The disastrous Dieppe Raid of August 19th, 1942, forced a great deal of reevaluating as to how combat engineers would operate on the battlefield. A Canadian Officer of the Royal Canadian Engineers, John James Denovan, began work on developing an armored vehicle that would allow them to carry out their objectives, but remain protected.
Denovan worked at the Special Devices Branch of the Department of Tank Design (DTD) in England alongside the Assistant Director of the Branch, Lieutenant Colonel George Reeves. Reeves had been an observer at the Raid on Dieppe, and noted just how difficult it was for engineers to clear the anti-tank obstacles on the beach under heavy fire, which kept the attacking tanks pinned down on the beach. The Lieutenant Colonel decided to base this new armored vehicle on the Churchill Infantry Tank. With this idea, the ‘Armoured Vehicle Royal Engineers’, or ‘AVRE’ was born.
Wounded soldiers taking shelter behind a Churchill AVRE on Juno beach. Photo: www.tank-hunter.com
The Churchill Tank
Officially designated as ‘Tank, Infantry, Mk. IV, A22’, the Churchill entered service with the British Armoured Forces in 1941. It was named, contrary to popular belief, after an ancestor of the famous Winston Churchill, not the man himself. It was the last ‘Infantry Tank’ to serve in the British Military. Churchills were well armored. The thickness of the armor would increase with subsequent models of the tank. At its thickest, Churchill Mk. I had 102mm (4.in) of armor. This increased to an impressive 152mm (6in) with the Mk. VII.
The Churchill went through a number of upgrades to its main armament throughout its service. Churchill Mk. I and IIs were armed with a 2-Pounder (40mm) gun, the Mk. III and IVs were armed with a 6-Pounder (57mm) gun and the Mk. VI and VIIs were armed with a 75mm (2.95in) gun. The Mk. V and VIIIs were designed as Close Support (CS) tanks, so they were exclusively armed with a 95mm (3.7mm) Howitzer.
The Churchill was not fast. A lumbering beast at approximately 40-tons, its top speed was only 15 mph (24 km/h). It was powered by a Bedford 12-cylinder engine producing 350 hp. The tank was supported on a complicated suspension with 11 small wheels per side, each one attached to an independent coil spring. The drive wheel was at the rear with a sprocketed idler at the front. Though it was slow and heavy, the Churchill made a name for itself as being one of the best cross-country tanks ever built and could climb higher gradients or cross harder obstacles impassible to most other tanks then in service.
The Churchill served for the remainder of the Second World War, and even saw action in the Korean War. The Infantry Tank version of the Churchill was officially removed from service in 1952.
Development of the AVRE
Development started on modifying the Churchill in October 1942. To demonstrate the basic layout of equipment and stowage areas, the inside of a standard Churchill was completely stripped out. These areas had to hold explosives, charges, fuses, and various other pieces of equipment essential for Royal Engineer operations.
Plans for the tank escalated quickly. It was decided not only to make the vehicle a kind of armored personnel carrier but also give the Engineers the ability to project a large high-explosive charge, giving the crew the ability to destroy targets without having to dismount the tank. For it to be effective, the propelled charge would have to be a large one capable of cracking concrete or clearing a large gap in any obstacle. The resultant weight of such a charge was a problem, however, and was beyond the capacity of any available gun. Trying to fit a large, traditional type howitzer into the rather small turret of the Churchill would also be a hard task.
Denovan chose a spigot mortar for the main armament of the AVRE. This type of weapon, most famously exampled in the PIAT (Projector, Infantry, Anti-tank) infantry anti-tank weapon. This type of mortar works in reverse to a normal gun. The bomb contains a hollow tube that fits over a rod, known as the spigot. There is a propelling charge at the end of the tube and a firing pin within the spigot. When the charge is detonated the bomb is fired off, with the propellant gas expanding between the spigot and the hollow tube.
A crew member cleans the Mortar of a Mk. III AVRE. Note the size of the ‘Flying Dustbin’ on the man’s left. Photo: IWM
A Spigot mortar able to be mounted on the turret of a tank was designed. It was named the ‘Petard’ (a 16th-century word of French origin describing ‘a bomb to breach’) and was capable of firing huge, 40lb (18.4kg) high-explosive bombs at a short distance of 100 yards (91 meters). It was designed to blow through roadblocks, bunkers, pillboxes and other concrete, brick or earthen obstacles and defenses.
This large projectile would slide into a short barrel with a 290 mm (11 in) bore. The bomb itself was designated the ‘Bomb, Demolition, Number 1’. It would come to be known as the ‘Flying Dustbin’ due to its shape which resembled what the British call a dustbin (‘trash can’ in America). The weapon was specially designed to fit the existing mantlets of either 6-Pounder (57mm) or 75mm Gun armed Churchills. This greatly simplified production as no alterations would have to be made to accommodate the new weapon.
A disadvantage to the weapon, however, was the fact that the loader’s hands would have to be exposed when reloading the mortar. Not ideal in combat situations. To begin loading, the turret would be traversed so the Petard was over the bow gunners position. This man would then slide open his hatch (which replaced the two-part hatch on standard Churchills) and reach up to the barrel of the Petard. Like a giant shotgun, the barrel would be broken in half, and a fresh round inserted.
This photo shows the loading sequence of the Petard. Photo: The Tank Museum
Firing the round was achieved via a large spring loaded rod. Upon the trigger being pulled, this large firing pin would strike and ignite the propellant charge in the back of the mortar bomb, sending it flying out of the stubby barrel.
The AVRE retained the standard secondary armament of a coaxial and a bow mounted BESA 7.92mm Machine Guns.
Following a successful demonstration of the weapon, the War Office approved the production of the vehicle on the 14th January 1943. The AVREs would be based on the Mk. III (welded-turret) and IV (cast turret) Churchill.
AVREs would also carry various other pieces of equipment to assist their comrades on the battlefield. These included fascines. Fascines had been carried by tanks since their earliest days on the devastated battlefields of the First World War, most notably at the Battle of Cambrai in 1917. Fascines are used to fill wide trenches or ditches to allow tanks to cross. They are usually fabricated from brushwood, bound tightly together into a cylinder. These wooden fascines were around 8 feet (2.4 meters) in diameter and approximately 12 feet (3.6 meters) wide.
The Fascines would be carried on the front of the tank over the driver and co-driver position on a wooden cradle. The Turret had to traverse to the left or right to facilitate this. It would be tipped off into the offending ditch when required. Sometimes, the bundles would be carried on the engine deck, but this wasn’t recommended practice as the bundles could catch fire.
A fascine is loaded on to an awaiting Mk. IV AVRE. The muzzle of the Petard is tilted up in the reloading position. This photo shows both side-hatches of the Churchill open. You can see right through the vehicle. Photo: SOURCE
Small Box Girder Bridge
The AVRE was also able to carry and place the ‘Small Box Girder’ bridge. This bridge was 30 feet (9.1 meters) long and could support a 40 ton (40.6 tonne) tank. A cable and winch were attached to the engine deck, with an A-frame attached to the front of the tank. The bridge was carried hanging at the front of the tank at an angle of around 60-Degrees. The weight of this bridge hanging off the bow compressed the forward suspension bogies and lifted the rear ones off the ground. As such, driving while carrying it was not easy. The bridge would be lowered via the winch over small rivers, craters or other obstacles to allow other tanks and vehicles to pass.
There were attempts at carrying the bridge in other ways. These included folding the bridge in half (like a modern scissor bridge) and towing the bridge behind the tank with wheels added to the bottom of the bridge. Bridge carrying AVREs were not very popular with Captains and helmsman of landing ships as the bridges caught the wind. Having them at the front of landing ships made them hard to steer, so they were often loaded as far back on the deck as possible.
Churchill AVRE carrying a bridge. Photo: The Tank Museum
‘Bobbin Carrier’ or ‘Carpet Layer’
Another famous role for the AVRE was as the ‘Bobbin Carrier’. There were two types, the Type C and the Type D. The Type C was the smaller of the two and was carried hanging in front of the tank single arms. The Type D is the larger and most famous of the two, a was supported by a larger frame over the front end of the AVRE. Both of the Types were carried utilizing special universal mounts on the sides of the Churchill. The frame supported a large reel (or, hence the name, bobbin) of canvas matting or wooden beams. The tank would drive over the matting, laying it as it drove.
The Type D would be employed on soft beaches and would lay down a secure surface for following troops and vehicles to advance on. The Type C was designed to flatten down barbed wire and similar obstacles. Once the ‘carpet’ was laid, the crew could detach it from inside with blow out pins. Used ‘bobbins’ were simply discarded on the battlefield.
Churchill AVRE with the Type D ‘Bobbin Carrier’. Photo: Wikimedia Commons.
Bull’s Horn Mine Plow
Many mine plows were deisgned, tested and used with the Churchill AVREs. The Bull’s Horn, in particular, is named here because, 1: it was one of the only successful designs, and 2: it is named after the Bull’s head logo of the 79th Armoured Division. The Bull’s Horn Plow, specifically a Mk. III, was only used once in the War. This was on D-Day, on Sword Beach.
The plow consisted of a large frame carried at the front of the tank. It was connected to a winch that allowed it to be lifted for travel. There were two blades on it, each with six teeth. At the front of the of the frame was two large skids that kept the plow from digging too far into the ground. The plow lifted mines out of the ground and pushed them to the side of the tank, creating a safe lane.
The Bull’s Horn equipped on a Churchill during testing. Photo: Weapons and Warfare
Canadian Indestructible Roller Device (CIRD)
The AVRE was also able to be fitted with the interestingly named ‘Canadian Indestructible Roller Device’, also known as the CIRD. This was a mine exploding device carried on the front of the tank. It consisted of a large, simple frame. At the center, two heavy rollers were attached to tightly sprung levers. Should the rollers detonate a mine, the springs would absorb the impact.
A Mk. III AVRE with the CIRD equipped. Photo: Panzerserra Bunker
Conger Mine Clearing Line Charge
The COnger was perhaps the most dangerous (to everyone) piece of equipment carried by the AVREs. The Conger, named after the Eel, was what is now known as a ‘Mine Clearing Line Charge’. It was based on the chassis of a Universal Carrier with its engine removed so it could be towed as a trailer. The clearing device itself consisted of a 5-inch (12.7 cm) rocket and a long hose.
At a minefield, the rocket would be launched taking with it the empty hose, which would then fall over the length of the minefield. The hose would then be pumped end-to-end full of Nitro-Glycerine and detonated it. Mines in the vicinity would then detonate as result of Sympathetic detonation, clearing a path through the minefield. The Conger was one of the first of such devices to be used. Following the Conger, the British developed the Giant Viper. The US Military still uses a similar device called the M58 ‘MICLIC’. This is towed but is also mounted directly to the Assualt Breacher Vehicle (ABV).
A Mk. IV AVRE towing the Conger. Photo: The Tank Museum
Service in Brief
The AVRE’s first action would come on D-Day, the storming of the beaches that was at the core of their design. One such account from the 5th Battalion of the East Yorkshire Regiment describes one of the first actions the AVRE would engage in. The 5th Battalion had a hard fight over on the extreme left-hand side of Gold Beach at La Riviére on D-Day, where the concrete defenses had survived the shelling. After several armored vehicles had been knocked out, an AVRE appeared. A forty-pound Petard bomb was soon launched from the maw of the stubby barrel. It was a direct hit, destroying the emplacement containing the anti-tank gun which had inflicted so many losses.
A Churchill Mk. III AVRE leads a Sherman Firefly through the Bocage, 1944. Photo: Panzerserra Bunker
But the East Yorks, amid the dust and smoke from the bombardment, still needed several more hours to clear La Riviöre, house by house. Churchill Crocodiles, flame-throwing tanks, also helped, while the flail tanks of the Westminster Dragoons soon cleared the minefields.
AVREs would see service during Operation Astonia. Starting on the 10th of September 1944, the objective of this operation was to capture the French town of Le Havre. In this heavily mined area, the AVREs worked closely with Sherman Crab flail tanks which cleared a safe path. Various equipment was fielded by the AVREs in this operation, including the Small Box Girder bridge.
In action, the AVRE would work closely with the dreaded, fire-breathing, Churchill Crocodile, to combat bunkers and dug-in positions. More often than not, the psychological effect of the vehicles would be enough to beat the foe. One can only imagine the dread felt by the Germans who were being stared down by the mortar of the AVRE and the flaming nozzle of the Crocodile.
When facing a stubborn enemy bunker or position, the Crocodile would lay some flame in visual range to showcase its deadly breath. Should the position continue to stand, the accompanying AVRE would crack it open with a mortar round. The Crocodile would then proceed to cover the breached area in the flaming liquid which would then flow into the position. This method of ‘Bunker Busting’ is often to referred to as ‘Corkscrew and Blowtorch’, a phrase coined by American forces fighting the Japanese in the Pacific.
This very tactic would be employed by AVREs and Crocodiles during the Fall of Goch, a German border town, on the 20th February 1945. Goch was the final objective in Operation Veritable, and a number of bunkers and pillboxes were proving to be stubborn opponents. The 79th Armoured Division, working with the 107th Regiment of the Royal Armoured Corps (107 RAC), methodically dealt with these targets, following closely the method outlined above. Stage 1: The Bunkers would be assailed by a barrage of fire from 75mm gun armed Churchills, and 95mm Howitzer fire from Churchill Vs. Stage 2: Should the target refuse to yield, AVREs would be brought up, under cover from the gun tanks due to the limited range of the AVREs Petard. Stage 3: Should the enemy continue to stand, the Crocodiles would be called in. If the enemy did not surrender after the first burst of flame, they would never get another chance.
Two AVREs taking part in Operation Veritable in 1945 crossing boggy ground. Photo: SOURCE
AVRE vs Panther
Near Tilly-sur-Seulles in Normandy, on the 17th of June, 1944, an interesting altercation took place between a Churchill AVRE, and one of Germany’s most feared tanks, the Panzer V Panther. Fierce fighting had erupted as Allied tanks and infantry pushed down the village’s main road. One AVRE was nearing a crossroads. Its gunner, Sapper Sydney Blaskett, was spraying machine gun fire into bushes thought to be occupied by enemy infantry. Suddenly, just in front of the tank, a Panther appeared at the short range of only 50 yards.
Under orders from his commander, Spr Blaskett traversed the turret around. The cavernous maw of the 290mm Spigot Mortar was stuffed with the 40Lb “Flying Dustbin”. With a bang, the heavy projectile was hurled towards the Panther. It whirled through the air, arching straight towards the point of aim. Spr Blaskett had aimed his shot at the Panthers turret ring. The round exploded after hitting a telegraph pole three feet away from the Panther. When the explosion had cleared the Panther was still, and never moved again. The blast from the round had put it out of action.
In October 1945, at IJzendijke, a small city in Holland, the Conger showed just how deadly it could be. There were four AVREs being resupplied in a depot here in a lull during action in Operation Switchback, part of the Battle of the Scheldt. Troops were unloading Jerry Cans full of the extremely unstable and volatile Nitro-Glycerine used in the Conger from two Bedford supply trucks. During the process, the Nitro detonated. The resulting, colossal explosion vaporized the supply trucks, completely destroyed the two AVREs, claimed the lives of 47 troops, wounded 37, and also resulted in the death of the civilian inhabitants of a nearby farmhouse. As a result of this, the Conger was never used again.
This is claimed to be a photo of the aftermath of the Conger explosion, though this cannot be corroborated. In the picture though, the remains of one of the destroyed Bedford trucks. Photo: Source Unknown
Proposed Upgrade, ‘Ardeer Aggie’
Two of the major problems with the AVRE was the Petard Mortar’s limited range of 100 yards (91 meters) and the fact that it had to be loaded externally. In 1943, a new, more powerful weapon was tested. The bore was increased to 300mm, with a barrel length of 3 meters and the weapon could be loaded from inside the turret. This prototype is often erroneously referred to as simply “Ardeer Aggie” when a more accurate name would be ‘Churchill Mk.III with Ardeer Aggie’
The prototype Churchill with ‘Ardeer Aggie’ mortar. Photo: The Tank Museum
Post War, the FV3903
Such was the success of the original vehicle in the Second World War, that between 1947 and the early 1950s, 88 of the later Mk. VII Churchills were converted into a new, improved version of the AVRE, which was designated the FV3903. Even with this new generation, though, the Petard armed AVREs continued to serve until 1964. The designation of the vehicle was changed, however. The original nomenclature, ‘Armoured Vehicle Royal Engineers’ would be replaced with ‘Assault Vehicle Royal Engineers’.
A Churchill Mk. VII FV3903 AVRE named ‘Mars’, carrying a wicker fascine. Note the reward facing loudspeaker on the back of the turret. These AVREs had one of these speakers on each side of the turret so the Commander could communicate with infantry following the tank. Photo: Haynes Publishing
The biggest change came with the weaponry. The trusty 290mm Petard mortar was replaced with the new Ordnance BL 6.5″ Mk I. This 165mm bore demolition gun was a breach loader, a vast improvement over the Petard. The gun fired a 64 lb (29 kg) High Explosive Squash Head (HESH) shell at up to 2,400 m (2,600 yd). This was a huge range increase compared to the 100 yard (91 meter) range of the Petard. The round had no shell case in the traditional sense. Instead, the charge was placed inside a perforated base connected directly to the warhead.
The new AVRE’s primary role would not differ from the original. It would use its gun to breach and destroy obstacles and fortifications. Also, like the original, it could fulfill a number of other roles and carried various pieces of equipment, such as individual demolition charges carried which the crew could place by hand. The AVRE could be used as mobile crane, fascine carrier, bridge layer, bulldozer and as a tractor.
Despite work beginning in 1947, this new AVRE did not enter service until 1954. The AVRE was one of the last types of Churchill to serve with the British Army, superseded only by the mine-clearing Churchill Toad which was produced up to 1956. As far as it is known, they were never used in combat, and in 1955, work began on its replacement, the Centurion AVRE.
Fortunately, quite a large number of AVREs survive today. The most famous is the ‘Graye-sur-Mer AVRE’ in Normandy, France. This AVRE, called ‘Avenger’, belonged to the 26th Engineer Squadron, which landed on the morning of D-Day. It sank into a 4-meter deep bomb crater, concealed from its driver by the shallow flooded area that surrounded it. Four members of its 6 man crew were killed by German machine gun and rifle fire as they tried to escape. The other two were seriously injured and had to be evacuated later in the day. A bridge was laid over the sunken Churchill tank to allow Allied troops across the flooded land. The tank was used as a bridge support.
It remained buried for 32 years. In November 1976, a team of British Army soldiers and engineers extracted the Churchill AVRE tank from its wartime grave. The two surviving members of the tank crew, Tank Driver Bill Dunn, and Bill Hawkins were present when it was lifted back onto the beach. The D-Day tank unit commander General A.E. Younger was also present. Once it had been restored it was erected on a concrete plinth as a memorial to all the brave soldiers who had died or were wounded on that section of the coast on D-Day. It is situated only a few meters from where it sunk into the large flooded bomb hole.
The preserved AVRE at Graye-sur-Mer. Photo: Craig ‘Tank Hunter’ Moore
One can also be found at the Tank Museum, Bovington. It was once on display but now resides in the Vehicle Conservation Center (VCC). The disembodied turret of an AVRE can be found in the car park of the Cobbaton Combat Collection, North Devon.
Churchill Mk. IV AVRE turret preserved at the Cobbaton Combat Collection. Photo: Author’s Photo
For a time, one of the later Churchill Mk. VII FV3903 AVREs was part of the Littlefield collection, along with a Churchill Toad. However, since the collection was sold off in 2014, it is unknown what happened to the AVRE. The Toad ended up in the Australian Armor and Artillery Museum.
|Dimensions||24ft 5in x 10ft 8in x 8ft 2in
(7.44 m x 3.25 m x 2.49 m)
|Total weight||Aprox. 40 tonnes|
|Crew||5 (driver, bow-gunner, gunner, commander, loader)|
|Propulsion||350 hp Bedford horizontally opposed twin-six petrol engine|
|Speed (road)||15 mph (24 km/h)|
|Armament||290mm (11.4 in) Petard Mortar
2 x 7.92mm (0.3 in) BESA machine guns
|Armor||From 25 to 152 mm (0.98-5.98 in)|
Links & Resources
Osprey Publishing, New Vanguard #7 Churchill Infantry Tank 1941-51
Haynes Owners Workshop Manuals, Churchill Tank 1941-56 (all models). An insight into the history, development, production and role of the British Army tank of the Second Wold War.
Schiffer Publishing, Mr. Churchill’s Tank: The British Infantry Tank Mark IV, David Fletcher
Pen & Sword, Churchill’s Secret Weapons: The Story of Hobart’s Funnies, Patrick Delaforce
David Fletcher, Vanguard of Victory: The 79th Armoured Division, Her Majesty’s Stationery Office
Churchill Mk. III AVRE, identified by the square, welded turret
Churchill Mk. IV AVRE, identified by the rounded cast turret, with attached ‘Canadian Indestructible Roller Device’ or ‘CIRD’.
Illustrations by Tank Encyclopedia’s own David Bocquelet
The later FV3903 AVRE based on the Churchill VII that saw the Petard Mortar replaced with a 165mm Demolition Gun. Illustration by Tank Encyclopedia’s own AmazingAce, based on work by David Bocquelet.
British Churchill Tank – Tank Encyclopedia Support Shirt
Sally forth in with confidence in this Churchill tee. A portion of the proceeds from this purchase will support Tank Encyclopedia, a military history research project.