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Old 04-17-08, 12:42 PM   #1
Slick Wilhelm
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How did the real submariners determine target speed?

I'm still missing a lot using manual targeting, but at least I'm getting a little bit better. It seems to me that the most difficult part is determining target speed. But I've been using Werner Sobe's "Magic Numbers" method, and that has helped quite a bit.

I've also started reading Clay Blair's Silent Victory again for the first time in about 25 years, and I've yet to see an explanation in there about how the real submariners determined target speed. At least I can take comfort in the fact that even the best skippers had patrols where they missed...a lot!

Does anyone know the method real submariners used to determine target speed? In the book there are many skippers who blame themselves for underestimating the speed of a particular target, but they don't go into detail on how that could happen.
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Old 04-17-08, 12:50 PM   #2
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Quote:
Originally Posted by Slick Wilhelm
I'm still missing a lot using manual targeting, but at least I'm getting a little bit better. It seems to me that the most difficult part is determining target speed. But I've been using Werner Sobe's "Magic Numbers" method, and that has helped quite a bit.

I've also started reading Clay Blair's Silent Victory again for the first time in about 25 years, and I've yet to see an explanation in there about how the real submariners determined target speed. At least I can take comfort in the fact that even the best skippers had patrols where they missed...a lot!

Does anyone know the method real submariners used to determine target speed? In the book there are many skippers who blame themselves for underestimating the speed of a particular target, but they don't go into detail on how that could happen.
The way I understand it, the skippers plot a ships position and a point ahead of it, and time using the stopwatch the time it takes the target to make it to that point. There are conversion charts for time/distance/speed.

At least, I think
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Old 04-17-08, 01:04 PM   #3
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Counting prop revolutions on the sonar, visual estimation, and plotting distance druing a known time (from radar, visual, sonar).

Real skippers had the added dimension of frequent zig zags along a base course and speed changes that for the most part we don't have to deal with.
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Old 04-17-08, 01:27 PM   #4
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Don't forget that real skippers also used Automatic Targeting! :p
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Old 04-17-08, 01:28 PM   #5
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Quote:
Originally Posted by Raptor1
Don't forget that real skippers also used Automatic Targeting! :p
HEY! Some of us would've needed it
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Old 04-17-08, 02:39 PM   #6
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I find this method very usefull
http://forums.ubi.com/eve/forums/a/t...5/m/1091073255
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Old 04-17-08, 03:03 PM   #7
stillalearnin
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The whole time, they would be running a plot also, and you also use that to get a TMA(target motion analysis).
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Old 04-17-08, 03:47 PM   #8
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Quote:
Originally Posted by badaboom
I see that metric stuff and I get nauseous. The method is OK if you have correct ship lengths (how do you confirm that? Real ship lengths or game ship lengths? Are they different?)

I'd rather time for 3 minutes and measure the distance traveled in hundreds of yards to find knots. Then I'm not dependent on information which could well be wrong.

If you insist on using those metric excuses for measurements, find the distance traveled in 3 minutes 15 seconds. The number of hundred meters traveled is the speed in knots.
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Old 04-17-08, 06:17 PM   #9
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Quote:
Originally Posted by Rockin Robbins
Quote:
Originally Posted by badaboom
I see that metric stuff and I get nauseous. The method is OK if you have correct ship lengths (how do you confirm that? Real ship lengths or game ship lengths? Are they different?)

I'd rather time for 3 minutes and measure the distance traveled in hundreds of yards to find knots. Then I'm not dependent on information which could well be wrong.

If you insist on using those metric excuses for measurements, find the distance traveled in 3 minutes 15 seconds. The number of hundred meters traveled is the speed in knots.
Aah yes RR, but this is because you use map contact updates on, which gives instant hyper-accurate ranges to target with your specially developed infra-red laser rangefinder (although as we both know a proper in-game radar system with usable ranges would help)

For those of us who don't, and also spurn the use of the OOD bearing and range to target option in TMO (range to target 31,347 feet Sir!), plotting can be a real pain, especially if there are course changes, which happens some times. Plots took a lot of time and effort to get an accurate result.

Anyway, if you want to do the fixed wire method in feet, do as i do:

Large merchants = 500 feet
medium merchants = 400 feet
small merchants = 250 feet

divide by number of seconds.

1 knot = 1.7 f/s
2 knots = 3.4 f/s
3 knots = 5.1 f/s
4 knots = 6.8 f/s
5 knots = 8.5 f/s
6 knots = 10.2 f/s
7 knots = 11.9 f/s
8 knots = 13.6 f/s
9 knots = 15.3 f/s
10 knots = 17.0 f/s
11 knots = 18.7 f/s

I have that table above taped to the back of my desk lamp, as well as the metric version for playing SH3 .

I hope the imperial measurements de-nausify you RR

joe
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Old 04-17-08, 06:23 PM   #10
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Quote:
For those of us who don't, and also spurn the use of the OOD bearing and range to target option in TMO (range to target 31,347 feet Sir!)
Beleive me i wish i could fix that. It annoys me too. Its a hardcoded issue with the game, one of the metric conversions what was never fully implemented. Truthfully, its existiance feels more like a "hack" to me then a mod, but i figure its better then nothing.
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Old 04-17-08, 07:19 PM   #11
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Oh for sure, i understand

Truth be told, i still use it for getting bearing to target, and as i can't really mentally process distances of feet more than 100, the result in effect gives a realistic range of very far, far, not very far as far as I'm concerned. I just don't try and calculate more accurately than to the nearest 1000 yards.
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