want the logistical complexity of adding another tank model to their inventory. Bradley requested 25 flail tanks and 100 Churchill Crocodiles shortly after the demonstration in February 1944 and the British War Office agreed to supply them as well as British-crewed AVREs. In the event though there was insufficient time to produce the vehicles and train the crews so on the day American forces were limited to DD tanks and their own Sherman bulldozer tanks and armoured bulldozers while 42 Assault Brigade instead of supporting the US beaches became a reserve for the British and Canadian beaches. In light of operations during the US landing on Omaha beach, Bradley's decision has been criticised as it was felt that use of the range of "Funnies" would have saved American lives. After D-Day, American forces did make limited use of the Sherman Crab mine-clearing tank. Designs The majority of the designs were modified forms of the Churchill tank or the Sherman tank. Both were available in large numbers. The Churchill had good (though slow) cross-country performance, heavy armour, and a roomy interior. The Sherman's mechanical reliability was valued. Among the many specialist vehicles and their attachments were: Crocodile: A Churchill tank modified by the fitting of a flame-thrower in place of the hull machine gun. An armoured trailer, towed behind the tank, carried 400 Imperial gallons (1,800 litres) of fuel. The flamethrower had a range of over 120 yards (110 metres), far greater than man-portable units. Regarded as a powerful psychological weapon, this flame tank proved highly effective at clearing bunkers, trenches and other German fortifications. AVRE (Assault Vehicle Royal Engineers): A Churchill tank adapted to attack German defensive fortifications. The AVRE's main gun was replaced by a petard mortar that fired a forty-pound (18 kg) HE-filled projectile (nicknamed the "flying dustbin") 150 yards (137 m); it was capable of destroying concrete obstacles such as roadblocks and bunkers. The mortar had to be reloaded externally by opening a hatch and sliding a round into the mortar tube from the hull. The crew of six were drawn from the Royal Engineers, except for the driver who came from the Royal Armoured Corps. One of the RE crew was a demolitions NCO sapper responsible for priming the "flying dustbin" as well as leading or supervising when they dismounted from the tank (easily done through the side hatches) to place demolition charges ("Wade" charges). AVREs