OPERATOR’S HANDBOOK Medium Mark A Whippet

The Medium Mark A Whippet tank complemented heavier British tanks with battlefield speed & firepower

Inside Britain’s WWI engineering marvel

Following the introduction of the tank to the battlefield at the Somme in autumn 1916, British tacticians realised that the armoured vehicles might indeed breach German lines and end the stalemate on the Western Front in

World War I. However, due to their slow speed and ponderous weight, their heavy Mark I, IV and V tanks were incapable of rapidly exploiting these initial gains, which allowed the enemy to re-establish defensive positions quickly.

The solution was the

Mark A Medium Whippet.

In relative terms, the Whippet was conceived as a medium tank that operated as battlefield cavalry, rapidly pouring through breaches in enemy lines created by the heavy tanks and sowing chaos in rear areas. Utilising speed and four mounted machine guns that covered a 360-degree field of fire, the Whippet was a resounding success.

The origins of the Whippet lay with engineer William Tritton, a pioneer in British tank development. In October 1916, Tritton proposed to the British military’s Tank Supply Committee a lighter, faster tank that would take advantage of battlefield breakthroughs achieved by the heavy tanks. A month later, the concept of the ‘Tritton Chaser’ was approved. The prototype was ready by the following spring and field trials were conducted in March at Oldbury, near Birmingham.

Subsequently, Field Marshal

Sir Douglas Haig, commander of the British Expeditionary Force in France, personally ordered the production of 200 Whippets, for delivery at the end of July.

The first operational Medium

Mark A tanks were delivered to F Battalion of the Tank Corps in December 1917. Production was limited to only 200 tanks and concluded in the spring of 1919, as rival designs were conceived to supplant the original Whippet. All were manufactured at the Wellington Foundry of William Foster and Co. Ltd., in the East Midlands city of Lincoln.

“BRITISH TACTICIANS REALISED THAT THE ARMOURED VEHICLES MIGHT INDEED BREACH GERMAN LINES AND END THE STALEMATE ON THE WESTERN FRONT IN WORLD WAR I”

“SIZABLE MUD CHUTES ALONG THE FLANKS AND REAR CHANNELLED MUD AWAY FROM THE ROLLERS AND TRACKS, IMPROVING MOBILITY”

DESIGN

The Whippet design included shorter tracks, which dispelled the belief that the tracks had to be as long as the hull in order to ensure maximum capability to exit shell holes or traverse trenches. Sizable mud chutes along the flanks and rear channelled mud away from the rollers and tracks, improving mobility. The fuel tank was forward in the chassis, which was originally unsprung. In

1918 Colonel Philip Johnson modified a Whippet, adding traverse leaf springs beneath the hull and a V-12, 360-horsepower Rolls-royce Eagle aircraft engine, increasing top speed to 48 kilometres per hour (30 miles per hour). However, these modifications were too costly for production.

“THE GUNS WERE REMOVABLE FROM THEIR INTERNAL MOUNTS”

ARMAMENT

The light Hotchkiss M1909 machine gun was manufactured in Britain with the label ‘Mark I’, and 40,000 were completed. The Medium Mark A Whippet was armed with four of the .303-calibre weapons, with a maximum range of 3,800 metres (4,160 yards) and a rate of fire of up to 600 rounds per minute. The Hotchkiss was gas-operated and air-cooled. Fed by a 30-round strip initially and later by belt, it was sometimes prone to jamming, and parts were difficult to replace. The guns were removable from their internal mounts, and occasionally a fourth crewman was aboard the Whippet to operate one or more of the weapons.

“COMBINED WITH THE ACRID ODOUR OF GUNPOWDER, THE NOXIOUS FUMES WERE CAPABLE OF INCAPACITATING CREWMEN AT TIMES”

ENGINE

The Tylor Co. traced its origins to the mid 18th century. Its twin four-cylinder, side-valve JB4 petrol engines powered the Medium Mark A Whippet, generating a combined 90 horsepower and a top speed of 13.4 kilometres per hour (8.3 miles per hour). The Whippet’s performance was more robust than heavier tanks, particularly considering its comparable weight of 14 tons. The Tylor JB4 engine was similar to those that powered the double-decker buses through the streets of London, and each engine was paired with one of the Whippet’s tracks. A complex steering system controlled the throttles of each engine, allowing the driver to execute turns.

CREW COMPARTMENT

Early considerations for the Whippet involved a rotating turret, but that idea gave way to a fixed, polygon-shaped crew compartment, raised to the rear of the chassis and incorporating vision slits. Inside, the compartment was cramped, dark and noisy. Heat from the engine often created extremely high temperatures inside. The compartment was situated behind the engines, and exhaust fumes regularly trailed inside via its ventilation system. Combined with the acrid odour of gunpowder, the noxious fumes were capable of incapacitating crewmen at times. The three-man crew consisted of a commander, gunner and driver, who sat forward and steered by means of a wheel. Although space was limited, sometimes a fourth crewman was added.

British crewmen pose atop the turret of a Whippet during exercises. The tank proved a valuable asset as the Allies attempted to break the stalemate on the Western Front

This Whippet demonstrates the tank’s capability to traverse a muddy landscape. The Whippet employed shorter tracks than other tanks, improving earlier designs

Soldiers relax by their Whippet tank somewhere near the front lines. The tank fulfilled its mission of exploiting breaches in enemy defences with rapid mobility The Whippet became a distinctive sight on the battlefield, with its turret at the rear of the chassis and twin engines forward of the crew compartment The Whippet stood high off the ground, its squared turret constructed of riveted plates to provide protection against smallarms fire

Four French-designed Hotchkiss .303-calibre machine guns, manufactured under licence in Britain as the Mark I, were installed aboard the Whippet

A Whippet sits idle on the Western Front while a crewman reclines adjacent to the turret

The Tylor Co. built the JB4 petrol engines that powered the Whippet. Two of the engines were mounted in each vehicle and proved quite reliable

The cramped crew compartment of the Whippet subjected its occupants to the acrid combination of spent gunpowder and exhaust fumes