"These problems were greatly reduced by the latter years of the war. Torpedoes had fin stabilizers, nose drag rings and tail shroud rings added, all of which worked to slow the torpedo after it was dropped so that it struck the water nose-first and at an acceptable speed. These improved the drop characteristics such that the recommended aircraft maximum launch parameters were increased to a height of 2,400 feet (730 m) and a speed of 410 knots.
A lanyard was attached to the tail of the torpedo. When dropped, the lanyard tripped a starting lever, but a water trip delay valve prevented the combustion flask from lighting off until the torpedo had entered the water. When dropped at 150 knots or more, the torpedo would enter the water at an angle of between 26 and 30 degrees. The water needed to be at least 150 feet deep (45 m) and the torpedo assumed its preset running depth after water travel of 300 yards (275 m). The exploder mechanism was armed after water travel of 200 yards (180 m). Depth could be set up to 50 feet (15 m)."
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