How does a submarine plot a target

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mwindsorfw
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How does a submarine plot a target

Post by mwindsorfw »

One of my favorite aspects of WitP is submarine warfare. However, this raised a question. How does a WWII-era submarine plot a target? I've seen movies (Run Silent, Run Deep and Das Boot) where they call out range, speed, and bearing, draw on a chart, and then fire. Is the sub commander just eyeballing range, bearing, and speed? Maybe someone could direct me to a resource that would explain what is going on.

Thanks.
-Mike
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Tankerace
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RE: How does a submarine plot a target

Post by Tankerace »

This applies to a US sub using a Mk 1 Torpedo data computer.

Captain sights a target. Using a Japanese ship identification handbook, the commander gets a rough idea of the size of the ship. He uses this to guess (yes, guess) the range of the ship (If the sub has SJ radar, then he can use its radar bearing to get the range). He calls out the range, and the bearing. Bearing is determined by looking at the top of the scope. Numbers on their indicate the degree bearing on the scope in relation to the front of the sub.

Speed is determined by the bow and stern wakes, plus how oftern the CO must move his scope. The larger the wakes, andthe more the CO has to move the scope, the faster the target is going.

The entire process is guesswork, and the majority of the time the numbers are wrong. That is why wou fire a spread. You fire 4 torpedoes, angled a few degrees apart, at where a target SHOULD be, and with luck 1 or 2 might hit.

If you want to do it all manually, I suggest you take a calculus class, because you have to figure target course and speed, your course and speed, torpedo speed, distance, etc etc. Very very hard work. The TDC was a life saver.
Designer of War Plan Orange
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Author of Million-Dollar Barrage: American Field Artillery in the Great War coming soon from OU Press.
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Kwik E Mart
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RE: How does a submarine plot a target

Post by Kwik E Mart »

....ironic you should call it a "life saver" [8|]
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Tankerace
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RE: How does a submarine plot a target

Post by Tankerace »

Well, I dunno about you, but if I had to do all those calculations by hand, I'd just open the hatch and say to heck with it, so ya, a life saver [:D]
Designer of War Plan Orange
Allied Naval OOBer of Admiral's Edition
Naval Team Lead for War in the Med

Author of Million-Dollar Barrage: American Field Artillery in the Great War coming soon from OU Press.
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kaleun
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RE: How does a submarine plot a target

Post by kaleun »

Brits used a mechanical device called "Is-Was" after figuring (i.e: guessing) the location and speed of the target, the thingie would figure out (i.e. guess) where it was before, and give you the course of the target. Then the inspired skipper would go "fire one..." and the extra would intently gaze into a stopwatch.[8|]
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