1. In an absolute sense, you making a good deal of noise because...
2. the escorts are very good at picking you up.

Once I encountered a convoy had to make a quick turn and went ahead 2/3, submerged, and the escorts were about 2-3 km away and the detect-o-meter changed from green to red for about 3 seconds and they came directly looking for me. From what I hear, and know from experience, is that the DD's in GWX are tough.
I'm not sure about variables but I think you cant make too much noise even around large convoys where the SNR is loud without counterdetection.

edit: I dont think the km visibility affects their dectability. Unless they suddenly appear right on top of you, in which case this would be a timecompression problem. These are the only times that I know of when I've seen the uboat detector turn red with out warning.

Reminds me a bit of some of the stock missions/campaign in Sub Command. A booming voice announces over your speakers, "You've been counter detected!"

Yes, it does seem that time duration plays no role in their listening. The other day, I was practicing and I accidently hit "3" instead of "F3". Of course, I realized my mistake and fixed it almost instantly.

No matter. An escort came to my exact position and started pinging.

I havent played DW or SC recently, but detection in sh3 acts almost in the same way. Make sure you crew is up to speed and you'll do much better, especially with detection/counter-detection.

I cant answer for the actual values in this or the AI algorithim, but their pretty damn good. Usually the first DC attack is the kill shot. After that too much of a noisy environment and they loose a bit. Once you get going after the 1st DC attack keep up the stealth. YOu have to manually use the sonar if you want to be ontop of just about everything.
edit: unless theyre pinging you, then no holds barred clear datum as fast as you can.

There are two ideal ranges:
1500-3000 meters for targeting multiple ships, with TII or TIII. Usually distance between ships in a convoy is about 500 meters, a TII or TIII runs 927 meters per minute, which means it takes about 30 seconds to run 500 meters.
If you hit one ship in a convoy, all ships will zig-zag, making it harder to hit.
My way of attack: aim at the first target 2500 meters from you, launch torpedo and aim at second one which is 2000 meters from you, launch the second torpede on the second target when the first torpedo had been launched 30 seconds. Then two targets shall be hit almostly at the same time.
In GWX many ships still have weak points, so you are lucky enough, you can destory 4 ships in a single attack:damn:

The other ideal range is 300-500 meters, keep yourself in the middle of the convoy and aim at the weak points, one torpedo kills on ship:rotfl:

Weak points:
The most valuable merchant is LARGE MERCHANT, weak point is between the first mask and the bridge.
C2/C3 and cargos smaller than them: one torpedo is enough to sink them if you hit under the last mask.

Excellent read, folks
Detection threshold is the key, then your attack

Well,I don't see any sense of getting inside a large convoy.You see,if you are within a convoy,and suddenly get compromised,a real mess is starting around.
All ships start zig zagging,one ship closes the line of fire into other ship and vice versa.In addition,you have got a pretty fast escorts inbound on your position.
And everything usually ends quite uselessly,all ships escape,or do such zig zaggs that you're simply unable to target them,escorts arrive at your position or force you to crash dive and turn 2 knot speed there.And all hunting ends at this point.

The real moment of truth is not getting yourself inside the convoy,but when you do a correct,predictable convoy interception course plotting.The ideal convoy attack position is not within,but outside a convoy,and such position maybe described by the following:

1.You start getting reports from Sonar Man,saying:"Merchant Closing"."Closing" means that you are already on correct course of interception.

2.There maybe visual contacts from observation officers on deck,saying "Ship Spotted".After that you may submerge to periscope depth or even deeper and get correct bearings as well as speed,distances of the rest ships inside a convoy.

3.At this point,you may rise a persicope and start planning an initial convoy torpedo attack.You are master of your own,you may do everything calm,without rushing or looking around for inbound escorts.You pick up valuable targets,set correct gyro angles,set torpedo depthes and speeds (for TI-G7A torpedo) and perform and sniper,marksman launch.And if you do everyting correctly,you may sink 3 or even more bigger ships.Moreover,it very important that you are unspotted at your attack position,you crash dive,evade escorts and may repeat an attack within next hours.Actually,you may destroy the whole convoy within several days.I think such precise strikes are the exactly those,a Type IX U-Boat was designed for- to follow a convoy and strike night after night.But each attack must be precise and successfull,as well as effective regarding to sunk ships quantity.And for all that,you need a favourable attack position,which is to my mind,always - outside a convoy.

That's just my personal opinion,you may disagree with.Good Hunting,Kaleuns!:D :up:

Genghis Khan,

Are you talking about distant submerged night attacks on convoys? If so, how do you do it, since it generally looks pitch black to me at night and I don't know how could target anything. Thanks.

MarkShot,I must admit,I do use targeting help,just rotate the periscope and search for target marks,if they are closing on my position,and valuable at the same time,I prepare a launch.But I think,that normal visibility is needed in any range of attack.

I always seem to find the convoys when I'm low on fuel, so time is never on my side.

Targetting marks - you mean you are using the auto target option?

Myself, I am using the Weapons Officer. I suppose then, similar to you if I scanned the scope across the darkness, I could watch the contact type field change on the notebook. Then, simply lock it and shoot.

Thanks for clearing that up.

MarkShot,you are right-that's auto targeting.And,I must say,I perform all attacks on my own,I mean- pick up valuable targets,set gyro angles.Target marks are those triangles,that change their colour according to gyro angle.I don't use my WO.

Okay, so you use the triangle to spot a ship.

Then, how do you ID, range it, AOB, and get speed in the darkness? Sorry, I am still confused.

Thanks.

MarkShot,there is a notebook in Right-Upper corner of UZO/attack periscope screen...all info regarding targeted ship is calculated and shown there.Auto Targeting,as I said before.Just point to a ship and all info will be shown there automatically.

Doesn't that take some of the fun away? The most satisfying thing for me has always been to get it in my sights, calculate the range/aob/speed and get a hit from 2500m (preferably with no duds).

I have spent the last couple of days practicing submerged inside (within the formation) attacks of convoys.

I just started with outside attacks. I can definite see the advantages of long range outside attacks:

(1) There usually appears to be a lead escort which you must clear to get in the formation. On the outside, the lead escort will naturally miss you. Of course, there are escorts coming up the flanks, but, at least, you are guaranteed to get a shot.

(2) Situational awareness is much better with the entire convoy in a narrow field of view as opposed to all around you. As was stated, you get a much better chance to pick and choose.

(3) I think as also stated a good displacement off to the flank negates your slow speed allowing you to adjust the angular bearing you need to keep your torpedo gyros in parameters.

(4) Shooting down a row is much easier to set up which increases your odds of hitting something.

I have to say as soon as I ran the first profile, I realized how much superior it is to attacking from the inside. In AOD, what made it so attractive is that if you made it past the screen, then you were as far as you could be from any escorts and stood a very good chance of stealthly evading out the back of the convoy.

It is a real pity that random zig-zag behavior was not built into the base course behavior of the convoy AI. That would have made setting up the attack so much more interesting:

(1) It would have taken a lot more work to establish a base course for convoy.

(2) Even though a base course was established, it would have been impossible to know exactly where to position your sub way in advance (I drew lanes of 1km out to 4km from the base course and just came in on the opposing course down the 4km line, then turned into the convoy). Thus, an attack would have require more than some map work, pre-positioning, rotation, and shoot. You would have been required to make an attack approach to adjust for variations upon the base course.

(3) Finally, despite a nice setup, a zig could blow an attack leaving all targets too far, or too close, or a zig could put one or more escorts coming straight over you. I've had all of this happen to me in AOD.