View Full Version : How do you time a ship to get its speed?

06-23-2005, 05:46 AM
I can't work it out at all - it seems all hit and miss to me.

06-23-2005, 06:05 AM
You need two exact positions. Measure the time the ships spent travelling between those points, and the distance.

06-23-2005, 08:20 AM
Get an accurate start position

Time them for 6 minutes

get an accurate end position after 6 minutes

Measure the distance traveled. For simple example

Traveled 2400 meters in six minutes on a straight line. Drop the 2 ' 00's '

You get 24, divide in 1/2 . You get 12. The target was traveling 12 knots.

This also works the other way, for example you know the targets speed, but need to determine where he will intercept you.

Target speed is 5 knots. Double it to 10. Add the two " 00's " you get 1000. The target will travel 1000 meters in 6 minutes at 5 knots.

06-23-2005, 10:04 AM
The way I've been doing it with the god-eye map updating is to just draw a line with the ruler thru the updating target symbol on the map representing the targets course.

Then I draw another line intersecting slightly ahead of target. I use it as my starting line when bow crosses the line I jump to parascope or uzo and start stopwatch for 3 mins. I usually accel the time a bit so my wait is only like 15 secs and not a literal 3 mins.

At the end of 3 mins I jump back to nav map and mark bow position of ship. Then ruler measurement the starting line to mark. Typically a large cargo ship the length of the line is 0.6 or so. The .6 can be read as 6 knots.

The god-eye map is the biggest cheat in my opinion, but I hate using the stadometer, especially annoying when seas are rough and stabilzation is turned off.

I do all my calcs with the god eye map as the only cheat (allows me to have like 87-88% on realism so my reknown multiplier is still decent).

I had the 1.3 patch installed, now I have the 1.4b patch. I don't use any of the charting mods. The protracter allows me to figure AOB and setup 90‚? course intercepts and so forth.

I've actually found that I rather like using the nav waypts feature to tell my nav officer to follow a specified course that puts me at a 90‚? 1000m spot in my targets path. I can usually leave the TDC inputs set at 0 bearing, 1000m and I just have to pick AOB as 90‚? port or starboard. Then I use fast 90 or advanced fast 90 targeting methods.

I really wish there was a feature that allowed me to save multiple nav waypt courses. This would allow me to have a set of nav waypts for my planned course to a patrol zone but then I could flip it to use for my attack positioning if I wanted to. As it is now, I have to delete my nav waypts to patrol zone so I can use them for attack positioning. Some might say I'm cheating using navpts for my attack run but I like it.

06-23-2005, 10:19 AM
What I do is stop the boat. This gives you a more accurate speed in knots. I find that the average speed of the boats is 7-8 knots. At any rate, you can go to manual input using f6 for the torpedo control panel. Hit the manual button, move target speed dial to 7 knots or what you think it is. Now change the manual button back to weapons officer assist for the rest of the calculation. Like I said the average is 7-8 knots or in that area. If you get within 1000m to 400m you should be dead on with this speed of knots for the boats dialed in. Again, the slower you go while taking your speed with the stop watch the more accurate. Also let the stop watch work for about 3 minutes.

06-23-2005, 10:36 AM
Wazoo's tutorial says it's best to make 2 observations 3 minutes and 15 seconds apart.

http://www.paulwasserman.net/SHIII/#Step%204:%20Wait%20...ext%20Observation%20 (http://www.paulwasserman.net/SHIII/#Step%204:%20Wait%203%20Minutes%20Then%20Make%20Ne xt%20Observation%20)(DS)

Why? Because:

Luckily, we have taken our observations in 3 minute 15 second increments. This has a HUGE

benefit of being able to calculate the target‚‚ā¨ôs speed without having to make

complicated calculations on the fly.

Just select the ruler tool and draw a line connecting the two target points

you plotted during your two observations. The distance of your line

is a very close estimation of what the target‚‚ā¨ôs speed is in knots.

For example, if the length of the measurement is .3km (or 300m),

then the speed of the target is 3 knots. 500m is 5 knots, etc.

06-23-2005, 11:41 AM
Hmmm... 3min 15secs.

I'll give it a shot! I've been doing pretty well with 3mins but I do notice when I miss it tends to be slightly astern. Maybe this will improve my accuracy a bit. Not sure if too many of the merchants would change the reading with an extra 15 secs but I imagine it might help with faster targets. I haven't been too successful against destroyers but I kinda figured that was true to reality. Now maybe I have a better chance, thanks! I read that doc too! Wonder how I managed to overlook the 15secs?

06-23-2005, 11:45 AM
Anyone know if there's any talk of having the stopwatch as a tool available on the nav map?

06-23-2005, 11:45 AM
If you look at the logarithmic scale of the Nomograph mod, you'll see it's almost exact. The distance covered (in hundreds of meters) over a time of 3 minutes 15 seconds is almost exactly equal to the speed in knots. It's sufficiently accurate that I hit a target from over 2000 meters with a torpedo, firing blindly from a submerged position.

06-23-2005, 12:14 PM
The 6 minute rule works as well, is still accurate, and easy to do in your head if you don't have the nomograph mod.

06-23-2005, 12:34 PM
I don't want the mods...

Trying to avoid potential patch update issues.

The only mod I make (that I think I can't live witout) is remapping the keybindings so I'm not sporadicly launching torpedos into the atlantic when I'm trying to accel time.

06-23-2005, 12:37 PM
Originally posted by The_Third_Half:
The 6 minute rule works as well, is still accurate, and easy to do in your head if you don't have the nomograph mod.

Yeah, but it takes 6 mins. Is there any good reason to wait 6 instead of 3 (or 3:15)?

06-23-2005, 12:45 PM
Just the way i do it.

I can make very accurate intercept courses and such by mapping out the distance traveled in increments of said time, and plot my route accordingly. I end up on the map having a visual reference for where he will be at any given minute in relation to my boat.

I'm not saying YOU HAVE to, just saying it works, and it's pretty handing for plotting out a route on the map.

06-24-2005, 08:39 AM
Yeah, I can see where the wider spread would be more helpful for course plotting if you're not using the godeye nav map.

That does make some sense, I'll keep it in mind when I eventually try a 100% mission.

06-24-2005, 07:27 PM
Does anyone else find that you have to keep flipping between F3 and F6 to get all the details into the computer?
By the time I've got them all in after continually flipping, at least one of them is old data.

Am I doing this wrong, or do I jsust need to work on the memory?

06-24-2005, 07:29 PM
Oh, that was sarcasm by the way. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

06-24-2005, 07:58 PM
Logorithims, sliderules, compasses, dividers..etc.
I use good ole Mk 1 eyeball and estimation.
I estimate speed, distance (from scope calibration--mast to water line), trajectory to bow and with these er...mathematicals LOL I go for it ! 80% hit rate at 800-1000 metres range anyway.

Let em get in close enough and you dont need to work out all the science.
Get distance first though MOST important.
get as close as poss.

practise, practise and then practise !

Tagrget lined up Sir..........0 degrees gyro angle, 900metres slow speed Sir....Ok, cheers Mukka!...set torps for fast running 4 meters depth...set torps for magneto det just incase..........FIRE one..........FIRE two..........down scope..........ahead full..........left rudder 20 degrees..........rudder admidships..........upscope..........*BOOM......BO OM...KA-BOOOOOMMMMmmm*.........target atomised Sir *giggle*..........Surface...ahead standard....aye aye Kapitan...you star...**muwaahh...Kiss ! **....Get off ya soft git !!