Impossible to find subs?

[Lycon]

So I get contact, ofc its a sub, i get torps in the water message, i steer my DDs directly towards the torps at 10knts with radar/active sonar and spread them out a fair bit yet ive never seen a sub? like wtf am i doing wrong? I just started playing this game and so far its been boring as all hell with nothing but subs attacking and I just have to leave combat because it gets boring after 30 mins of ocean.... EDIT: and again lmao, 0 fun. I start battle instantly see the torps being launched super close, I dodge all torps and head straight towards the launch point at 10knts with active sonar and nothing? Like are you fking kidding me? also its a spread of 5 torps, I thought most subs had like 2 launchers front?

[Kraznova]

I suggest taking some time to watch some Youtube videos on how to do sub combat. In short, you need at least 2, and preferably 3 ships to prosecute well. 1-2 to go slow with active sonar, less than 9 knots most days, and one to "hunt".

Most subs had between 4-6 forward tubes during WW2.

[Lycon]

Początkowo opublikowane przez Kraznova:

I suggest taking some time to watch some Youtube videos on how to do sub combat. In short, you need at least 2, and preferably 3 ships to prosecute well. 1-2 to go slow with active sonar, less than 9 knots most days, and one to "hunt".

Most subs had between 4-6 forward tubes during WW2.

oh so its lower than 10 knts? i thought passive sonar was 10knts. ive had 3 ships spread out in a line next to each other. didnt have one at full speed to hunt though. so what does the hunter do? just full speed and active sonar?

[Crazed Possum]

Początkowo opublikowane przez Lycon:

So I get contact, ofc its a sub, i get torps in the water message, i steer my DDs directly towards the torps at 10knts with radar/active sonar and spread them out a fair bit yet ive never seen a sub? like wtf am i doing wrong? I just started playing this game and so far its been boring as all hell with nothing but subs attacking and I just have to leave combat because it gets boring after 30 mins of ocean.... EDIT: and again lmao, 0 fun. I start battle instantly see the torps being launched super close, I dodge all torps and head straight towards the launch point at 10knts with active sonar and nothing? Like are you ♥♥♥♥♥ kidding me? also its a spread of 5 torps, I thought most subs had like 2 launchers front?

Number one this is easier done with more than one destroyer that said both destroyers need to go to the area where the sub was and slow down to like six or seven knots once you pick up the sub one destroyer stays at the speed of the sub which is usually around 7 knots while the other one or possible two other destroyers make attack runs on it thus you'll always keep contact with the submarine.

[MizuYuuki]

Początkowo opublikowane przez Lycon:

Początkowo opublikowane przez Kraznova:

I suggest taking some time to watch some Youtube videos on how to do sub combat. In short, you need at least 2, and preferably 3 ships to prosecute well. 1-2 to go slow with active sonar, less than 9 knots most days, and one to "hunt".

Most subs had between 4-6 forward tubes during WW2.

oh so its lower than 10 knts? i thought passive sonar was 10knts. ive had 3 ships spread out in a line next to each other. didnt have one at full speed to hunt though. so what does the hunter do? just full speed and active sonar?

You have to use active sonar, and that works at 15 knots or less. At first, send the DDs at high speed toward the estimated location of the sub. At about half the estimated distance, slow down to 15 knots or less and turn on active sonar on all of the DDs. You don't want to overshoot the sub because there is no sonar detection to the rear of the DD. In the options menu of the game, there is a sonar range multiplier. The default 1x range is about 1600 yds for a sub at a depth of 340 feet in sea state 2. IJN subs can go that deep. For higher sea states or the sub passing through a thermal layer, the sub is more difficult to detect. Once the sub is detected, use one DD to shadow the sub because the DD that makes the depth charge attack will lose contact as it passes over the sub. I find that depth charging along the long axis of the sub with 2x and 5 sec interval depth charge settings works well. I usually attack the sub from the rear with the DD moving at 10 to 12 knots; slower if the sub is stationary. If the sub is moving at high speed avoid dropping the depth charges too soon because it takes time for them to reach the depth of the sub.

[Luetjens]

You also have to take the weather and sea state into account, with bad weather or rough sea the ambient noise will be very high that it's very hard to pinpoint the sub unless you are directly above it or extremely close to it. Also the existence of a thermal layer will tend to keep the sound travelling between the layer and the surface, masking the sub hiding below layer depth. (you will have a better idea how it works if you have played cold waters, which is focused on ASW warfare) However, if a layer exists and the surface duct is very strong, sometimes you will be lucky to hear the launch transient (WW2 subs fire torpedoes usually at periscope depth, which is mostly above the layer) and immediately find it.
Active sonar isn't always the solution because of its limited range and if the sub happens to be lurking very close to the sea bottom (normally in shallow waters), it's difficult to distinguish between the sub and bottom of the sea (sometimes the reason the dd shadowing the sub failed to regain contact long after a depth charge run because the sub is damaged and now simply sitting on the bottom with its engine dead and flooding out of control but somehow managed to survive). Active sonar also have the problem of reduced signal reflection when the enemy sub is facing you with its bow or stern section, which reflexes much less sound back compared to facing you with the port/starboard side.
An alternative is your passive sonar, you can rush to the suspected launch site, full reverse to quickly slow down to a halt, turn off the engine and switch to passive search (which is always on if the ship has it, simply turn off your active sonar), if you can't find anything you can move around a little bit, clear your baffles and hope to catch it. Note that the passive sonar doesn't work very well at high speed because of the increased water flow.
I don't know if it is coded in the AI's behavior but you can first try to pin the sub with the active sonar to let them know you are coming, sending them trying to run away with full speed. Because the current AI subs never dive below test depth willingly, running at full speed will always cause cavitation, which is extremely loud and making the sub easy to find with the passive sonar. (cavitation is indicated with bubbles forming around the screw if you are at a sub's point of view)
Other than that it is basically pure luck if you can rush to the site quick enough before it relocates and becomes almost impossible to detect.

[Lycon]

Początkowo opublikowane przez Luetjens:

You also have to take the weather and sea state into account, with bad weather or rough sea the ambient noise will be very high that it's very hard to pinpoint the sub unless you are directly above it or extremely close to it. Also the existence of a thermal layer will tend to keep the sound travelling between the layer and the surface, masking the sub hiding below layer depth. (you will have a better idea how it works if you have played cold waters, which is focused on ASW warfare) However, if a layer exists and the surface duct is very strong, sometimes you will be lucky to hear the launch transient (WW2 subs fire torpedoes usually at periscope depth, which is mostly above the layer) and immediately find it.
Active sonar isn't always the solution because of its limited range and if the sub happens to be lurking very close to the sea bottom (normally in shallow waters), it's difficult to distinguish between the sub and bottom of the sea (sometimes the reason the dd shadowing the sub failed to regain contact long after a depth charge run because the sub is damaged and now simply sitting on the bottom with its engine dead and flooding out of control but somehow managed to survive). Active sonar also have the problem of reduced signal reflection when the enemy sub is facing you with its bow or stern section, which reflexes much less sound back compared to facing you with the port/starboard side.
An alternative is your passive sonar, you can rush to the suspected launch site, full reverse to quickly slow down to a halt, turn off the engine and switch to passive search (which is always on if the ship has it, simply turn off your active sonar), if you can't find anything you can move around a little bit, clear your baffles and hope to catch it. Note that the passive sonar doesn't work very well at high speed because of the increased water flow.
I don't know if it is coded in the AI's behavior but you can first try to pin the sub with the active sonar to let them know you are coming, sending them trying to run away with full speed. Because the current AI subs never dive below test depth willingly, running at full speed will always cause cavitation, which is extremely loud and making the sub easy to find with the passive sonar. (cavitation is indicated with bubbles forming around the screw if you are at a sub's point of view)
Other than that it is basically pure luck if you can rush to the site quick enough before it relocates and becomes almost impossible to detect.

nice explanation, cheers!

[Steeltrap]

The enemy sub can move at either 7-8 (for IJN) or 8-9 knots (USN).

If you are closing on it at 10 knots, your closing speed is only 1-3 knots.

If the enemy is 2,500-3,000 yards away when it fires then it will take at LEAST 25 MINUTES to close that distance if the sub is heading directly away from you.

3 knots = 6,000yds per hour (a nautical mile is 2,000yds).
That's 1,000yds every 10 minutes. or 100yds per minute.
If you have to close 2,500yds then time in minutes = (2,500/100) = 25 MINUTES!!

Your active sonar has a BEST POSSIBLE range of 2,000yds, It will never BE that because it loses effectiveness based:
- on how quickly your ship is travelling (you start losing effectiveness based on a rate PER KNOT OF SPEED)
- the sea state; anything over sea state 3 starts to cut its effectiveness with increasing significance. It's all but pointless trying to hunt a sub in sea state 6 or more, and I usually don't even bother in sea state 5.
- the facing of the sub. The closer to end on it is, the smaller the area for the sonar ping to strike and thus the weaker the return = lower effective range. I believe a target end on to you applies a 50% penalty.
- if there's a thermal layer. if you go to the conditions report which is F5 it will tell you if there's a layer and its strength. A layer of 80% means your sonar, active or passive, will function at 80% AT BEST.
- there are more but I won't cover them all.

As you can see, if you try hunting a sub at 10 knots FROM THE TIME IT SHOOTS AT YOU then you will almost certainly NEVER find it.

What you need to do is work out roughly from where the torps came and immediately charge at that point at max speed. As you get closer to where it might have moved to given how long it's taken you to get there, you cut your speed to 0 and drift on with your active pinging.
If you're getting down to 5 knots or slower and hear nothing, switch to passive.

As others have said, having TWO DDs is much more effective as one can charge while the other follows up at a lower speed, BUT you still want BOTH to get at least close to the area where the sub might be ASAP.

The game REALLY ought to allow us to mark the suspected point on the map AND then draw a circle around it where the radius = max possible distance the sub might travel in the time it takes YOU to reach the centre of the circle. Thus you could see on the map just where the sub COULD be based on how accurately guessed where it was when you drew the circle.

But we have none of those absolutely basic, "every DD of every nation had such plotting tools" available to us, which is just another example of the incomplete state of the game as sold.

Hope some of this helps along with the other answers.
Cheers

[Lycon]

Początkowo opublikowane przez Steeltrap:

The enemy sub can move at either 7-8 (for IJN) or 8-9 knots (USN).

If you are closing on it at 10 knots, your closing speed is only 1-3 knots.

If the enemy is 2,500-3,000 yards away when it fires then it will take at LEAST 25 MINUTES to close that distance if the sub is heading directly away from you.

3 knots = 6,000yds per hour (a nautical mile is 2,000yds).
That's 1,000yds every 10 minutes. or 100yds per minute.
If you have to close 2,500yds then time in minutes = (2,500/100) = 25 MINUTES!!

Your active sonar has a BEST POSSIBLE range of 2,000yds, It will never BE that because it loses effectiveness based:
- on how quickly your ship is travelling (you start losing effectiveness based on a rate PER KNOT OF SPEED)
- the sea state; anything over sea state 3 starts to cut its effectiveness with increasing significance. It's all but pointless trying to hunt a sub in sea state 6 or more, and I usually don't even bother in sea state 5.
- the facing of the sub. The closer to end on it is, the smaller the area for the sonar ping to strike and thus the weaker the return = lower effective range. I believe a target end on to you applies a 50% penalty.
- if there's a thermal layer. if you go to the conditions report which is F5 it will tell you if there's a layer and its strength. A layer of 80% means your sonar, active or passive, will function at 80% AT BEST.
- there are more but I won't cover them all.

As you can see, if you try hunting a sub at 10 knots FROM THE TIME IT SHOOTS AT YOU then you will almost certainly NEVER find it.

What you need to do is work out roughly from where the torps came and immediately charge at that point at max speed. As you get closer to where it might have moved to given how long it's taken you to get there, you cut your speed to 0 and drift on with your active pinging.
If you're getting down to 5 knots or slower and hear nothing, switch to passive.

As others have said, having TWO DDs is much more effective as one can charge while the other follows up at a lower speed, BUT you still want BOTH to get at least close to the area where the sub might be ASAP.

The game REALLY ought to allow us to mark the suspected point on the map AND then draw a circle around it where the radius = max possible distance the sub might travel in the time it takes YOU to reach the centre of the circle. Thus you could see on the map just where the sub COULD be based on how accurately guessed where it was when you drew the circle.

But we have none of those absolutely basic, "every DD of every nation had such plotting tools" available to us, which is just another example of the incomplete state of the game as sold.

Hope some of this helps along with the other answers.
Cheers

1 more thing, if 1 dd is using active, will that noise kill the others passive?

[Invader ZIM]

I'm surprised the default sonar range is so low under ideal conditions in game.

This was standard US sonar until 1944.
http://pwencycl.kgbudge.com/F/l/Fletcher_class.htm

"QC sent out a beam that was 14 degrees wide in the horizontal direction and so wide in the vertical direction that it gave no depth information. It operated at 24 kHz with a power of up to 300 watts, yielding a maximum range of 3,635 yards (3324m) under perfect conditions on a destroyer steaming at five knots. Range fell off sharply at speeds above ten knots and under realistic sea conditions.:

[Steeltrap]

"1 more thing, if 1 dd is using active, will that noise kill the others passive?"

There's nothing in the manual to suggest so, nor anything in the txt files with all the various modifiers and details of how things work, nor have I ever heard it said by KFG. so I'm going to say no.

I also forgot to add that all the USN 'fleet' subs, the Tambor and Gato classes being successive classes of 'fleet boats', had 6 forward torpedo tubes and 4 aft.
The IJN ones had 6 forward but none aft.
The torpedoes spreads you encounter are indeed realistic in number.

In fact one thing the game tends to get quite accurate is armaments of warships (we'll leaver transports aside as they're absurd abominations).

Cheers