Jonathan_S wrote:tlb wrote:Yes, a torpedo is quieter than gunfire, but can make noise that is picked up by hydophones (such as used in sonar). As we both said, the electric torpedo makes much less noise.
For a lot of the battles it was more important that the torpedo didn't have the flash (or smoke) of gunfire. Visual detection was more of a concern because many ships didn't carry hyrophones and even the ones that did might not always have a listening watch on them -- ships relied more on active sonar (or ASDIC as the British called it) than on passive listening -- though the Germans got good use out of their ship mounted hycrophones.
And visual detection was even more likely in the early years of the war before low-flash propellant became a bit more common.
So it was generally good tactics (though often someone jumped the gun) in a night ambush to fire your topedoes first and not fire your guns until the enemy reacted or the torpedoes would have/did hit. Not only did they take longer to travel the distance to the enemy but but there was a good chance the enemy wouldn't detect them in time evade (or possibly at all). But they almost certainly wouldn't miss gunfire and, alerted to enemy presence, would almost certainly maneuver and spoil the torpedo attack.
Common practice with the PT Boats was to approach as slowly and quietly as possible to launch their torpedoes and then just as quietly turn and slowly move away from the targets. Engagements with ships and other floating things were apparently primarily in the dark. The better to hide and survive.
When/if your torpedoes hit the target or if the target suddenly got really excited and started actively looking or shooting (at anything) it was: SLAM all three engines to max and get the hell out of there. At least that was so in the Pacific. You had just used your most powerful and essentially your longest range weapon(s). Now you're a very soft if nimble target with speed & darkness as your salvation.
