Powerful-class
Diadem-class
Laid down at Pembroke Dockyard, England on 2 December 1895, launched on 30 April 1897, completed on 5 September 1899, converted into a training ship and renamed Powerful II on 23 September 1913, renamed Impregnable II in November 1919, renamed Defiance on 20 January 1931 and sold to be broken up in 1956 which was executed in Belgium.
Part of the Diadem-class protected cruisers consisting of the Diadem, Amphitrite, Andromeda, Argonaut, Ariadne, Europa, Niobe and Spartiate, preceded by the Powerful-class and succeeded by the Cressy-class. Designed by Director of Naval Construction at the Admiralty (1885-1902) Sir William White (2 February 1845 Plymouth, England-27 February 1913 London, England) and in fact a simplified Powerful-class design with a reduced speed, horsepower, thickness of the protective deck and lighter armed. Their main task was protecting the merchant shipping and for this purpose the Diadem-class had to be strong enough to deal with all existing foreign cruisers.
General technical class specifications. Displacement 11.000 tons and as dimensions 132,6-140,97 (over all) x 21,0 x 7,7708,38 metres or 462.6-453 x 69 x 25.6-27.6 feet. Crew numbered 677 men. Armament consisted of 16x1-15,2cm/6” quick firing guns, 14x1-7,6mm/12pd quick firing guns, 3x1-4,7cm/3pd quick firing guns, 8 Maxim machineguns and 2-45cm/18” submerged torpedo tubes. The Harvey Nickel steel (except for the decks) armour consisted of casemates and gun shields with a thickness of 11cm/4.5”, hoists protected by 5,1cm/2”, the conning tube 5,1cm/2” (aft)-15cm/6” (tube fore)-30cm/12” (fore and further more 4cm/2,5”-10,2cm/4” thick decks. Machinery consisted of triple expansion steam engines and Belleville water tube boilers. Range with a speed of 19 miles and a coal bunker capacity of 1.900 tons was 2.000 nautical miles.
