Target speed calculation made easy

[RedHammer]

rgr. I think I found a way to determine bearing,
First I find the mogami in the recognition manual, input it to the tdc.
then I went to the map, and drawed a line from the Mogami`s stern to maybe 100 meters in front of it. Then I took the Compass, and clicked in 30 yards away from the end of the "100 yard" line, which the Mogami will reach within x amount of time, and i expanded it, and then made it so it pointed against my sub. Then I took the protractor at the exact end of the 100 yard line and to the 30 yard away from end. and then to my sub, I had a value of about 63 degrees to his Starboard. Which is then, AOB, then I hurried up and got range and speed into the TDC.

I repeated the above AoB trick I just did, and thus, I managed to calculate AoB within 30 seconds. Which was about 3 degrees in 30 seconds, give or take.

Finally! All 4 torpedoes hits at exact same place on the Cruiser, and he goes down quick!


Thanks alot for the solution

S!

RH

[RedHammer]

uhm nevermind, that method i just mentioned didnt work, i got too much of a bearing change for the speed to be correct..

So what you are saying, is that I have to check the bearing change by Visual Eyesight? How will I be able to see, with my own eyes, thru a periscope, at 1100 yards, if he changes his course by 3 degrees?

Getting frustrated again.. Ubi.. please fix the auto bearing finder..


S!

RH

[tedhealy]

Thank you much for the table

[Nightmare]

I'm wanting to use the plot over time, so I'm making my drawings on the nav map. What's the formula to figure out speed using this method? I'm also using imperial mesurments.

[lms_oid]

Originally Posted by Nightmare

I'm wanting to use the plot over time, so I'm making my drawings on the nav map. What's the formula to figure out speed using this method? I'm also using imperial mesurments.

Say you have plotted a move of 0.6 nm in 3 minutes. You now know your target is making 0.6 nm each 3 minutes. Since there is 20 times 3 minutes in an hour, your target speed is (0.6 x 20) knots (since 1 knots = 1 nm per hour). So your target speed is 12 knots.

lms_oid

[Barkhorn1x]

Thanks for this - I took your table - and the methodolgy comments and made a nice reference sheet out of them.

[micky1up]

why not have the sonar report the rev count of the engine and have a TPK (tuns per knot) for each vessel ie a battle ship has a tpk of 8 and the rev count is 80 therefor the speed equals 10 kts

[W_clear]

Thank you much for the table

[RTKSpiff]

Nice table

To get the effect of AOB just divide your answer by sin(AOB), but then
you need a calculator

[Viktorbg]

Im using this V=L/T * 1.96
V=L/t*3600s"1hour"/1850m"1knot"
V=Speed
L=Ship lenght
T=Time of 1 ship lenght


with speeds below 4-2 the observation time is too much(~90 s) and above 35 knots the error tolerance is droping but the AOB dosen't mater at all.

I can't found warships lenghts anywhare, plz help

srr for my english

[Rykaird]

Originally Posted by lms_oid

Say you have plotted a move of 0.6 nm in 3 minutes. You now know your target is making 0.6 nm each 3 minutes. Since there is 20 times 3 minutes in an hour, your target speed is (0.6 x 20) knots (since 1 knots = 1 nm per hour). So your target speed is 12 knots.

lms_oid

Thanks very much for this simple explanation of how the equivalent to the old 3:14 rule works!

[Nightmare]

Originally Posted by lms_oid

Say you have plotted a move of 0.6 nm in 3 minutes. You now know your target is making 0.6 nm each 3 minutes. Since there is 20 times 3 minutes in an hour, your target speed is (0.6 x 20) knots (since 1 knots = 1 nm per hour). So your target speed is 12 knots.

Thanks you! This should help tonight when I practice a little more. I was using Neal's method of using roughly half the targets max speed with some minor tweaking.

Another thing I found is there is a button in the lower right corner of the position keeper (just to the right of the position keeper/torpedo settings switch). Once you take your range, AOB, and speed and enter them into the TDC, hitting that button will set the TDC to track. In theory, if you are accurate with those three things, the TDC will keep an accurate firing solution and update the torpedo gyro angles continually.

When I'm ready to fire I:
1) raise the scope
2) check if the generated bearing in the TDC matches (or close to it) the bearing from the scope.
3) check to see if the generated AOB in the TDC matches roughly with what I see in the scope.
4) take one last range and submit to TDC and see if the generated range was off.
5) If all those things check out, it's time to shoot!

[lms_oid]

Originally Posted by RedHammer

uhm nevermind, that method i just mentioned didnt work, i got too much of a bearing change for the speed to be correct..

So what you are saying, is that I have to check the bearing change by Visual Eyesight? How will I be able to see, with my own eyes, thru a periscope, at 1100 yards, if he changes his course by 3 degrees?

Getting frustrated again.. Ubi.. please fix the auto bearing finder..


S!

RH

I know what you did wrong and in fact I was doing it wrong to!

The time you spend entering the AOB and estimating the speed, the bearing changes! And the bearing is only updated in the TDC by the synchronisation button on the stadimeter (first tool of the 3)! Just before launching the torp with AOB and speed set, you should go to the stadimeter and send another time the infos to the TDC or the bearing information in the TDC will be false and you will fire behind the target!



On the video below, you can see that just after entering speed, I launch the first torpedo without re-updating the bearing in the TDC. And just after that I launch a second torpedo with bearing updated. The two torpedoes take very different route and the first one miss but not the second one!



lms_oid

EDIT :

Reading again your last post :

Originally Posted by RedHammer

How will I be able to see, with my own eyes, thru a periscope, at 1100 yards, if he changes his course by 3 degrees?

I realize that you don't know what is the bearing I talk about! There is no link at all with the course of the target! It's the number you can read at the top of the screen when using the periscope. You should be able to read that!

[Rykaird]

Originally Posted by lms_oid

I know what you did wrong and in fact I was doing it wrong to!

The time you spend entering the AOB and estimating the speed, the bearing changes! And the bearing is only updated in the TDC by the synchronisation button on the stadimeter (first tool of the 3)! Just before launching the torp with AOB and speed set, you should go to the stadimeter and send another time the infos to the TDC or the bearing information in the TDC will be false and you will fire behind the target!

On the video below, you can see that just after entering speed, I launch the first torpedo without re-updating the bearing in the TDC. And just after that I launch a second torpedo with bearing updated. The two torpedoes take very different route and the first one miss but not the second one!



lms_oid

Can you do me a favor and post the setting you are using in torp school? I always hit aft, in the same spot back by the airplanes.

I'm updating all my info in the instant before I fire:

AoB 70 starboard (as measured on the nav map)
Speed 9 knots
Distance 1010 yards (from the stadimeter)

I'm firing at approx bearing of 348 (giving me near zero gyro angle). Bow cap is open, torp set to fast.

The only way I can hit him dead center is to set the speed to 11 knots, which is faster than what I'm measuring.

Thanks!

[RedHammer]

I will try as good as I can to explain again: The AOB does NOT update, UNLESS, I have a speed input. And even so, that speed input MUST be the ships actual speed. So I am back at start.

I`ve tryed many methods here but none of them seems to be working for me. If they work for others, great I have no choice but letting my future pleasures of sh4 into the hands of the devs. They gotta fix the Auto Speed determinator in the Chronometer. Or I can`t simply play this game.


S!

SK