The engineering tank Churchill AVRE carried a mortar of type Petard that allowed him to fire 290-mm ammunition with a charge of 12,7 kg. The firing range of such a weapon reached 72 m, and reloading was done manually, and the loader did not have to remain without the protection of the armor case. During the landing in Normandy in June 1944 of the year and in subsequent battles, a special vehicle based on the Churchill tank proved its potential and demonstrated the ability to perform various tasks of escorting troops and ensuring their combat work. However, back in 1943, the Churchill AVRE project was criticized. A number of features of this engineering tank did not receive the approval of the British military. To correct the shortcomings proposed in the new project of a similar purpose.
Potential operators in the first place did not accept the characteristics of the Petard mortar. When using ammunition of acceptable power, the gun did not have high firing rates and ease of operation. To carry out the shot, one had to approach the target on 70 m or closer, which was associated with risks. During the reloading of the gun, the loader remained under the protection of the hull and the wings of its hatch, but still there were high risks. Thus, in the new project, which received the designation Churchill Ardeer Aggie, it was necessary to increase the firing range of a subversive charge, as well as to increase the safety of the crew. These were the goals of the new project.
The only prototype of the tank is the Churchill Ardeer Aggie. Photo Shushpanzer-ru.livejournal.com
Preliminary studies of the new project have shown that when creating a new car for the Royal Engineers Corps, one can do without reworking the combat compartment. The hull, power plant, chassis and other elements of the chassis could be borrowed from serial technology without changes. In addition, it was possible to use the existing tower, the design of which should have made some minor changes.
The chassis of the Churchill tank had a classic layout with a front control compartment, a fighting compartment in the center of the hull and an engine compartment in the stern. A curious feature of the tank was the use of a large-width hull with developed onboard niches. These parts of the hull were covered by a caterpillar, which made it possible to increase the size of the internal volumes of the hull to the maximum possible values without adversely affecting other features of the machine.
The tank was equipped with a Bedford Twin-Six petrol engine with horsepower 350. and a mechanical transmission that transmits torque to the rear drive wheels. To simplify the control of the machine, some elements of the transmission were equipped with servo drives, which reduce the effort on the levers. With a tank mass of about 38, the existing engine could provide acceptable, according to the customer, mobility characteristics. The maximum speed on the highway reached 25 km / h, on rough terrain the speed decreased.
The tank "Churchill" had a recognizable chassis, the design of which was connected with the original architecture of the hull, equipped with large side niches. On the sides of the hull, there were 11 dual support rollers on an individual spring suspension. In the front of the hull, on the remote systems, the guide wheels were mounted, in the stern - leading wheels. The caterpillar covered the side of the hull. Its upper branch was supposed to move along the guides on the roof of the hull side niche.
Heavy infantry tank "Churchill" modification Mk.III, which became the basis for engineering vehicles. Photo of Wikimedia Commons
The Churchill Mk.III type armored vehicle was chosen as the basis for an engineering tank. This tank had a welded turret in which an 57-mm QF 6 pounder cannon was mounted. Also in the tower there was a twin machine gun rifle caliber, sighting equipment and other necessary devices. The new project envisaged the use of the existing tower, but the internal volumes of the fighting compartment were to be redone very seriously.
The short-barrel Mortar Petard, used on the Chirchill AVRE engineering tank, could have thrown 290-mm ammunition only on the 70-72. The new military machine of military engineers had to send a similar projectile for a long distance, for which it was necessary to create the required weapon. The development of such a system has proven to be very difficult. A large-caliber gun, proposed for installation on an existing tank without significant modernization, should have appropriate recoil parameters and some other features. In addition, it was necessary to provide loading without the need to go beyond the protected volume. As a result, it took to introduce some new ideas.
Preliminary studies have shown that acceptable returns can only be obtained through the use of a new original recoilless rifle. In this case, it was possible to reduce the load on the design of the base machine, as well as to provide the required firing characteristics. However, the development of a new recoilless weapons failed to complete immediately. After completion of the project, it was necessary to change the design of this tool in order to achieve the required characteristics.
A new gun was proposed to be installed in the existing turret, along its longitudinal axis. At the same time, there was an embrasure in the frontal parts of the tower for withdrawal of the trunk, and in the stern sheet there should have been a nozzle for ejection of powder gases compensating recoil. This design of the tower and guns allowed for circular guidance in a horizontal plane, as well as raising the barrel to small elevation angles.
In the new project, it was proposed to use the existing missile disruptive charge created earlier for the engineering tank Churchill AVRE. The product, which had the informal name of Flying Dustbin (“Flying garbage bin”), was a design of two cylindrical shells with a disruptive and propelling charge, connected by a longitudinal rod. The ammunition had a caliber 290 mm and weighed 40 pounds (18,15 kg). The mass of the warhead was 28 pounds (12,7 kg).
Engine tank, side view. Photo by Chamberlain P. Ellis C. Churchill and Sherman Specials // AFV Weapons Profile №20
For use with the new recoilless gun, the “Urn” was equipped with sealing belts, due to which the caliber was increased to 300 mm and the weight increased to 20 kg. The task of these additional details was the elimination of gas breakthrough when firing in order to increase the muzzle energy and increase the firing range. No other modifications of the munition were envisaged, since the characteristics of this product were initially considered sufficient to solve the assigned tasks.
The gun for the Churchill Ardeer Aggie tank received a smooth barrel caliber 300 mm long 10 caliber. Inside the tower was placed the breech of the barrel with systems that allow it to separate from the nozzle for recharging. It was proposed to place the ammunition with the standard and additional propelling charges in the barrel chamber, after which the barrel and nozzle could be connected to execute the shot. When firing the shot, the “Flying urn” was supposed to pass through the barrel and head towards the target, and some of the powder gases were discharged through the turret of the turret.
According to reports, during the development of a new gun, British designers faced serious problems. So, it turned out that throwing an 18-kg ammunition with a recoilless weapon requires an extremely large charge of gunpowder. When using the existing design, the separate loading shot was unacceptably large and heavy. As a result, it was impossible to place acceptable ammunition inside the fighting compartment, and working with such items inside the fighting compartment was extremely difficult.
A way out of this situation was found. It was proposed to use anti-mass when shooting. Together with the ammunition and propellant charge in the gun should load a bag of sand of appropriate size and weight. When fired, he had to lock the barrel for some time, allowing the propellant charge to create the required pressure and throw the projectile. Then the anti-mass flew out of the nozzle, ensuring the removal of powder gases and compensating for the recoil momentum.
The use of sandbags, according to calculations, significantly reduced the size of the propellant charge. Moreover, in this case, it was possible to bring the size of the ammunition to usable values. The updated version of the gun suit the developers, after which they completed the design, and also began preparations for the construction of an experienced engineering tank.
The first prototype of the Churchill Ardeer Aggie was built in 1943 year. It was the chassis of the Churchill series version of the Mk.III with a modified turret, in which a new type of 300-mm recoilless gun was installed. In this form, the car went to the field tests, which were supposed to demonstrate the capabilities of technology.
Modern layout of the Churchill Ardeer Aggie, view of the stern. You can see the nozzle guns. Photo Militarymodelling.com
Due to the absence of changes in the chassis design, the mobility of the tank remained at the existing level. He was still able to move along highways and rough terrain, cross trenches and wade shallow water. However, the focus of the tests was not on mobility, but on firepower. Test firing showed that the new gun allows you to send upgraded Flying Dustbin ammunition to 450 yards (410 m). Thus, in comparison with the previous Churchill AVRE machine, the firing range was increased several times.
However, it was not without claims. During the tests, it turned out that the 300-mm recoilless gun was too large for the existing tower. There was not much space left for crew accommodation, which did not contribute to the convenience of his work. The loading of a weapon with sequential loading into the barrel of ammunition, propellant charge and anti-mass in the conditions of a close tower was difficult. In addition, there were significant risks associated with contact with the barrel and other implements of the gun. During firing, parts of the gun were heated, which could lead to burns, and accidental contact of the barrel during a shot threatened with a contusion or other injuries.
The situation was no better outside the tank. During the shot, the high-speed incandescent powder gases, as well as the anti-mass in the form of a bag with sand in general or in a torn state, were to emerge from the stern nozzle of the tower. Due to the large caliber of the gun, the plume of powder gases flew to a distance of several tens of meters, which was a great danger to everyone around. Under the conditions of joint work of sappers and infantry, this could lead to injuries or even the death of their own soldiers. Technique with such features could not be recommended for adoption.
According to some data, according to the test results, an attempt was made to improve the design of the gun and thereby secure the troops interacting with the Churchill Ardeer Aggie tanks. On the stern of the tower, next to the nozzle, a box-shaped unit was installed with a sloping back sheet, which was supposed to discharge powder gases back and up. Thanks to this equipment, a characteristic plume was to remain behind the tank during the shooting, but the risks to the troops were reduced. Also, apparently, during the modernization, an experienced tank received two sets of smoke grenade launchers mounted on the front of the turret.
There is information according to which the updated Churchill Ardeer Aggie with a gas exhaust system has been tested, but did not interest the military. The exact reasons for this decision, based on the results of new tests, are unknown. Probably, the proposed modernization has reduced the risks for infantry, but the working conditions of the own crew of an engineering tank still remained unacceptable.
The Churchill-based museum engineering tank is supposedly the prototype of Churchill Ardeer Aggie. Photo Network54.com
An attempt to create a new weapon for throwing explosive charges, intended for the destruction of enemy barriers and fortifications, was not crowned with success. An engineering tank with an 300-mm gun went to the ground and showed a significant increase in firing range. At the same time, the car had a number of characteristic flaws that prevented its operation outside the site. Moreover, some design problems made it difficult to use such equipment in any conditions.
The project of the engineering tank Churchill Ardeer Aggie did not interest the potential customer in the face of the Royal Engineers Corps. The first prototype, built and tested in the 1943 year, also became the last car of its type. The command of the Royal Engineers Corps decided that Churchill AVRE machines would be sufficient for solving the existing tasks. Until the end of the Second World War, the industries of Canada and Great Britain managed to produce several hundred of such machines that were actively used during the battles.
There is information according to which the only built engineering tank Churchill Ardeer Aggie is preserved and is still in one of the British museums. Allegedly, a unique machine is stored at one of the sites of the Museum of the Royal Engineers Corps in Chatham. There are several snapshots of this sample taken through a mesh fence. For some reason, the tank is not included in the main exhibition and is not available to visitors of the museum under normal circumstances, which is why fans of technology had to photograph it through the fence. Characteristic features of this tank are a large box at the stern of the turret, which can be a gas exhaust system, as well as smoke grenade launchers on the sides of the turret.
However, there is reason to doubt that this is Churchill Ardeer Aggie. Some features of the car’s appearance suggest that this is the Churchill AVRE engineering tank of a late (possibly post-war) modification with a new type of weapon. Which of the versions is true - is unknown. Unfortunately, the British Museum is in no hurry to clarify the details.
Regardless of what kind of armored vehicle is located in Chatham, the Churchill Ardeer Aggie project did not give noticeable results. The only sample of such an engineering tank showed a relatively high firing range with questionable operating features. As a result, the tank did not go into mass production and could not supplement or replace the Churchill AVRE that was in service. Despite the successful solution of the main tasks of the project and the superiority in the main characteristics, the new version of the engineering tank could not go beyond the landfill.
On the materials of the sites:
Chamberlain P. Ellis C. Churchill and Sherman Specials // AFV Weapons Profile No. XXUMX. Profile Publications. 20.