Advanced TDC School: Multiple target attack

[ICBM]

Attention class!

I want to spice things up a little.. I'm getting tired with my current tactics, e.g often 'going Rambo' on a convoy. (racing submerged in between the ships abusing the dumb DD pathfinding AI, giving a damn about noise)

I want to atack at least 4 ships wich are not necessary in the same row.....SIMULTANIOUSLY! No 'ship-by-ship & Fire' notebook TDC but calculate most data beforehand and fire all 4+ torps seconds after each other on 4+ different ships.
Oh btw, I also want the targets to be hit as close after each other as possible to have dead accurate midships explosions. :huh:

Allready getting a headache? :)
I allready can atack 2 ships simultaniously using the fast 90 method but things are getting complicated when trying to calculate the desired torp firing order and distance for torps 3 & 4 (heck even 5 and 6 if you are insane enough).

Like this:
Here I've allready taken up an accurate perpendiculair postition in relation to the convoy, waiting for target #1(Lib) to cross my pre set bearing:
As you can see I've setup the atack in such a way that all 4 targets get hit as close to each other as possible, again to have super accurate midship detonations. Also, the distance to the target course line is 800m to minimize the gyro angle as much as possible. (can't be much further, or you will have collumn overlap)

http://home.hetnet.nl/~wouter-himself/SH3/FiringSolution1.jpg
Now comes the tricky part, the 2 dirrerent shipping collums are overlapping each other so to combat that you'd have to open fire before they start obstructing my line of fire, wich result in (perhaps to) high gyro angles.. Also, the torps need to hit there targets very soon after each other before the ships have a change of evading.
The results from this atack was disapointing, I misjudged the distance for torp 1, so torps 2,3 and 4 where still having a long way to go when #1 detonated. The remaining targets manged to evade my torps. Damn..if they hadn't evaded I would have hit hem all!

****************

Another one:
Is this situation I've taken up a position right in the middle of the 2 shipping collumn (liminating overlapping rows) to put the rear tubes into action, firing at 5 targets at once. The torp firing order is again set up in such a way that all targes get hit soon after another.

http://home.hetnet.nl/~wouter-himself/SH3/FiringSolution2.jpg
The problem with this method is that you will have high gyro angles since the distance is only 400m on each end, and you have to fire lead shots (traveling time) at the collumn leaders.
The result from this was a 2 kill, dunno why the remaning torps missed, probably to high gyro angles.

So far I've only managed to hit 2 ships at once, still looking for the perfect solution..
(ofcourse, every plan depends on what ships are present in the convoy, T2,T3,Trooptrans and libery gargo's have my attention)

Any thoughts on this, or even succesfull 4+ kills stories?

[Serverdaemon]

Any thoughts on this, or even succesfull 4+ kills stories?

Yeah...

You have WAAAAAY too much time on your hands.

:rotfl:

S

[Observer]

Easy. If the contact does not zig, once you have calculated contact course for one merchant in the convoy, they will all be on the same course. Remember 1 degree of relative bearing equals 1 degree of AOB. Point - shoot. Simple. Do not place TDC in manual except to update speed. As you swing the periscope, it will update the gyro angle.

In general here is my method for manual TDC:

1. Pick a lucky (or unlucky) merchant.
2. Take bearing and range to target, start timer and mark on nav plot.
3. Wait 3 min 15 sec then take second bearing and range to target and mark on nav plot.
4. Draw a line through the two marks. You now know convoy course.
5. Use the range tool to measure the distance between points. The number is the convoy speed (should check with radio message).
6. Enter convoy speed in TDC.
7. On the nav plot draw a line from ownship current position intersecting the convoy course at o degrees relative bearing (use a bearing overlay...it helps greatly). Use the angle tool to measure angle on the bow at 0 degrees relative bearing. You now know AOB at 0 degrees relative bearing. Align the periscope to 0 degrees relative, clear the scratch pad and enter the AOB you calculated, then clear the scratchpad.

Done.

You now know the course, speed and AOB to every contact in the convoy. The only thing you need to determine is range for torpedo run time to target.

For overlapping targets look down the gyro angle to ensure the path is clear prior to shooting. As always shoot farther targets first and time shots to arrive at the same time.

[Observer]

One addendum. Use the WO to post the solution on the attack plot. Pick your far target first, then repeat for the near target. The only thing you need to update is range and the intended tube (if using a mix of steam or electric torpedoes). The difference in time is how long after the first shot to shoot the second for arrival at the same time.

Another method is to assume a column separation of 700 meters, then measure distance to the track along the gyro angle. A 30 kn torpedo will travel 930 meters in 1 min, therefore you should shoot the near target about 40 seconds after the first shot to get arrival at the same time.

The optimal setup for this is long range shots. I would not attempt 5 (or even 6) simultaneous shots when inside 600 meters because of the high gyro angle. The fast 90 method is superior in these situations. Time is not a factor here because the contact cannot maneuver fast enough to avoid the shot, and shooting with a high gyro angle leads to a higher probability miss due to weapon turn time.

[Walsung]

I agree with the first post of Observer i could add some tactics suggestions :

For the first attack :
- instead of keeping your sub on a perfect 90° from the path of the convoy, try to present yourself on a 80°. This will considerably lower your gyro angle, and anyway you can't shoot at a 0 bearing because the targets overlap.

- try to get closer. 450-500m instead of 800 will do a big difference and will reduce the timing between the impacts but most important you're greatly increasing your accuracy on some tricky fire solutions like T2. At night it will be easier not getting spotted, but anyway, when everything is set for you, just lower your periscope, follow on hydrophones the bearing of the closest ship, when it reaches a bearing you choose that gives you a close distance but enough time to prepare to fire, raise it and start aiming. This will greatly reduce the chances of detection before the launching.

- Prepare a plan of fire : assign a torpedo tube for each target and prepare it to be fired on that specific target you choose for that tube. If the angle of fire is not between 330-30° you don't want to go for impact anyway. For example on your drawing, T1 and T2 Must be treated with magnetic torps. So set all the corrects depth for magnetics torps on your sequence of fire in advance, you don't have time to do it between each shot, or you'll be too late. Then just do your planned sequence : for example torp 1 on T2 torp 2 on LIb, torp 3 on T1, torp 4 on T3.

- I suppose you know that, but lower immediatly your periscope after last launching. Sometimes you get spotted not before firing but when you're waiting to see you're firework. Just raise it some seconds before the impact if you really want to take a look.

Normally it works :)

[ICBM]

Thx for the advice, this may come in handy now that I am aproaching 1944..

When Elite DD's with Hedgehogs are guarding the convoy I REALLY want to be at 150m after the atack ASAP..

[Walsung]

For escape, if you estimate that you can't have a clean escape fast enough, you start to get pinged for example, or DDs are coming to you on a very bad angle, (you're presenting to them a noisy aspect), try to use the convoy to loose them. Convoy can be your allied. It makes a lot of noise and DDs are forced to constantly manoeuver to avoid the other ships. The confusion you created and the evasive manoeuvers of the merchants will increase the difficulty for the DD's to have a clean path to you. Hydrophones are very usefull once again in this situation.

[Curval]

Any thoughts on this, or even succesfull 4+ kills stories?

Yeah...

You have WAAAAAY too much time on your hands.

:rotfl:

S

I read a few lines then saw the diagrams....suddenly the voice of Charlie Brown's school teacher started in my head:

waaoo owwooaa ooaaooo whhhaaaa

:lol:

[Frederf]

In SH4 the other day I attacked a 3x2 convoy. 800yd spacing lateral, 1000yd spacing longitudinal. I fired them in the following order with 29kt electric torpedos.

Far Advance
Far Trail
Medium Advance
Medium Trail
Near Advance
Near Trail

I figured what time it takes for a 29 kt torpedo to cross 800 to 850 yards between ships and tried to fire along those times. The torps heading for the front ships were going to take a little longer so I shot them first.

It was done in such a way that row wasn't aligned just yet so I had room to shoot in front of their bows in order to miss the near ships to hit the far. The ones destined for the middle ships had the benefit of being a deeper depth for bigger ships so that wasn't too bad.

I used a torpedo track angle of about 15 degrees I think so that any miss would have a chance of hitting another ship in the row. This only worked for the first row, the angle on the rear row made it a "this ship of nothing" affair. The convoy was doing 9 knots and the torps 29 so that's 17 degrees to run a torp through the imaginary center of a whole row. The 15 instead of 17 was because when ships evade they tend to lag behind so a lagging shot has a better chance to hit.

The first row passed by about 500m and the second is about 500m from passing my bow. The formation is 1600yd wide and I'm 800 from the near column so I'm using about all of the 4000yd range on these babies (remember the long shots are going slanty so travel longer than 1600+800).

Fire one, fire two. Has that been about 25 seconds? Yeah I think so. More like 30.
Fire three, fire four. That took too long. I hope they don't impact early.
Fire five, fire six. Ok that's everything. Hard to port, depth 400.

External camera.

Approximatelya minute after the last launch the first should hit. .... Torpedo impact!
Torpedo impact!
Torpedo impact!
Torpedo impact!
Torpedo impact! All within about 8 seconds of each other. That's one for the history books.

Three broke up immediately. I've never had such luck with single torps. It usually takes 2-3 to sink anything bigger than a DD. Four and five sunk some 5 and 20 minutes later. The lucky one in the far row got away. The escorts hounded me for ages sending me back to port early with some large holes on my deck. I swear they have golden ears.

[looney]

To bad the pictures aren't around anymore. I'm very interested!