Problems and disadvantages with electric torpedoes (the early ones)

[Pisces]

Originally Posted by Paul Riley

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Speed was confirmed previously as 7kts,and so I am expecting the TDC setting to also be correct.

Could you explain exactly how you confirmed the speed? Over how long? And what was the difference between periscope bearing and gyro angle at the time of fire, this 10 degrees? If you can remember. 7 knots target and 10 degrees lead suggest the TDC calculated the aim for a fast type-1 (7 knots target@ 90 AOB vs. 44knots torpedo= 9.1 degrees lead). A slow electric (30knots) would need 13.5 degrees of lead. Any chance you had selected a tube with a fast type-1 in it previously? Or else the speed of the target would have been around 5 knots (30*sin(10)=5.2). That is quite a difference, but possibly enough measurement fault if you used only the 3m15s rule.