WW2 British Prototypes

Praying Mantis

United Kingdom (1937-1944)
Experimental Machine Gun Carrier – 2 Prototypes Built

The Praying Mantis was an experimental machine gun carrier designed by a private developer for the British Army during the Second World War. It is in competition with the Kugelpanzer as one of the strangest armored vehicle designs ever produced.

It could be said that it is ‘typically British’ in its eccentricity. The vehicle would never become as deadly a hunter as it’s invertebrate namesake, however, as it never left the prototype stage.

The First prototype of the vehicle.


The Praying Mantis was a private venture by one Mr. Ernest James Tapp (often shortened to E. J. Tapp) of County Commercial Cars. The design was patented in 1937, with the construction of prototypes beginning in 1943. The vehicle was designed to shoot over walls and other obstacles while staying as concealed as possible.


The initial prototype of the Mantis was designed on a bespoke chassis. It had thin tracks, a rear mounted drive wheel and 4 road-wheels. The prototype was basic in its construction, intended just as a means of testing cross-country ability and the driver’s position. This prototype was displayed to the War Office shortly after the outbreak of World War II.
The second and final prototype was commissioned in 1943 and was based on the engine and running gear of the venerable Universal Carrier. The Universal Carrier was the workhorse vehicle of the British Army throughout the war and saw service with numerous countries in numerous theaters. It also spawned a number of variants and derivatives such as the Canadian Wasp flamethrower or the Australian 2-Pounder armed LP2.
With this, the Mantis retained the Carrier’s Ford V8 85bhp petrol engine and running gear that used the ‘track-bending’ steering system. This is all that the Mantis retained from the Carrier, as the rest of the tank’s chassis was rather unusual.


The anatomy of this ‘iron invertebrate’ is unlike any other tank or armored fighting vehicle. It consists of a lower hull in which can be found the engine, a crew compartment, a pivoting ‘head’ and finally, a small machine gun armed turret, known as the ‘helmet’.

The Praying Mantis with the fighting compartment raised to full extension. Photo: The Tank Museum
The Crew compartment, known as the ‘control chamber’ took the form of a long hollow box. Inside would be the positions for the vehicles two crew members, the Driver and the Gunner, who would be effectively lying down, prone, inside the box with their heads towards the machine gun turret. At the crew’s feet was a hydraulic system that would raise the entire compartment. It would rise to about a 55-degree angle. Maximum elevation was 11f.5ft (3.48m) off the ground. In the original plans, the box had the ability to traverse left and right as well. This would bring the head, which could pivot up and down, above an obstacle allowing the gunner to engage any targets. The vehicle could move around with the crew chamber in any position. When fully lowered, the Mantis could move around behind low bushes, or even tall grass while staying concealed.
The Gunner was in charge of the vehicle’s main armament, a pair of Bren Light Machine Guns mounted side-by-side in the rotating ‘helmet’. Chambered for the standard British .303 round, the magazine fed Bren was a staple weapon of the British Army’s infantry. The gun entered service in 1938. It would serve for over 30 years, finally being withdrawn in 1991. The ‘helmet’ was also equipped with a grapple, fired by a small grappling gun.

Praying Mantis illustration
Illustration of the Praying Mantis by Tank Encyclopedia’s own David Bocquelet


The second prototype took part in a number of trials, but that’s as far as it would go. In operation, it was found that the controls were extremely hard to use. The effect on the crew was also not ideal, as many recounted the swaying of the moving vehicle gave them motion sickness. In 1944, it was officially abandoned.

Lowered fully, the Mantis could be used as cover for infantry. Photo: The Tank Museum
The first prototype was scrapped, but the second eventually found it’s way to the Bovington Tank Museum. The vehicle has been preserved there ever since, and the joints are still in operable condition. It is considered to be the strangest vehicles in their collection.
Though this vehicle was something of a flop. Mr. Tapp’s idea of a vehicle that could raise its weapons above cover without exposing itself would later be employed by various armored vehicles. The ATGM (Anti-Tank Guided Missile) launching FV1620 Humber Hornet, for example, used a similar mechanism.

The Praying Mantis as it sits today in The Tank Museum, Bovington. Author’s photo.

An article by Mark Nash


Crew 2 (driver, machine-gunner)
Propulsion Ford T 4-cyl petrol, 40 bhp
Speed (road) 25 mph (40 km/h)
Armament 2 x .303 Bren Light Machine Guns
Armor 6 to 9 mm (0.24-0.35 in)
Total production 2 Prototypes

Links, Resources & Further Reading

Article on The Tank Museum’s Website
Patent GB577274 submitted on July 16th 1946 by Mr. E. Tapp

By Mark Nash

Member since 2016. Specializes in weird. 120 articles & counting...

2 replies on “Praying Mantis”

The Praying Mantis – I worked for County Commercial Cars and met Mr Ernest Tapp shortly before he died, in 1964 I think.
I have never seen the videos of development testing before and am amazed at the vehicles performance. I must now resolve to visit Bovington and see it for myself !!!
Kindest regards

Geoff Penn

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