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caspofungin
08-11-05, 01:09 AM
estimating speed w/ the realistic tracking mod is my achille's heel. what methods do players out there use? the default timer in the uzo/periscope while still? matching course and speed of target? or plotting on chart then measuring distance/time?

Knotical
08-11-05, 01:54 AM
Here is a similar thread posted a while ago you can check out:
http://www.subsim.com/phpBB/viewtopic.php?t=41143

There are many methods you can use to plot the target speed manually using map updates and time. Chart plotting / distance time as you say is probably the most realistic and easiest. Many of the TDC tutorials you can find on Subsim and elsewhere go over different methods. I can send you the spread sheet I use (see link above) if you want. If someone would like to post it to a website that is fine also.

P_Funk
08-11-05, 03:28 AM
hate to belittle you buuuut I think there's a simpler way to do it. Just look at Wazoo's tutorials: http://www.paulwasserman.net/SHIII/#Step%205:%20Get%20The%20Target%20Speed%20From%20Y our%20Observations%20(DS)

If you make markings every 3 minutes and 15 seconds then the distance between in the two equals the speed ie. 300meters covered in 3 min. 15 secs. would be equal to 3 knots. Read his stuff. It's cool.

SmokinTep
08-11-05, 06:43 AM
That's what I use.

caspofungin
08-11-05, 11:25 AM
Yeah, that's what I was using back when there were icons on the chart display -- it seems to be a little harder now there are none! Tried plotting range/bearing, but can never get it to be very accurate -- it doesn't take much error between plotting 2 positions for it to add up to a knot or 2 of speed difference.

Halifax40
08-11-05, 07:19 PM
Hmmm, I find this very interesting as I don't see too many people actually using the hydrophone to calculate speed. The hydrophone and counting the revolutions is probably the most accurate approach in my opinion. I use the 3.15m rule as well as double checking with a nomograph, and then triple checking with the hydrophone. Sometimes, you can get accurate speed calculations using the hydrophone in 15 seconds or less, which is the method I use first, and then check that number with the other 2.

You definitely should check out the Sound Trainer Mod hosted here, on Subsim. It includes a single mission for its training purpose but I found that using the chart and reading the instructions was enough. I jumped right into the Naval Academy and did the Torpedo mission on training - and instantly got accurate speed readings. It also helps if you have a sense of rhythm. I was in the marching band and jazz bands way back in high chool and am still very heavily into music - so it's really easy for me. A 4 bladed prop will sound very much like a 4/4 measure. 1, 2, 3, 4, 1, 2, 3, 4. All you need to do is count how many times you hear the "1" beat (how many times the prop has made a complete revolution) in 15 seconds, and multiply that by 4 and you get how many RPMs. Then just use the chart included the Sound Trainer mod for the specific ship and ta-da.. you've got an accurate speed estimation.

caspofungin
08-11-05, 09:22 PM
v hard core -- certainly worth a try