Specification Crew : 5 Engine power : 600 hp Combat weight :33,050 kg (72,875 lb) Max speed : road 24 km/h (14.90 mph) Length : 8.14 m (26.73 ft) Range : 193 km (119.85 miles) Width : 2.90 M (9.51 ft) Main gun : 17-pounder(76.2 mm) Height : 2.77 m (9.10 ft) Armour : 20 mm (0.79 in) to 102 mm (4.02 in)

It was soon clear that a version of the Centaur/Cromwell able to carry the 17-pounder(76.2 mm)anti-tank gun would be necessary to counter the new German heavy tanks.The result was the A30 or Challenger.Design work began in May 1942 but the 200 ordered were not ready until mid 1944.Even then they could not take part in the Normandy landings as no provision had been made for the wading equipment. The Challenger had a lengthened hull with an extra road wheel and a widened center section for the bigger turret ring needed for the gun.The long 17-pounder gun demanded a taller turret as it had to accommodate an extra loader to handle the large ammunition,the hull machine gun was deleted even then it only carried 42 rounds.The design emerged overweight so some armour had to be removed rendering the Challenger unable to operate in close association with Cromwells as had originally been intended.By the time it was ready the Challenger was rather redundant as the Sherman Firefly was already in widespread use in the role for which it was intended.