 While the details of the ship 's fire @-@ control instruments are not fully available , it is known that the ships were fitted with a fire @-@ control director after completion . No computer was fitted at that time and data from the rangefinders had to be processed manually . Turrets 2 , 3 , and 5 were built with imported 6 @-@ metre ( 19 ft 8 in ) Bausch & Lomb rangefinders . These were felt to be inferior to the British Barr & Stroud instruments used on other ships and were removed in 1920 . They were replaced by either the British rangefinders or domestically built instruments of 6 or 8 metres ( 19 ft 8 in or 26 ft 3 in ) length . In the late 1920s the fire @-@ control systems were upgraded and additional platforms were added to the foremast to accommodate them . A pair of directors for the 12 @.@ 7 cm AA guns were added , one on each side of the forward superstructure , in the early 1930s . The fire @-@ control systems were again upgraded in the mid @-@ 1930s and directors were added for the 25 mm AA guns . Both ships had 10 @-@ metre ( 32 ft 10 in ) rangefinders installed at the top of the pagoda mast at that time . Type 21 air @-@ search radars were installed aboard the sisters in mid @-@ 1942 . 
 While the details of the ship <a href='null_genetive' title='1'><mark>'s</mark></a>fire @-@ control instruments <a href='negative_concord' title='2'><mark>are</mark></a> <a href='negative_concord' title='3'><mark>not</mark></a>fully available , it is known that the ships <a href='uninflect' title='4'><mark>were</mark></a> fitted with a fire @-@ control director after completion . No computer was fitted at that time and data from the rangefinders had to be processed manually . Turrets 2 , 3 , and 5 <a href='uninflect' title='5'><mark>were</mark></a> built with imported 6 @-@ metre ( 19 ft 8 in ) Bausch & Lomb rangefinders . These <a href='uninflect' title='6'><mark>were</mark></a> felt to be inferior to the British Barr & Stroud instruments used on other ships and <a href='uninflect' title='7'><mark>were</mark></a> removed in 1920 . They <a href='uninflect' title='8'><mark>were</mark></a> replaced by either the British rangefinders or domestically built instruments of 6 or 8 metres ( 19 ft 8 in or 26 ft 3 in ) length . In the late 1920s the fire @-@ control systems <a href='uninflect' title='9'><mark>were</mark></a> upgraded and additional platforms <a href='uninflect' title='10'><mark>were</mark></a> added to the foremast to accommodate them . A pair of directors for the 12 @.@ 7 cm AA guns <a href='uninflect' title='11'><mark>were</mark></a> added , one on each side of the forward superstructure , in the early 1930s . The fire @-@ control systems <a href='uninflect' title='12'><mark>were</mark></a> again upgraded in the mid @-@ 1930s and directors <a href='uninflect' title='13'><mark>were</mark></a> added for the 25 mm AA guns . Both ships had 10 @-@ metre ( 32 ft 10 in ) rangefinders installed at the top of the pagoda mast at that time . Type 21 air @-@ search radars <a href='uninflect' title='14'><mark>were</mark></a> installed aboard the sisters in mid @-@ 1942 . 
While the details of da ship  fire @-@ control instruments ain't fully available , it is known dat the ships was fitted witt a fire @-@ control director after completion . No computer was fitted at that time and data from the rangefinders had to b processed manually . Turrets 2 , 3 , and 5 was built wid imported 6 @-@ metre ( 19 ft 8 in ) Bausch & Lomb rangefinders . dese was felt to be inferior to the British Barr & Stroud instruments used on other ships and was removed in 1920 . They was replaced by either tdaBritish rangefinders or domestically built instruments of 6 or 8 metres ( 19 ft 8 in or 26 ft 3 in ) length . In thdaate 1920s the fire @-@ control systems was upgraded and additional platforms was added to the foremast to accommodate them . A pair of directors for theda @.@ 7 cm AA guns was added , one on each side of the forward superstructure , in the early 1930s . The fire @-@ control systems was again upgraded in the mid @-@ 1930s and directors was added fa the 25 mm AA guns . Both ships had 10 @-@ metre ( 32 ft 10 in ) rangefinders installed at the da of the pagoda mast at tdattime . Type 21 air @-@ search radars was installed aboard the sdaers in mid @-@ 1942 .