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The 1915 Davidson-Cadillac Armoured Car - which had the distinction of being the first fully armoured motor vehicle to be built in the U.S.A. - was similar in layout to some of the early Royal Navy Air Service armoured cars built in October 1914. Armoured all round with controllable radiator doors, the rear part had an open top, where the Colt machine-gun with an armoured shield was mounted just behind armoured head cover for the driver. The Cadillac was a much better designed vehicle than the R.N.A.S. cars, however, (there was, of course, less urgency involved) with a lower centre of gravity and although only, like them, a conventional passenger car chassis with drive to the rear wheels, had a better cross-country performance.
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