crusader II built by Nuffield) was sent to the Fighting Vehicles Proving Establishment by Nuffield subsidiary Morris Industries Exports Ltd and later handed over to the V/EL Laboratory for special tests. The vehicle had frequent engine defects and was withdrawn from trials after it had done 291 miles on the road and another 125 cross-country. The turret was out of balance as the rear face was ‘considerably thicker’ than specified for production machines, and 245lbs had to be added to the front turret plate to correct this problem. Traversing stop for the power traverse spade grip was found to be sheared, a new one was made by Messrs Powered Mountings and the design was to be strengthened.

There was excessive over-run when traversing onto a target. The guns could not be elevated or depressed while the turret was traversing at full speed, as there was not enough power in the hydraulic system. Also, when the guns were fully elevated, a flexible pipe to the firing mechanism was crushed by one of the magazines. This vehicle was fitted with a coaxial Vickers between the main guns, though there was not enough space for its spent cartridge bag and so spent cases could jam the Oerlikons. Loaders’ positions were cramped and it was thought their legs could be injured during traversing. The report ended, ‘It is suggested that numerous modifications will be necessary before the Twin Oerlikon Crusader can be considered an efficient AA weapon’.

Report FT843/1 on trials run a couple of weeks later was a test of performance and reliability of traverse and turret construction, this time on an unidentified production machine from Morris Industries Exports Ltd. Cocking and firing mechanisms were not fitted when it arrived, so these were taken from the pilot machine. Battle weight was 19 tons 13 cwt, the vehicle clocked up 509 road miles and the same distance cross country in exceptionally dusting conditions at Long Valley, Aldershot and on the Chobham cross country course. The same slow elevation and depression and overrun in traverse were still a problem, but the pipe damaged in the earlier trial was now re-routed. Turret structure, gun mounting and general layout were thought sound, but loader’s positions were extremely cramped and more modifications to the traverse gear were needed.

The other trials mentioned led to V/EL Report No 32 ‘AA Protection for AFVs - Crusader with Twin Oerlikon Mounting - Performance Characteristics of Traversing and Gun Elevating Gear’ dated 19th July 1943. This states that the Oerlikon Crusader Mark II had been released for production and a 1,000 miles reliability trial and tests for general suitability was carried out on tank T125607 (See photo). It describes the equipment and tells us that a special controller of ‘handlebar type’ was used to traverse the 3.1-ton turret using a hydraulic system and also elevate the guns via a hydraulic ram.

Trials with a camera gun in late May and early June against a Hurricane flying at around 300mph at Lulworth showed that the system could not track targets passing across the line of the guns in both vertical and horizontal planes at the same time.

As extensive trials against real aircraft were not practicable, a car was used suitably placed to mimic the actions of a plane at a greater distance in early July. Results showed good controlled traverse speeds of around 10º per second, though at speeds above 40º per second it tended to move too quickly and point the guns ahead of the target at higher speeds mainly due to it not being able to slow down fast enough. Also the pump could not allow smooth and fast operation of both traverse and elevation at the same time. Operating speed depended on engine speed as the hydraulic pump was powered by the main engine.

V/EL Report No 50 covered Camera Gun Trials against a Jeep fitted with a cylindrical object 19in by 16in as a target on Cobham Common in late August. This was for tracking only as the target could not move up and down. The Jeep was driven at around 24mph across the gun’s path at distances of 20 and 40 yards, equivalent to a plane flying at 240mph at 200 and 400 yards respectively which it was said, ‘represents a very difficult target for tracking compared to an approaching target’ as the rate of movement which had to be followed was greater.

Several different gunners with varied amounts of experiences tracked the target. In general, they all performed well until the target was at 45º from the vehicle, then as traverse had to speed up to follow the vehicle they tended to aim ahead, lose the target and have to hunt for it. When it reached 60º away on the opposite side they were able to track it smoothly again. The conclusion was that few hits would have been scored had the guns fired as the best aim was at a time when the target was beyond the effective range of the guns.

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Pic 3: Late-manufactured Crusader (T125607) converted into an AA Mark II and the particular vehicle that a 1,000 miles reliability trial and tests for general suitability were carried out on. Note the radio aerials on the turret rear, which is where the radio was located in the Mark II. (Crown Copyright)

V/EL Report No.70 covered tests against a projected spot of light on a screen using new gear ratios and seating arrangements on the old T16614 in September 1943 and the more up-to-date T125605 in February 1944. It was found that used equipment produced less violent response to the controller, which made tracking easier. The controller handles tended to jam and could not be adjusted for height though the operator’s seat was adjustable.

In March 1944 tests were carried out on an older version tank T45040 with a more powerful pump, but while there were some improvements the tank was in a poor mechanical state which meant it could not perform as well as it might have. More trials covered different sights and an alternative pump design with higher capacity. These used T16614 again, but as the vehicle was worn out the equipment was moved to T125605. This produced better results, but was found to need more cooling than the existing design.

The main conclusions were that the handlebar-type controller was the best then available, it had to be light and consistent in operation and the operator should be comfortable.

Acceptance trails noted that ‘deleting the Vickers ‘K’ and adding an external balance weight greatly improved the mounting’, which would explain why it was not fitted on production vehicles. All the trials appear to have been on A.A.II standard vehicles, as far as I can tell none used the A.A.III though tank T16614 - an old vehicle, this was a Mark I built late in 1941 - was used as the illustrative photo in the March 1944 Instruction Book, and T125605 was apparently converted to an AA.III in June 1944

Production and Service

Towards the end of Crusader tank production, tanks were built without turrets and stored for use as special purpose vehicles. Figures recorded in Cabinet Office papers show that for the first months of 1943 between 50 and 65 complete tanks were built each week, but in mid-late June a small batch of Observation Post tanks was built while the final 210 vehicles from late June to the start October were hulls only with production falling week by week.

Some were converted to A.A.II standard, but records are hard to track down and few photos seem to have been taken of either type, which various reports are sometimes vague as to the sub-types.

In the Half Yearly Report on the Progress of the Royal Armoured Corps for 31st December 1943, Crusader AA were listed in service - Crusader A.A. Mark I - 2 in Training Units, 3 in Establishments, 205 in Ordnance Depots. Crusader A.A. Mark II - 4 in Guards Armoured Division, 25 in Training Units, 44 in Establishments, 90 in Ordnance Depots.

However, the Mark I was a different vehicle altogether. Mounting a single 40mm Bofors it was used by Royal Artillery units and should not figure in RAC records.

More details emerge in the section on vehicle developments and production, Appendix Y. This recorded the fact that the early vehicles had turrets that were seriously out of balance, and stated:

‘100 out of the 400 vehicles will be issued for training purposes only. At present they are unmodified and training units have been warned of the cramped position of the loaders; their legs are liable to be badly damaged when the gun is in extreme elevation. Modifications will be introduced retrospectively whereby the loaders seat will be lowered by 4.5in to give more clearance. The remaining 300 vehicles will be issued to Armoured Regts, Tank Bns and Div HQ on the scale -

Each Divisional HQ - 2

Each Armoured Regiment, and Tank Battalion - 6

Each Brigade HQ - 2

Each Armd Recce Regt - 5’

Why an Armoured Reconnaissance Regiment only needed five vehicles while other units warranted six is not explained.

According to files at the National Archives, the original production forecast for AA tanks for 1944 was 65 in January, 75 in February, 100 in March and 60 in April to make a grand total of 300 against the 1944 Requirement. However, as at 19th July 1944 only 268 had been converted. A report stated that Oxford-based Nuffield subsidiary Morris Industries Exports Ltd., were working on ‘Crusader Oerlikon Reworks’ from September 1943 and West’s Gas Improvements Ltd., in Manchester also transferred to work on them in February 1944 though it does not say how many were to be completed by each.

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Pic 4: The cramped turret interior of the Crusader AA with the guns at full elevation viewed from the gunner’s seat. (1) Left 20mm gun loader’s seat. (2) Breech of left 20mm Oerlikon gun. (3) Left 20mm 60-round magazine. (4) Breech of the co-axial Vickers .303in ‘K’ gas operated machine gun mounted between the 20mm guns. (5) Breech of the right 20mm Oerlikon gun. (6) Right 20mm gun loader’s seat. (7) Gunner’s hydraulic traverse, elevation, depression and gun firing control.

This would agree with figures from the Half Yearly Reports on the Progress of the Royal Armoured Corps of 299 vehicles being built. In June 1944 they state that 300 Crusader III AA Mark II had been ordered, production figures were not listed, but it was ‘in service’. A detailed listing for 21st Army Group AFVs showed a total of 252 in service with units; see Table One.

This listing, while dated 30th June, looks more like what would be expected before the D Day landings and probably reflects the situation in late May or early June. As can be seen, some units were still not up to full strength and the 1st Polish Armoured Division had yet to receive any, though several photos show them in Polish service in Normandy, with many appearing in a recent Polish book on SP guns.

The Report also now lists the AAII, which was described as unbattleworthy, it had the coaxial Vickers ‘K’, but that was to be disregarded in training. Production was limited to 100 and all had been built. The December 1944 report only includes the Crusader III AAIII, stating that 299 had been ordered and these had all been built. But that is getting ahead of the story.

Units were getting the new vehicles and training to use them; 8th Armoured Brigade collected nine Crusader AA from Cowley, Oxford on 22nd February. The AFV State for 7th March shows one at Brigade HQ, two in 4th/7th Dragoon Guards and three each with 24th Lancers and Nottinghamshire Sherwood Rangers Yeomanry.

Courses were run in March including range firing with Brigade HQ allocated 300 rounds and each Regiment 400 rounds each. By 20th March each Regiment had five vehicles with none in Brigade HQ; a week later the Brigade was up to full War Establishment apart from being one vehicle short in 4/7DG, and by 3rd April they were at full strength. According to their landing plans, the AA tanks in the Regiments would not be landed until D+5 and those of Brigade HQ until three weeks after D Day. While there are regular records of tank strengths, there are no mentions of AA vehicles.

The 13th/18th Hussars War Diary tells us they underwent a general reorganization on 10th July with new tanks, three in Squadron HQ and four troops each of four tanks with 17pdr Shermans spread equally between all Squadrons but no mention of AA tanks until 17th August when it was recorded that ‘AA Tp is being done away with’.

The 22nd Armoured Brigade’s War Diary does not have much on the build up of AA tanks, it does record on 15th March 1944 - ‘It was stated that the Bde may have to accept its full quota of AA tanks, the balance not already including in the loading tables may therefore have to proceed overseas with the residue’. This refers to the landing of vehicles in France, and suggests that not all vehicles would land in the first wave. However, when they landed on D+1 the Diary says that 130 Cromwell 75mm, 15 Cromwell CS, 15 Sherman VC and 31 Stuarts were ashore successfully without mentioning the AA tanks, but under ‘Tks temporarily drowned’ were:

Bde HQ - 1 Cromwell IV, 1 AA Tk.

5RTR - 1 Sherman VC, 1 Stuart.

4 Sharpshooters - 1 Sherman VC, 1 Stuart, 1 AA Tk.

Presumably all the other AA Tanks including 22nd Brigade HQ’s ALLAHKEEFA and 1RTR’s SKYRAKER, which were both photographed, got ashore as intended.

The 1RTR War Diary tells us that training on AA tanks began in late February. On 1st April they had three Crusader AA, though on the 7th this fell to two and remained so until the end of the month. Further figures do not appear to have survived, but a detailed breakdown of their own and attached vehicles for 21st May shows they had six. There is a detailed list of tank serial numbers, names, call signs and commanders for that period, but the AA tanks are not included and indeed Regimental HQ details appear to be missing.

For the 7th June when they landed in France, the Diary states: ‘From 1400-1600hrs the tanks of the Regiment were disembarked. This operation was completely successful. The tanks went to SOMMERVIEU 825808, where they leaguered and carried out de-waterproofing. The Unit leaguered at this place for the night.’ The photo of SKYRAKER was presumably taken during the move to Sommervieu.

Again the AA tanks were not mentioned, the tank strength figures for July cover Cromwells with CS tanks listed separately, Firefly and Stuarts only, while those for later months give just a total figure.

Some details appear in other War Diaries. 2nd (Armoured) Battalion Irish Guards state that they were: ‘still short of 9 Sherman ‘Fireflies’, 2 Sherman ARVs and 3 A/A Crusaders’ on 28th May, though a list of vehicles for the end of the month showed six Crusaders with names and service numbers of the crews, but unlike their other vehicles did not record their serial numbers.

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Pic 5: One of the reasons the right hand 20mm cannon barrel protrudes further is that when the guns had to be turned in their mounting so that the 60-round magazines would be positioned in front of their specific loaders, the horizontal handgrips prevented this ... So the right hand gun was moved forward slightly to overcome this as illustrated here. (A) Left 20mm gun. (B) Right 20mm gun. (C) Breech of the Vickers .303in ‘K’ gas operated machine gun, which was deleted on production models and an external cylindrical counterweight added to the front of the mantlet to balance the mounting from its omission. The Oerlikon guns were cocked by ratchets rather than lanyards when mounted in the Crusader’s AA turret.

All the effort which went into designing, testing and building these vehicles, training crews, issuing them and taking them to France seems to have had little result. So far, no account of them bringing down any aircraft has come to light, and the AA Troops were disbanded in July/August. This is confirmed and the fate of some vehicles is given in ‘21 Army Group RAC Liaison Letter No 2’ of September 1944. It reads: SECTION D - AFV AA EQUIPMENT 26. AA TANKS (a) Air superiority is such that AA tks have been dispensed with. (b) A number of the AA tks thus rendered surplus have been issued to certain CO’s and Bty and tp comds of A-Tk Regts as chargers on the following maximum scale: (i) One for C.O. of Corps and Armd Div Regts. (ii) One for SP bty comd in Corps or Armd Div Regts. (iii) One for each SP tp comd in Corps and Armd Div Regts.

I take it that most readers will know ‘tks’ is short for tanks and what the abbreviations for Commanding Officer and other Commanders, Self-Propelled, Battery, Troop and Armoured Division are. ‘Chargers’ sounds like a throwback to the days of horse-drawn artillery, but at least Crusaders would be faster in that role that the Valentines some units had.

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Pic 6: Crusader AA Mark III ‘SKYRAKER’ (also named ‘The Princess’) with the markings for 5 RTR, 22nd Armoured Brigade, 7th Armoured Division in Normandy 7th June 1944. This is the subject vehicle of Jay Laverty’s model elsewhere on the site. (IWM B5124)

Redistribution

Some idea of the date of this change comes from the War Diary of 256 Army Delivery Squadron RAC. Their own account of the NW Europe campaign made special mention of their work in withdrawing these vehicles. Some units were still receiving their allocation in July.

The 256ADS Diary says they received 15 from 257 Corps Delivery Squadron on the 11th and 12th of July, and issued five or six - the original record was typed and the figure was overtyped - to 91 Antitank Regiment (a Corps level unit in VIII Corps) and one to 2nd (Armoured) Battalion Irish Guards in Guards Armoured Division on the 13th. Eleven more came in from 263 Forward Delivery Squadron on the 22nd, while on the 24th and 25th a total of seven were sent to 6th Guards Tank Brigade. However, on the 26th, four were received from 141RAC - a Churchill Crocodile unit - and on the 30th five more from 31st Tank Brigade.

Later entries only give overall totals, but a series of reports of AFV and RA Equipment State recorded on 21 Army Group Form 42 and marked TOP SECRET show more detail. They recorded the number of vehicles with the various Delivery Squadrons, for 256ADS the number of vehicles rises from four on 2nd August to 34 on the 4th and 52 on the 10th, which suggests that most withdrawals were carried out at the start of August. 257CDS also held 10 at this period, and most vehicles were classed as ‘unfit’. Numbers fell in these two units, but the other British and Canadian Delivery Squadrons had smaller numbers. By the end of August the overall total number they held between them was 31, dropping to 15 at the end of September and down to 9 at the end of October, with none in the Canadian squadrons.

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Pic 7: Crusader AA Mark III ‘CHAOS’ of the Staffordshire Yeomanry, 27th Armoured Brigade at the beginning of Operation Goodwood, 18th July 1944. The Brigade’s familiar Seahorse badge is clearly visible on the front of the left stowage bin and the unit’s serial number (52) on the aerial bracket. (IWM 7522)

While most units handed over all or at least most of their vehicles, one regiment not only kept them, but also increased their stocks. The South Alberta Regiment, who were the Sherman-equipped Armoured Reconnaissance Regiment of 4th Canadian Armoured Division, acquired one extra vehicle to their original six - they appear to have operated on the War Establishment of an Armoured Regiment and not an Armoured

Reconnaissance Regiment - to give them seven in all. This may have come from the Polish 10th Mounted Rifles, who were Recce for 1st Polish Armoured Division. A short sequence of film, now in the Pathe Gazette, shows their AA tanks fitted with extra .30in Browning machine guns on the turret, passing the cameraman near Xanten in February 1945. The serial of one tank can be read, which is the same as on a photo which credits its owner as the Polish unit. The film and photos in the regimental history show a large square stowage box fitted onto the turret rear.

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Pic 8: An AA Mark II turret fitted to what is most probably an old Mark I tank going by the earliest form of felt element air cleaners and its very worn down tracks! Although no serial number is visible this is most likely one of the old Mark I vehicles used for trials. (Crown Copyright)

The December 1944 tank strength summary in the RAC Half Yearly reports shows that some armoured units kept their AA tanks while others did not; see Table 2. The Czech Armoured Brigade may never have been issued with any vehicles, and the independent Armoured Brigades seem to have given their vehicles up. By chance however, photos exist of the 8th Armoured Brigade’s single vehicle. A photo was taken by Stuart Hills of Nottinghamshire Sherwood Rangers Yeomanry that appears in his own book ‘By Tank Into Normandy’ and also in Patrick Delaforce’s book on 4th and 8th Armoured Brigades. Another photo was taken by Sergeant Christie, No 5 Army Film & Photographic Unit at Issum, Germany on 6th March 1945 and the photo is in the Imperial War Museum’s files as B15234. Both photos show a large amount of equipment stowed on the engine deck, covered in a tarpaulin.

By June 1945 none were listed in service in the RAC Half Yearly Report. Production details state:

(a) Crusader III A.A. III - All Crusader III A.A. III weighing 19.25 tons, mounting the Twin 20mm Oerlikon Guns, issued to 21 Army Group for operations in N.W. Europe have now been withdrawn.

An order to make a census of AFV stocks in NW Europe dated 18th July 1945 listed several types of tank that were to be counted, including three types of ‘Valentine Charger’ with 2pdr, 6pdr and 75mm guns, but did not mention Crusader AA.

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Pic 9: Crusader III AA Mark III. Note the wading trunk stowed against the back of the near vertical, extended rear face of the turret and the spare wheel. Vehicle is marked with the diamond of an HQ unit. This low angle shot also reveals the flat ‘fishtail’ type exhaust outlet exiting centrally below the bottom slat on the engine compartment louvres. L&AC PA193591.

End Note

For all the effort involved, the Crusader AA tanks appear to have made little impact on the battlefield. I have found no record of them firing in anger let alone details of any planes they may have brought down.

Their planned replacement with the Polsten-equipped Centaur AA proved to be unnecessary and apart from the few vehicles kept by a few units, they were discarded within weeks of going into action. Secondary use with artillery units was more making use of what was available than anything else.

Flying Bomb Practice

One unusual if short-lived role for them was the allocation of six sited near Hastings in early July 1944 to counter flying bombs. A report stated that their actions were restricted; they could only fire out to sea as their 20mm ammunition did not have self-destruct fuses and this rendered them of little operational value. Each of the tanks was located close to a 40mm Bofors gun and a single Polsten. In all, only 16 engagements had taken place.

Their crews felt that they could track the V1s that flew by, their reckoning at speeds between 200 and 400mph at between 1,000 and 6,000 feet. Target engagement was usually three or four seconds which meant they did not need to reload. Tracer ammunition was used to aid aiming, and firing was at ranges of from 1,800 down to 1,000 yards. For some reason different sights were fitted, one was a 300-knot cartwheel and the others had 200-knot sights. Oil seals on the valve boxes leaked and one gun spring was reported broken. The report concluded that they would be best located in groups of three with a 180º arc of fire.

References

National Archives, Kew -

WO 165/132 R.A.C. Progress Report: No. 6 July - December 1942

WO 165/133 R.A.C. Progress Report: No. 7 January - June 1943

WO 165/134 R.A.C. Progress Report: No. 8 July - December 1943

WO 165/135 R.A.C. Progress Report: No. 9 January - June 1944

WO 165/136 R.A.C. Progress Report: No.10 July - December 1944

WO 165/137 R.A.C. Progress Report: No.11 January - June 1945

WO.171/153 War Diary for RAC Branch, Main HQ, 21st Army Group 1944

WO.171/619 22nd Armoured Brigade, January - June 1944

WO.171/620 22nd Armoured Brigade, July - December 1944

WO.171/623 27th Armoured Brigade 1944

WO.171/845 13/18H 1944

WO.171/865 1RTR 1944

WO.171/884 256 Army Delivery Squadron 1944

WO.171/1256 2nd (Armoured) Irish Guards 1944

WO.205/637 Daily AFV States, Second Army Summaries

WO.205/638 AFV-RA Equipment States, August - October 1944

WO.205/639 AFV-RA Equipment States, October - November 1944

WO.291/1247 Report on visit to AA Oerlikon Crusader sites on South Coast, 3rd -5th July 1944

Various Field Trials Reports filed in WO.194

Details of production from AVIA.22/454, AVIA.22/456 and CAB.120/355

Tank Museum, Bovington. Instruction Book and Illustrated Parts List covering Crusader AA.III. The Museum’s Archives also have some Trials Reports, the RAC Half Yearly Reports and War Diaries for Royal Armoured Corps regiments for WW2.

Museé des Blindes, Saumur has a Crusader III AA Mark III on display, although I have not visited to see it.

Books

Monty’s Marauders - Black Rat and Red Fox, Patrick Delaforce. Tom Donovan Publishing Ltd 1977. ISBN 1-871085-36-5.

By Tank Into Normandy, Stuart Hills. Cassell & Co., 2002. ISBN 0-304-36216-6.

South Albertas - A Canadian Regiment at War, Donald E. Graves. Robin Brass Studio 1988. ISBN 1-896941-06-0.

Artyleria samobiezna w Polskich Silach Zbrojnych 1940-1945, Zbigniew Lalak and Andrzej Kaminski. Pegaz-Biz, Warsaw, Poland, 2005. ISBN 83-922002-5-X.

Armor Photo Gallery 6 Crusader Cruiser Tank Mk VI, Wojciech J Gawrych. Progres Publishing Warsaw, Poland. ISBN 83-916483-5-4.

Note: of the two Polish books, the Armor Photo Gallery has photos the Saumur vehicle, but the plans are not correct for an AA Mark III. Also, the Artyleria Samobiezna has incorrect plans, but does have several photos, some not of great quality, but still interesting, of vehicles in Polish service along with more incorrect plans.

Internet

Pathe Gazette archive is online, the South Alberta Regiment sequence can be viewed as a reduced-quality free download or as individual stills by going to:

www.britishpathe.com/advanced_search.cfm and entering the clip number 2121.09 Better quality footage and stills can be ordered online.

Table One - Crusader AA tanks in 21 Army Group, June 1944

7th Armoured Division - 28

11th Armoured Division - 28

Guards Armoured Division - 18

4th Canadian Armoured Division - 27

Polish Armoured Division - 0

4th Armoured Brigade - 20

6th Guards Tank Brigade - 11

8th Armoured Brigade - 20

27th Armoured Brigade - 20

31st Tank Brigade - 20

33rd Armoured Brigade - 20

34th Tank Brigade - 20

2nd Canadian Armoured Brigade – 20

Total - 252
Unit Establishment – 302


Table Two - Crusader AA tanks in 21 Army Group, 31st December 1944

7th Armoured Division - 5

11th Armoured Division (Note1) - 0

Guards Armoured Division - 2

4th Canadian Armoured Division - 10

1st Polish Armoured Division - 5

6th Guards Tank Brigade - 0

8th Armoured Brigade - 1

29th Armoured Brigade (Note 1) - 0

31st Tank Brigade - 0

33rd Armoured Brigade - 0

34th Tank Brigade - 0

2nd Canadian Armoured Brigade - 1

Czech Armoured Brigade - 0

3rd Infantry Division - 4

8 Corps - 9

12 Corps - 9

30 Corps – 5


Total - 51
Armoured Replacement Group – 2


Note 1 - at this time, 29th Armoured Brigade were not part of 11th Armoured Division, they had been withdrawn to rest and refit with Comets. 4th Armoured Brigade who at other times operated independently took their place.