Manual Targeting Tutorial for a Parallel Attack

[Otto Heinzmeir]

There are a number of good tutorials already available for tracking and Fast 90 attacks, so I thought I'd do one for a parallel attack.


This attack is shown during the daytime but is meant to take place at night. For the sake of the tutorial its easier to show the attack in daylight. The attack took place from 2000 meters. It could be done surfaced or submerged. During the dark you can generally approach a convoy from the flank and get within 2000m without being detected while on the surface.

The advantage of attacking parallel while surfaced is you can turn 45 degrees away from the convoy and move ahead at standard as soon as you fire. Setting your torpedoes at slow speed will give you about a 2 minute and 20 second head start before the escorts are even aware of you. Once the torps hit, you can submerge and go to silent running. So by the time the torps hit your about 2700m away from the edge of the convoy and moving away from it. In real life most torpedo attacks took place from 1500m or more.

This tutorial is laid out so the descriptions are for the photo just above the text. Since there are already a number of excellent plotting and interception tutorials, I mainly concentrated on how to easily determine the AOB angle and how to set up the TDC manually.



Step 1: Locate a target and approach to a near parallel course. Ideally at night while surfaced for a faster escape. In this tutorial I am using my Watch Officer to get updates for the range and bearing to target.



Step 2: Identify the target and notice the draft. We will be using magnetic settings on tubes 1 and 2. So note the draft of 9.2m and since the sea is calm we will set the torpedoes to run at 9.5m. May as will write this number down for reference later.



Step 3: There is more going on here than the picture shows. First you start the stop watch, Since I am on the surface and using my UZO I started the watch in that screen then quickly switch to the nav map screen and ask the Watch Officer(WO) for an update. Then I set the Time Compression to 0 to pause the game. In real life there would be a team of us doing this but in game you have to do it all, so it helps to pause to give you time to zoom the vav map in close. Note The WO reports the ship at 1800m at a bearing of 273 degrees. I draw this angle starting from my sub's heading of 000 out to my portside. So 273 degrees is 360-273= 87 degrees portside. Don't laugh but sometimes I use my calculator for this. It may be easier to see your heading if your moving to a waypoint. I don't like to use waypoints close to targets in case I need to change course or hit reverse.



Step4: Now using the ruler draw a line 1.8 in length to represent the 1800m to target. This line goes from your sub along the angle you drew to the target in the previous step.



Step 6: At 3 minutes 15 seconds (3:15) you repeat the above procedure of getting a WO update, drawing the angle to target and a line for the targets range. In the example above I had already done a plot at 3:15, then 6:30 and now again at 9:45 since I started the stop watch.



Step 7: Drawing a line for the range to target for the 9:45 plot. Note that the range is now 2000 instead of 1800 when I first began. This indicates that I am not quite parallel to the target but going away slightly. Not a problem.



Step 8: We now have three timed plots. There are 4 lines because the first line was the position of the ship when we started the timed plots. Each of the 3 plots were taken 3:15 minutes apart. Notice that one of the plots is off quite a bit. I had waited too long as I was busy taking screen shots for this tutorial. What this step shows is I am measuring the distance that the ship traveled during the 9:45 minutes I plotted it. To determine speed. You multiply the distance shown on the ruler by 10 for a 3:15 minute measurement. But its best to use at least 3 plots for greater accuracy. So since I have three plots each at 3:15 minute intervals I have to divide my result by 3. The ruler measures the distance traveled as 0.7 multiplied by 10 equals 7 divided by 3 equals 2.3kts. The speed of the target is 2.3 knots. Write this down.



Step 9: I connected the 4 locations of the target to show its course or track. The track is shown in red to better see it. Note it doesn't touch all the plot points I made. It is the best average of the 4 plot points. I don't usually add in those marks that read mark 1 and mark 2 but I did that for this tutorial. Mark 1 is the current target location and mark 2 is my sub location.



Step 10: I now can draw the angle along the targets track to the target and then to my sub. This is the AOB angle. In this example its 116 degrees Starboard. In the TDC Starboard is the green side while port is the red side. Write down AOB=116



Step 11: Very important! Point the UZO if doing a surface attack, or the attack periscope if submerged at the center of the target.



Step 11: Go to the TDC screen and turn on the TDC by setting the switch shown by the arrow to the right.



Step12: Entering the data manually into the TDC. You should have everything written down so you can do this quickly in about 20-25 seconds. Since you are near a parallel course and near the same speed as the target. The TDC data will not be out of date as fast as if you and the target were traveling in different directions.

You can ignore the dial at the bottom left. This is entered automatically when you have the UZO pointed at the target as in the above step. The dial labeled 1 is to set the range and it is shown set to 2000 meters, the current range to the target. Dial labeled number 2 is to set the AOB. The AOB was 116 starboard. In the photo its actually set to about 106. Note that each large hash mark is 10 degrees and each small hash is 5 degrees. Its not possible to set it at say 116 or 117 so just put it as close as you can without wasting time.

The dial that I labeled 3 is to set the speed. Again as close to 2.3 kts as you can do quickly.

I am firing torpedoes from tubes 1 and 2. For each torpedo I first click on the tube in green and then set the depth, in this case at 9.5 as I mentioned earlier. This is set using the dial labeled as 4. The magnetic detonation is selected by the switch numbered 5. The speed is selected by the switch labeled 6. My TDC is in German so the L means slow in my case.

AOB is important but speed is probably the most critical component. The more plots you can do the better to get the most accurate indication of target speed.



Step 13: EXTREMELY IMPORTANT. You need to click the on/off switch back to the left or else none of your settings will be entered and you will waste your torpedoes.



Step 14a: Again IMPORTANT: After selecting tube 1 hit, the Q key to open the torpedo doors or your firing will be delayed by 2 seconds, probably enough to miss altogether. So select tube, open tube door. Place the UZO crosshairs where you want the torpedo to hit. Press fire.

Another IMPORTANT REMINDER. Note the TDC angle in between the 4 dials pictured. It reads 268. Subtracted from 360 means that this is a -92 degree TDC angle. Early in the war, a +/- 90 degree TDC angle is the max you should use. Later on you can use a +/- 130 dgree TDC angle.

Technically I should have adjusted my position to make this TDC angle smaller. The easiest way would be to drop back from the target a bit. Simply slow down for a time and let the target get on your 280 bearing instead of at 269.



Step 14b: Same as above only with Tube 2. Aim at a different spot to insure that 2 separete compartments are flooded.



Step 15: During an actual attack. Here is where you turn maybe 30 degrees to starboard and standard. Not full or flank. At full or flank you may give away your position early. Standard in a type VIIB will do 9 knots easy. When the torps hit just do a normal dive and go to 2 knots at silent running.



Note how far off the sub is.



First torp hits about 2 minutes 25 seconds after firing



Second torp hits!




Because they were magnetics all the damage is under the keel.

If you quote this tutorial, please remove the pics first, as it is quite images intensive and may bog down slower internet connections. Thanks!

[Otto Heinzmeir]

One last pic of the end result! Since you probably won't see the ship sinking if your moving away to avoid escorts. You can confirm the results by listening on your hydrophone.

[irish1958]

Very nice:
"Keep up the good work"

[Otto Heinzmeir]

Thanks, its all updated and I hope I caught all the typos.

I'd like to point out that this method of determining AOB angle is not limited to Parallel attacks.
Parallel course and matching speed to targets are preferred but not necessary. The advantage of a parallel attack at matched speed is that the AOB angle remains fairly constant allowing you more time to enter it into the TDC. So its a good way to start learning manual firing.

If need be, I may expand this tutorial to demonstrate the same methods used above but at a different angle of approach.

[Otto Heinzmeir]

Thanks, I enjoyed doing it.

Excuse these crude diagrams, did them really fast. Just wanted to show one of the advantages of doing a near parallel attack versus a more angled approach. These diagrams are to show what the actual target size would be like for the running torpedo fired from the subs from two different approaches. Notice from the parallel attack the actual target size is nearly the entire broadside of the ship while in the 2nd attack run, the actual target size is noticeably smaller. It's not an optical allusion but could be measured.

This was a historical type attack used in real life. If you also match the speed of the target, it is a way of double checking your plotted speed as well.

[Otto Heinzmeir]

I haven't written any others but there are some good ones out there. Wazoo's manual for one and a thread titled 'The Hunt" The fast 90 is probably the best way to start to learn manual. I did this tutorial in the navy tutorial because in my mission I was constantly in 15MPS winds.

Its best to start in the navy tutorial and pick a ship that doesn't turn. The C2 or medium cargo that is just off to your left when the torpedo tutorial loads is perfect. Turn your duds off before you start and make sure your external camera is on. Then get lined up and just plot the ship for 15 minutes and practice setting the TDC manual.

Perfect TDC settings mean zilch if your off on the targets speed by 1 knot. In my example the ship was only doing 2.3 kts but if it was doing 15kts the results would be the same as long as I estimated its speed correctly. So plotting is the real key.

Check out this link, it was a big help to me.

http://www.subsim.com/radioroom/show...highlight=hunt

[Pisces]

Perfect tutorial!!! I can't think of anything to add or do different.

[Threesixtyci]

Any specific reason why you fire one torp at a time instead of switching to S mode?

[Otto Heinzmeir]

Originally Posted by Threesixtyci

Any specific reason why you fire one torp at a time instead of switching to S mode?

A couple reasons. One is it just got to be a habit with me because I first learned the fast 90 method and fired from 500m. From that range in stock SH3 there was a good chance of sinking a ship with 1 torpedo. So I got in the habit of firing just 1 torp and seeing where it hit and with what effect. Being I was so close doing a fast 90 (the torp running time was like 22 seconds) I had plenty of time to fire a second if necessary. (note I think the ships in GWX don't go down as easy) So anything over 8 tons and and just fired 2 right away but still do it seperately.

None of that would apply though in this situation, from 2000m. But I still don't like salvos because none of the torpedoes go where you aim the crosshairs. Where you point the crosshair is the center of the salvo and then each torpedo goes a certain number of degrees off that center depending on what you choose for the spread.

I always aim one torp at the stack. Actually in the example above I was a bit in front of the stack because I was pre-occupied with making screen shots. If you have enough time to do 3 to 5 plots of the target you can get enough accuracy to to aim one at the stack and one in between center and bow.

If I was firing 4 torpedoes then I probably use a salvo with a 2 degree spread from 3500m, provided I ever get weather in game where I can see that far again.