 The trials conducted by the NII VVS included engagements between the Tu @-@ 12 and the Soviet MiG @-@ 9 and Yak @-@ 23 jet fighters which were very useful in evaluating the offensive armament of the fighters , the defensive armament of the bomber and the proper tactics involved for both types of aircraft . The tests demonstrated the inferiority of the current 12 @.@ 7 mm ( 0 @.@ 50 in ) armament and meant that every Soviet bomber henceforth would have a defensive armament using power @-@ operated turrets that carried guns 20 mm or larger . 
 The trials conducted by the NII VVS included engagements between the Tu @-@ 12 and the Soviet MiG @-@ 9 and Yak @-@ 23 jet fighters which <a href='uninflect' title='1'><mark>were</mark></a> very useful in evaluating the offensive armament of the fighters , the defensive armament of the bomber and the proper tactics involved for both types of aircraft . The tests demonstrated the inferiority of the current 12 @.@ 7 mm ( 0 @.@ 50 in ) armament and meant that every Soviet bomber henceforth would have a defensive armament using power @-@ operated turrets <a href='null_relcl' title='2'><mark>that</mark></a><a href='been_done' title='3'><mark></mark></a> carried guns 20 mm or larger . 
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