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Shadriss · 06-16-11, 09:49 PM

I think he was refering to IRL, TDW.

On on that front, DCs of WWII were set to detonate on timers, as I recall. All one had to know was how fast the sink rate was, so some quick calculations, and set the timer.

ALternately, they may have detonated on a pressure sensor. Since pressure is a constant as you go deeper (IE< the pressure for 100 ft will ALWAYS be the pressure for 100 feet, no matter where you are in the world...), all you'd have to do is, again, set it's depth (pressure) timer.

Accuracy is another thing altogether. Especially in that era, Active Sonars were of limited use. (Actually, that's still true today... for referance, I am an USN STS1/SS on the ALABAMA atm...). They can give a real good indication of bearing and range, but depth is pretty much a guessing game.

That said, as I kind of hinted at in my first reply, ships are known to use given depth bands. WWII boats just cruising around rarely went deeper than about 200 feet. During a periscope attack on a surface convoy or singleton, he'll stick with PD as much as possible, and then if forced go deep to the depths we talked about earlier. However, because he's speed limited (dont want to be TOO loud, after all...) his ability to change depth quickly is hampered. So, if you have a good idea of range and bearing, and a good feel for how long it's been since he left PD (or if he's still there), you can make a pretty good educated guess.

06-16-11, 09:49 PM	#7
Shadriss A-ganger Join Date: May 2009 Location: Hooper, UT Posts: 80 Downloads: 89 Uploads: 0	I think he was refering to IRL, TDW. On on that front, DCs of WWII were set to detonate on timers, as I recall. All one had to know was how fast the sink rate was, so some quick calculations, and set the timer. ALternately, they may have detonated on a pressure sensor. Since pressure is a constant as you go deeper (IE< the pressure for 100 ft will ALWAYS be the pressure for 100 feet, no matter where you are in the world...), all you'd have to do is, again, set it's depth (pressure) timer. Accuracy is another thing altogether. Especially in that era, Active Sonars were of limited use. (Actually, that's still true today... for referance, I am an USN STS1/SS on the ALABAMA atm...). They can give a real good indication of bearing and range, but depth is pretty much a guessing game. That said, as I kind of hinted at in my first reply, ships are known to use given depth bands. WWII boats just cruising around rarely went deeper than about 200 feet. During a periscope attack on a surface convoy or singleton, he'll stick with PD as much as possible, and then if forced go deep to the depths we talked about earlier. However, because he's speed limited (dont want to be TOO loud, after all...) his ability to change depth quickly is hampered. So, if you have a good idea of range and bearing, and a good feel for how long it's been since he left PD (or if he's still there), you can make a pretty good educated guess.