SUBSIM Radio Room Forums



SUBSIM: The Web's #1 resource for all submarine & naval simulations since 1997

Go Back   SUBSIM Radio Room Forums > Silent Hunter 3 - 4 - 5 > Silent Hunter III
Forget password? Reset here

Reply
 
Thread Tools Display Modes
Old 09-23-06, 10:11 PM   #1
RedMenace
Chief
 
Join Date: Sep 2006
Posts: 319
Downloads: 5
Uploads: 0
Default How do I measure speed?

Is there anyway to accurately measure a target's speed without the use of the notebook? I hadn't found one yet.
RedMenace is offline   Reply With Quote
Old 09-23-06, 11:07 PM   #2
Grrbob25
Mate
 
Join Date: Sep 2006
Location: Chicago, IL
Posts: 52
Downloads: 0
Uploads: 0
Default

you can measure by the way the smoke from the stack is moving or if your good enough, by pure eye


but the average of all lone merchants is between 3-12knts
__________________
LOS LOS LOS! BOP BOP SHU BOP
Grrbob25 is offline   Reply With Quote
Old 09-23-06, 11:41 PM   #3
Dantenoc
Captain
 
Join Date: Jan 2006
Location: Ensenada, B.C., Mexico
Posts: 504
Downloads: 0
Uploads: 0
Default

...are you asking for real?!?!

There are many, many different options: from the basic 3:15 rule, to the use of nomographs, and there's even an elegant method of telling speed by sound from the hydrophones (allthough I don't think it still works in heavily modded games)

Try a look at this helpful start:
http://www.subsim.com/radioroom/showthread.php?t=96026
Dantenoc is offline   Reply With Quote
Old 09-25-06, 02:12 AM   #4
supposedtobeworking
XO
 
Join Date: Jul 2002
Posts: 436
Downloads: 59
Uploads: 0
Default

Well while were talking about speed--I use the 3:15 rule which can be found in Wazoo's tutorial if you're interested. It can be very effective in theory but I have found it difficult to get an entirely accurate speed reading myself. Occasionally the distance interval between one of my plots will be very different than most of the other intervals (difference of up to .5 or so km!), and the rest will not quite be the same (within .2 km). I guess this gets you close, but when I hear other people talk about this method it sounds like they can get dead on results...sometimes I wonder if I am doing something wrong (I'm just using the ranges from the Watch Officer precisely in sync with the stopwatch.). There is another method to determine speed by measuring the degrees between the fore and aft of the ship when at closer range, but it demands you be in a good 90 position and close etc. not ideal...Only other one I know of is by sonar which unfortunately doesn't work for me since I use GW.

Also---do you have Wazoos nomograph---look it up on the mod list page and get it! you can then measure speed in other intervals instead of 3:15 (like say 1 min.).

Last edited by supposedtobeworking; 09-26-06 at 12:20 AM.
supposedtobeworking is offline   Reply With Quote
Old 09-25-06, 02:37 AM   #5
Phylacista
Electrician's Mate
 
Join Date: Apr 2005
Location: Aachen, Germany
Posts: 133
Downloads: 0
Uploads: 0
Default

heres the direct link to wazoo's tdc manual:

http://www.paulwasserman.net/SHIII/
__________________

commissioned 01APR1941 - 1.Flotilla Brest - 110,000 GRT total - 84 days at sea

*click pic to see how the real U-556 fared*
Phylacista is offline   Reply With Quote
Old 09-26-06, 05:54 PM   #6
Skubber
Officer
 
Join Date: Sep 2005
Location: Rochester, NY, USA
Posts: 239
Downloads: 36
Uploads: 0
Default

I get "dead-on" results with the 3:15 rule. That is to say, the torpedoes go right were I aim them. (At least they do in calm seas .)

When I first started playing the game, I thought it was crazy-talk to hear other players say they could target a specific area of a ship. I was just trying to hit a ship!

I suppose it would be more correct from a simulation POV to judge the speed with the hydrophones?
__________________

"I wish to have no Connection with any Ship that does not Sail fast for I intend to go in harm's way."
- Captain John Paul Jones, 1778
Skubber is offline   Reply With Quote
Old 09-26-06, 08:01 PM   #7
bert8for3
Ace of the Deep
 
Join Date: Dec 2005
Location: Canada
Posts: 1,124
Downloads: 110
Uploads: 0
Default

Quote:
Originally Posted by supposedtobeworking
Well while were talking about speed--I use the 3:15 rule which can be found in Wazoo's tutorial if you're interested. It can be very effective in theory but I have found it difficult to get an entirely accurate speed reading myself. Occasionally the distance interval between one of my plots will be very different than most of the other intervals (difference of up to .5 or so km!), and the rest will not quite be the same (within .2 km). I guess this gets you close, but when I hear other people talk about this method it sounds like they can get dead on results...sometimes I wonder if I am doing something wrong (I'm just using the ranges from the Watch Officer precisely in sync with the stopwatch.).
I don't think you're doing anything wrong, I use the same method and as you say sometimes there's an interval which is out of line with the others. I just discard it as having messed up somehow and take another. You do get more accuracy if you do several intervals. I also find that I can be out with the measurement because it jumps by 100 metres at a time, so I generally measure until the cursor just turns to the reported distance, this seems to give more consistency.
bert8for3 is offline   Reply With Quote
Old 09-27-06, 09:25 AM   #8
Redwine
Sea Lord
 
Join Date: Jan 2002
Location: San Martin de los Andes, Neuquen, , Argentina.
Posts: 1,962
Downloads: 10
Uploads: 0
Default

Quote:
Originally Posted by RedMenace
Is there anyway to accurately measure a target's speed without the use of the notebook? I hadn't found one yet.
You can use the Cosin Theoreme to solve it.

If you know two sides of a triangle and the angle between them, with the Cosin Theoreme you can obtain the third side of the triangle, then if you take the time between the two ends of this side you can obtain the speed.

You can do it manually :

http://rotteufel.iespana.es/htdc_tut...ercise_006.htm

Or... you can use a Whiz Wheel, a round slider calculator to do it.
Redwine is offline   Reply With Quote
Old 09-28-06, 02:57 AM   #9
Payoff
Captain
 
Join Date: Mar 2005
Location: Nash Town, USA
Posts: 525
Downloads: 1
Uploads: 0
Default

*1. Identify contact. Note Length in rec manual.

*2. Time contact bow to stern with stop watch.

*3. Length divided by seconds = meters per second

*4. Divided by .514 = Knots
__________________
"Hit Shokaku class carrier with three out of six torpedos. Recieved 105 depth charges during three hour period. Heard four terrific explosions in the direction of target, two and one half hours after attack. Believe that baby sank!" Lieutenant Commander Herman Kossler USS Cavalla
Payoff is offline   Reply With Quote
Old 09-28-06, 05:49 AM   #10
Notewire
Soundman
 
Join Date: Aug 2006
Posts: 143
Downloads: 75
Uploads: 0
Default

This is a good thread, and gets to the meat of helping us improve as Kaluens.

Payoff, does that work regardless of range? It has been a long time since I studied geometry, but it seems that range would affect knots given the time from bow to stern.

I will say, that I am working on this one myself - as I had been using the 3:15 rule exclusively - but then I started playing with no map contacts - Yikes! Now the 3:15 rule is much harder - as it is difficult to guage the range perfectly. Also, with NYGM - the watch officer doesn't give you uber range estimations. Now I am working on a 6:30 rule, and dividing by two to get speed, but still the Fast 90 shots are very difficult.

Anybody got any good tips?
Notewire is offline   Reply With Quote
Old 09-28-06, 07:23 AM   #11
Laffertytig
Grey Wolf
 
Join Date: Feb 2003
Posts: 757
Downloads: 110
Uploads: 0
Default

im having the same problem, im almost tempted to to on the god's eye view to make it easier. how r u supposed to acurately mark targets on the map so u can do the 3.15 rule?
Laffertytig is offline   Reply With Quote
Old 09-28-06, 08:59 AM   #12
bert8for3
Ace of the Deep
 
Join Date: Dec 2005
Location: Canada
Posts: 1,124
Downloads: 110
Uploads: 0
Default

Quote:
Originally Posted by Notewire
... I had been using the 3:15 rule exclusively - but then I started playing with no map contacts - Yikes! Now the 3:15 rule is much harder - as it is difficult to guage the range perfectly. Also, with NYGM - the watch officer doesn't give you uber range estimations. ...
I've been trying to ignore the watch officer's range reports (GW so they show). The stadimeter is tough to get a good range a lot of the time. I've been getting better results I think by putting the vertical hashmark line in the scope/UZO on the target and then getting a read on the target's size in terms of # of hashmarks, i.e. 1 1/2, 2+ a bit etc. Sounds inacurrate, but I think you can eyeball it easier and more accurately this way, rather than trying to hover with the stadimeter. When I get my # of hashmarks, then I click the stadimeter tool on the hashmark measurement to get the range.
bert8for3 is offline   Reply With Quote
Old 09-28-06, 10:02 AM   #13
Reece
CINC Pacific Fleet
 
Reece's Avatar
 
Join Date: Sep 2003
Location: Down Under
Posts: 34,701
Downloads: 171
Uploads: 0
Default

You could try my Time-Distance-Speed chart that loads into the Nav map screen, very simple to use but requires a 1.5minute timer (stop watch etc). Just download my "Mini Mods", readme doc supplied.
Cheers.
Edit: PS. rename the downloaded file from hyperupload to "Minimods.rar".
__________________

Sub captains go down with their ship!

Last edited by Reece; 09-28-06 at 10:04 AM.
Reece is offline   Reply With Quote
Old 09-28-06, 07:53 AM   #14
flakmonkey
Grey Wolf
 
Join Date: Jul 2006
Location: Staffordshire, Uk
Posts: 944
Downloads: 78
Uploads: 0


Default

i find the easiest way to measure speed is to simply count the rpm of the ships screws on the hydrophone, works perfectly every time for lone ships or very small convoys (sound is much too confusing in a large convoy though).
theres a great tutorial for this available in the downloads section of subsim (sound trainer mod)

as someone already mentioned some mods may make this not work if they replace the ships engine sounds.
flakmonkey is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 06:54 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright © 1995- 2025 Subsim®
"Subsim" is a registered trademark, all rights reserved.