Improvised vehicle armour

Improvised vehicle armour is vehicle armour added in the field that was not originally part of the design, in any sort of official up-armour kit, nor centrally planned.

Improvised vehicle armour has appeared on the battlefield for as long as there have been armoured vehicles in existence. In World War II, tank crews of many armies attached spare tracks to the hulls and turrets of their tanks. In the Vietnam War, U.S. "gun trucks" were reinforced with sandbags and locally fabricated steel armour plate.

More recently, U.S. troops in Iraq have armoured their Humvees and various military transport vehicles with scrap materials: this came to be known as "hillbilly armour" by the Americans, or sometimes "hajji armour" when installed by Iraqi contractors.

The first armoured cars to see combat were entirely improvised, although this soon changed as the war continued. A few were used by the Belgian army during the German invasion. The British Royal Naval Air Service received reports of this and converted some of their own cars. Improvised conversion continued until December 1914 when the first standardized design entered service.

Most armies involved in the conflict adopted some form of improvised armour at some point. The Home Guard in the United Kingdom equipped itself with a number of vehicles with improvised armour. Later in 1944 some Churchill tanks had sections of track attached to their existing armour to provide extra protection.M8 Greyhound armoured car crews would sometimes line the floors of their vehicles with sandbags to provide extra protection against landmines. US tanks sometimes had spare track attached to them. This was done with the M4 Sherman and Stuart tanks.

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Wikipedia