all subsequent British wartime destroyers. The ships were also armed with a quadruple bank of torpedo tubes. They were considered to be handsome ships, with a clipper bow that provided excellent seakeeping and two raked funnels and masts. They are remembered with great affection to this day. Construction The Royal Navy placed an order for seven Tribals on 10 March 1936, with a second group of nine Tribals ordered on 9 June for two flotillas' worth of ships. The Royal Australian Navy and Royal Canadian Navy both ordered a flotilla of Tribals. The eight Australian ships were to be built in Australian shipyards. Three were completed, two in 1942 and one in 1945, but the rest were cancelled. The Canadian order was for four ships from British yards in 1940 (completed in 1942 and 1943) and another four from Canadian yards at Halifax in 1942. The latter were not completed until after the war. Between 1937 and 1945, twenty-seven Tribals were built. Estimated cost per ship was around £340,000 excluding weaponry, and £520,000 overall. Modifications Wartime modifications The Royal Navy equipped the Tribal class with a comparatively heavy anti-aircraft armament; all eight 4.7in guns could engage aircraft with predicted fire using the FKC computer, and thus provide a powerful augmentation to the battle-fleet's AA defence. The close range AA armament of a quad 2pdr and two quad Vickers machine guns was a marked advance over previous destroyer classes and heavier than most other nations' close range destroyer armament in 1939. However, prewar, the Royal Navy assumed that destroyers would be acting mainly as escorts for the battle-fleet, and would not be the primary focus of aerial attack and would not require more than 40-degree elevation for the main armament. Events soon showed that destroyers often functioned independently and so became the main target of Luftwaffe attack, especially by dive bombers. After the loss of Afridi and Gurkha, the remaining ships were taken in hand to improve the situation. Each ship's 'X' turret, which held a 4.7-inch mounting, was removed and replaced by two QF Mark XVI guns on the twin HA/LA Mark XIX mounting. The mainmast was cut down and the rear funnel was lowered to improve the arcs of fire for the anti-aircraft weapons. As they became available, the more effective 20 mm Oerlikon guns were added, at first adding to and eventually replacing the .50 in./12.7 mm machine