==========
INTRODUCTION
==========
So, chances are that if you're reading this guide, you've gotten pissed at how easy it
is for a sub to sink a BB, and want to do something about it.
Since subs are still relatively new to the game (only having been in it for a fraction of
its existence), submarine tactics and anti-submarine tactics are still nowhere near as
developed as BB and CV tactical doctrine. As a partial result of this, very few people
know how to actually counter subs, and subs are having a fairly easy time attacking
enemy BBs due to this. The goal of this guide is to provide a remedy for that, ASW:
Anti Submarine Warfare. Do note that since, again, ASW tactics are still in their
formative stages compared to CV and BB tactics, this guide is far from
comprehensive, but it does list what I found to be effective in sinking subs before
they make a major dent to your team.
While submarines do have some ridiculous advantages that make them seem
unbalanced (like eating a full Lion 2 salvo without sinking, for one), they also have
various weaknesses that make them easy to sink as well (such as vulnerability to
underwater damage); they're the first truly asymmetrical ship of NF. A BB can do next
to nothing when confronted with an experienced sub, but a sub can similarly do next
to nothing when confronted with a good ASW ship. Now, the learning curve and level
gaps do make this somewhat unfair to the ASW and BB side, but done properly, subs
can be neutralized to good effect.
Much of this guide is geared more towards close-range ASW combat, as that's how
anti-submarine combat has been conducted in the game for the majority of the existence of
submarines, and thus there is more information available on that front. However, new
doctrine for long-range ASW is continually being added, so make sure to check back every
now and then.
=======
THE CREW
=======
There are two types of ASW combat: short range, and long range. Short-range
combat, the more dangerous variant, involves getting up close and personal in the
face of the sub and involves considerable risk as well, but is a more guaranteed way
of dealing with submarines. Long-range combat is safer, but takes more skill to
operate effectively and may also require more advanced ships to use properly. Which
type of combat you use is up to you, but both have different crew and ship
requirements, and thus will be discussed separately.
--------------------------
Close Range Combat
--------------------------
The basic requirement for driving a close-combat ASW ship is one Sonarman and two
Torpedomen. Now, incidentally, this crew setup, minus the Bridge Operator and
gunner, is only one sailor shy of having yourself a submarine crew, a great irony. So
if you find yourself aiming to raise a submarine crew, close-combat ASW is actually a
good way to do that (like how AA whoring is a good way to gain experts on CV
pilots).
While a Sonarman isn't expressly required in order to perform close-range ASW
combat, not having one can be a severe handicap if your ship of choice is a CL.
Sonarmen can see enemy submarines while they are submerged, with the only
exception being when your ship overheats. A DD has its own sonar without the need
for a Sonarman, but having one will extend your visual range somewhat, which helps
you a lot more. So, be sure to raise a Sonarman if you intend to participate in ASW
combat.
Technically only one Torpedoman is needed for a close-combat ASW crew, but again,
if you want to be effective, then two is the way to go. Incidentally, again, two is also
the optimal number of Torpedomen to have on a submarine due to subs having bow
and stern tubes; while the O Class and S Class don't have stern tubes, the
Barracuda does, so starting early is never a bad thing.
Having gunners is optional on close-range ASW ships to deal with surface targets, or
the sub itself if it surfaces to avoid depth charge damage. However, the flip side of
this is that in close-range combat doctrine, speed is a very important factor, and
loading up gunners and guns may slow you down to the point of ineffectiveness. If
you can fit them on, then more power to you; it's not expressly required to have
gunners on a close-range ASW ship, but it can increase your effectiveness if done
right.
-------------------------
Long Range Combat
-------------------------
The requirements for a long-range ASW ship are different, needing only two gunners
and the Bridge Operator, as well as the Sonarman. This setup, excluding the
Sonarman, is part of the absolute minimum setup required to operate a gunship, so
all BB players will be well-equipped to drive a long-range ASW ship. While you can
neglect the Sonarman in this case as with close-range combat, this isn't
recommended, even if it acts as a backup to your combat abilities rather than an aid
in long-range combat.
Gunners are an absolute requirement for long-range ASW ships, for the sole reason
that the recommended long-range ASW weapons will require these sailors. If you have
super high-level gunners then certain ships might not be feasible to use for long-
range combat operations due to weight limitations. A minimum performance level
is recommended for gunners, as the reload times are considerable for long-range
weapons, so be sure to raise your gunners properly.
A Sonarman is not an absolute necessity to perform ASW at long range, but it is
nonetheless instrumental in creating an effective ASW crew. In the case of long-
range ASW combat, your weapons will be able to strike at subs well outside of your
sonar range, so much of the time you will be able to dispatch them without the need
to use your Sonarman. However, conditions will never always be ideal, and
sometimes subs may manage to avoid detection and enter your sonar range, at
which point you will be able to spot the sub if you're carrying a Sonarman. So while
the Sonarman will rarely be used if you do your job right, it can be a very handy
backup that will save your skin if things get too rough. Besides, it comes at level 12, so
it's not really a hurdle to jump at all.
==========
THE WEAPONS
==========
Depending on what range you're going to be operating at, your choice of weapons
will vary. Different weapons have different uses, limitations, and requirements, so
choosing the right weapon for the right situation will be very important. This will also
depend on the ship that you choose to use, which will be discussed later. Again, this
section is split into close-range and long-range tactical doctrine.
----------------------------
Close Range Weapons
----------------------------
-Torpedoes
Fighting fire with fire may seem like a good idea, but in this case torpedoes serve as
poor dedicated ASW weapons. While subs are slow and can't absorb much damage
from torpedo warheads, they also have the ability to critical dive right under your
salvo, which negates just tossing spread after spread at a sub and hoping that it
dies. Furthermore, the Mark 11 and Mark 12 USN torpedoes do fairly poor damage,
and the Mark 15 torpedo isn't available on all USN ships. There's also the fact that
torpedo launchers take a long time to reload, plus they eat up a lot of armament
space that could be used for depth charges if you're operating at close range, so
using these weapons leaves you wide open for attack if you miss.
Overall, using only torpedoes by themselves to sink enemy submarines is not wholly
effective even given that you can attack it from range instead of risking getting sunk
from closing the distance to use depth charges. However, torpedo launchers do have
their uses, not only because they can be used against other enemy ships instead of
just submarines. I'll cover that in more detail later.
-Depth Charges
The bread-and-butter close-range ASW weapon, these things are extremely lethal
against enemy submarines when utilized properly, and are considered the blunt
instrument in ASW doctrine. Their range may seem short since they have to be
dropped off of your ship, but their splash damage radius is quite large (comparable
to that of submarine torpedoes), so even when dropped in relatively near proximity
to an enemy submarine, they can do cripple or kill your target with no problem; four
depth charges detonating in close proximity of a submarine will kill it, no questions
asked. And given that the reload time is on the span of a few seconds, it's possible
to kill an enemy submarine in four seconds flat if you can get close enough, or have a
second salvo ready almost immediately if your first salvo misses or you encounter a
second target immediately after. Even better, the damage is spread over an area
instead of being directed at a single enemy, so dropping charges on top of multiple
enemy submarines will have devastating effects.
The only real weaknesses of depth charges are that they have to be dropped in
proximity of an enemy sub in order to damage it, and that the splash damage is
capable of damaging surfaced friendly ships as well, yourself included. So make sure
that you mount enough bulge to negate or at least minimize the damage that they'll
do to your own ship if it's not fast enough to get away from them before they go off.
-Guns
This may seem like a no-brainer, but it actually is important enough to address this
issue.
The above two weapon systems are only good for close range fighting, and only the
torpedoes can be effectively used against non-submarine targets. So, why not
protect yourself further by mounting guns? The reason is that if you're going to play
a dedicated ASW role, then you don't need to worry about other enemy ships. Plus,
due to the limited choice that you have in picking an ASW ship (to be discussed
below), the weight taken up by the extra equipment may not be beneficial to your
capabilities, of which speed is one major factor.
On the other hand though, if a submarine surfaces against you, then only your
torpedoes and guns will be good against it, and your torpedoes have a safety range,
which might require you moving away and possibly letting the sub get away, or even
worse, firing a spread of torps at you. For that reason, carrying guns may give you
an additional option against subs; but as with normal surface targets, guns are only
useful if you have enough of them or if they're of a large enough caliber to do the
job. So unless you can carry enough guns to destroy a surfaced submarine or can
finish it off after it's crippled by your other weapons, better to simply let a friendly
surface ship kill them while they're on the surface, and stand by with depth charges
ready in case it attempts to dive.
-Hedgehogs
While normally considered a long-range ASW weapon, the hedgehogs (discussed in
more detail below) do have their uses at close to medium ranges. While operating in
close-range ASW combat does require speed and maneuverability, hedgehogs are
not very strict on usage requirements, so if you have gunners that don't weigh a lot,
you can carry hedgehogs and still maintain high speed and maneuverability at the
same time. And should any of your other weapons systems not be ideal for engaging
a submarine, the hedgehogs give you an additional option for destroying your target. Also,
consider the fact that hedgehogs have very short fuse times, so throwing a salvo off at 10
degrees or less will give your target absolutely no time to critical dive, even if they
see the salvo coming.
----------------------------
Long Range Weapons
----------------------------
-Hedgehogs
The newest addition to the ASW arsenal, these weapons allow you to engage and
destroy submarines from well outside of their torpedo range, which is a major
advantage. Furthermore, the requirements for wielding these weapons are relatively
low, so they can be carried on just about any ship. By themselves, they have
completely turned the tables on submarines, turning ASW combat from a risky
proposition into a walk in the park; a competent ASW ship, carrying enough hedgehog
mounts, can wipe out the entire enemy team's submarine force all by itself.
Hedgehogs work very similarly to guns; aim in a direction and at an angle, and the
hedgehog shells will land where you fire them. Each mount fires five shells, which
drop miniature depth charges where they splash in the water; after two seconds,
they'll explode, causing underwater damage to any submarines in the area and giving
them almost no time to react. The effect can be stunning to watch, and direct hits will
leave notifications ringing in your battle report screen for quite a while after the salvo
detonates.
As a last resort, hedgehogs can even be used as surface weapons, and can sink
small surface ships if used right. Each shell does roughly the same amount of
damage as a 7" shell, and can cause considerable damage even to BBs. However,
they're no solid substitute for real surface guns, as the reload time and price obviate
you from using these weapons on a consistent and reliable basis.
The downside of these weapons is that they must be manually aimed, they have
extremely long reload times (comparable to that of ship-mounted torpedo launchers),
and their damage and splash radius is nowhere near as powerful as close-range
depth charges. As a result, carrying at least four mounts in a broadside salvo is highly
recommended if you intend to cripple or kill your target instead of simply harassing
it; furthermore, these mounts must be aimed precisely (more tips on this later), or you'll
miss and be forced to go through a long reload cycle, leaving you open for attack.
However, when used right, you can eliminate submarines well outside of their range, before
they can even get close to your team's BBs. Be warned, however, that the hedgehog depth
charges do very little damage against surface targets, so if you want to damage surfaced
submarines with them, you'll have to hit them directly with the shells, which can be hard
to pull off even firing five shells per mount.
Currently, hedgehogs are mounted in the R mounts of dedicated ASW DD and CL,
and are used as secondary weapons in the T mounts of larger ships that can't afford
to strip off their main armament, or cannot otherwise utilize their T mounts for
something else. In some cases, AA capability is sacrificed for anti-submarine
capability, whether or not you want to do this with your ship is your choice. As a
result, even if you're playing as a dedicated ASW ship, you may sometimes get help
from other ships in destroying submarines, which does help.
One last warning though: unless you have lots of credits to spare, don't use
hedgehogs indiscriminately. At a cost of 500 credits per individual salvo, you will
almost certainly lose credits in every battle that you use hedgehogs in, so if credits
are a major issue for you, play it smart when you use these weapons, or don't use them at
all until you have more credits.
-Guns
Guns on a close-combat ASW ship can be a tricky proposition, but in the case of long-
range ASW combat, speed and maneuverability is not quite as important, and if your
ship is a CL, then you can act in an anti-surface or AA role on top of your ASW duties.
So, if you're not using a ship that has strict limitations on displacement, guns are
generally a good choice on long-range ASW ships, for the further reason that you can
engage the submarine with your guns at range if it surfaces to avoid being damaged
by your hedgehogs.
-Torpedo launchers
Torpedo launchers, used in tandem with other ASW weapons, is only really good at
close range; at long range, as with other ships, submarines can easily discern the
running direction of your spread and avoid it easily. While they can be used to force a
submarine to attempt to submerge in order to critical dive, the optimal range of
hedgehogs is far beyond that of torpedoes, and your guns will have more range and allow
you to sustain more fire on your target. As a result of this, carrying torpedoes in a
long-range configuration is not recommended.
=======
THE SHIPS
=======
Picking a dedicated ASW ship to use is probably the biggest decision to make here.
No one ship serves all purposes, and different ships have different degrees of
effectiveness in different areas, as well as at different ranges. For example, if you
want to be effective not only against submarines but also against surface ships or
planes, then a DD is probably not your best bet. But if you want to be highly effective
against submarines and let your team deal with the surface targets, then an ASW DD
will give you the most bang for your buck in close quarters combat. What ship you
pick will depend on your play style.
In general, picking between a DD and a CL is mainly a choice between speed and
maneuverability versus flexibility and surface firepower. A DD will have a smaller
profile which makes it harder to hit, plus it has higher cruise speeds and
maneuverability, as well as greater close-in ASW capability, but its surface firepower
will leave much to be desired. A CL is generally slower and easier to hit, and not as
capable in the close-range ASW department, but is also more durable and can field
much more surface firepower, as well as take advantage of long-range ASW
weapons. As a result, DDs generally make better dedicated close-range ASW ships,
whereas CLs give a good blend of both close-range ASW and surface staying power,
or can pack a large amount of long-range ASW firepower.
Long-range ASW combat will almost always require a CL, for the reason that in order
to minimize the reload problem with hedgehogs, high-performance gunners will be
needed, and DDs run into displacement problems because of this. While you can
mount hedgehogs on CA and above with no ill effects besides losing AA capability,
this is only recommended if you intend to run ASW as a secondary task, as CAs and
BBs should really be conducting anti-ship combat as their main role.
Remember, only the ships that actually have armament space will be effective in
close-range ASW combat. Not having armament space means not having reloads for
torpedoes and depth charges, which basically makes you a one-shot pony that can
only take on one submarine, max. This isn't as much of an issue with hedgehogs
since their ammunition uses leftover R space like normal guns, but all the same, make
sure that the ship that you choose has enough space to carry reloads.
A side note: if you're running a close-combat ASW DD, mounting a Finder FCS may be
of benefit. Finder FCS has a larger marking range than an Aiming FCS, and unless
you're packing guns you don't need the extra accuracy revision (and even if you do
have guns it doesn't make a drastic difference at the ranges that a DD fights at). The
extra marking range allows you to spot incoming torpedoes farther out, which gives
you an advantage in pinpointing submarines outside of your visual range. For long-
range ASW, however, the best Aiming FCS should always be mounted, not only
because your surface guns will require the additional accuracy, but also in order to
minimize the spread of the hedgehogs themselves.
----------
Fletcher
----------
For a level 12 DD, the Fletcher is a respectable close-range ASW ship that can be
pretty effective when used right. While its main armament doesn't let it deal with
very large surface targets, its two T mounts serve it well for taking on enemy subs.
Also, the fact that it's a DD1 means that most big ships will ignore it or take little
notice of it, allowing it to do its job.
Due to its small R mounts, the Fletcher can also operate as a limited long-range ASW
ship. If you aim well, you can take out submarines at long range, but the limited
ammo means that you have to be very precise at aiming, and you have to expend
your ammo wisely. On top of that, you won't be able to carry very reliable gunners, so
you'll have to be very precise with your aiming since your reload times will be extremely
long. However, with five R mounts, you can virtually eliminate any submarine out there
with a single salvo if you aim right.
As a note, the Fletcher's main armament also allows it to deal with surfaced subs
with fair effectiveness if all five mounts are used with regular guns. It still takes a
while to whittle one down from full health, but if you cripple it beforehand with depth
charges or torpedoes you stand a good chance of finishing it off right then and there.
----------
Gearing
----------
While the Gearing's anti-surface capabilities are considerably greater than the
Fletcher's, its close-range ASW capabilities are still only on par, and its long-range
ASW capabilities are mixed. Due to the weight of the guns it can mount, it may end
up cruising at slower speeds than the Fletcher, which may hurt its close-range ASW
capabilities somewhat. However, if you need to deal more decisively with surface
targets that you may run into while conducting close-combat ASW, then the Gearing
is a good ship.
While you have roughly half the R mounts as a Fletcher, each one comes with
considerably more space, so with a long-range ASW configuration you can use the
extra ammo to play hit-and-run games with submarines with fair reliability, but don't
expect to take down subs with single salvos unless they've been damaged
beforehand. And as with the Fletcher, since DDs have very limited displacement, you'll
probably suffer from long reload times with the hedgehogs.
The Gearing DDR serves more or less the same purpose as the base ship, but has
more anti-surface capabilities when not carrying a long-range ASW setup. The
Timmerman has no close-range ASW capability due to the lack of T mounts, but
it makes up for this by fielding more long-range ASW capability. Again, mind the reload times.
---------
Somers
---------
Its anti-surface capabilities are weak compared to the Gearing family, but when used
in a close combat ASW role, the Somers's three T mounts make it second to none.
While the Somers's T mounts have less space that keep it from mounting the same
ASW gear as the Fletcher and Gearing, it more than makes up for this with its three T
mounts and higher armament space. Despite its flaws as an anti-surface ship, the
advent of submarines has finally given the Somers a place to proudly stand in the
USN lineup.
When fitted in a long-range ASW configuration, the Somers stands roughly on the
same level as the Timmerman; with good aim you can cripple or kill most subs, but
still suffer from the reload issue. Even better, you can combine long-range and short-
range ASW weapons on one platform and absolutely terrorize any submarine foolish
enough to oppose you. But, as with any other DD, you may have to watch the weight
limits carefully, and carrying hedgehogs reduces your anti-surface capabilities to almost
nothing.
---------------
DDX Project
---------------
The DDX carries a very impressive anti-surface battery for a DD, but its single T
mount and low armament space obviate it from participating too much in a close-
range ASW role. As a result, when used in the close-combat configuration, it serves
mainly as a primarily anti-surface and AA ship and stands as an ASW ship in a
secondary role. This isn't necessarily a bad thing though, since it means that a DDX
could clear out any surface targets in its hunting grounds before it concentrates on
killing the enemy sub with depth charges. But on the other hand, players tend to
regard DD3s in a more dangerous sense than a DD1 or even DD2, so you may find
yourself under enemy fire more frequently.
As a long-range ASW ship, on the other hand, the DDX can dominate as easily as a
Fletcher, but without the ammo issues. Aim properly, and you can very easily kill
enemy subs. Provided that you can overcome the weight issue (which is remote but certainly
possible), a long-range ASW DDX can be a formidable opponent.
---------
Omaha
---------
Continuing its reputation as the most flexible NCL in the game, the Omaha can serve
as a reliable ASW ship and still give other ship types more than their fair share to
worry about. Its ridiculously high cruise speed means that it can close in on subs very
quickly while still being able to see them, and its spacious T mounts give it the
capability to carry any ASW weapon on either mount; it is the only USN ship with
armament space capable of carrying the Mark 15 torpedo launchers. Its varied main
battery also gives it the option to either wreak havoc on any CL-sized surface target
or absolutely destroy any enemy plane squadron.
On the other hand though, the Omaha is bigger than a DD, which may make it harder
to dodge enemy torpedoes or shells. Furthermore, its T mounts are single-
directional; one mount only fires starboard and the other only fires port, so mounting
torpedo launchers makes it necessary to keep track of which one is reloading and
which one is ready. The other major problem is that you can only operate one mount
at a time due to only having one slot for a torpedoman on the ship, so if you're
carrying depth charges, you'll have to drop on one side, then swing your guideline to
the other side to drop a second salvo, instead of dropping two salvos at once. This
can be a serious disadvantage since it gives your target more time to react.
---------
Atlanta
---------
Like the Omaha, the Atlanta's reputation precedes it, as CV drivers out there still
shake in fear of one of these ships protecting the ship that it wants to bomb. As a
close-combat ASW ship though, the Atlanta is not quite as flexible due to its relatively
lower speed and turning force, making it a relatively easy target to torpedo. It also
suffers from the problem of carrying single-directional mounts like the Omaha, so its
main ASW armament is also largely relegated to depth charging. However, its anti-
surface capabilities mean that if it can force an enemy submarine to surface, it can
absolutely rip it to shreds in a few seconds, even if it's at full DP. Plus, it has two
sailor slots for the T mounts, so you can drop depth charges off of both sides in a
single salvo unlike the Omaha.
If fitted for a long-range ASW role, the Atlanta class can absolutely devastate any
submarine out there; however, with its firing arc and turning force limitations, you
must play very carefully with this setup.
-----------
Brooklyn
-----------
The Brooklyn deserves special mention here for its unique capabilities. While it has
no armament space and thus cannot serve as a close-combat ASW ship at all, its T
mounts are situated such that it can play as a devastating long-range ASW ship and
serve in surface combat or AA equally well. With eight single-directional mounts, a
Brooklyn can fire off one hedgehog salvo of four mounts, turn around to unmask its other
broadside, and unleash a second barrage in less than ten seconds.
With six total hedgehog salvos available using just the secondary battery, you can very
easily take out any enemy subs you encounter while maintaining a withering volume of
anti-surface fire. Or even better, you can mount hedgehogs on the R mounts as well, and
completely wipe the floor with all the submarines on the opposing team without
breaking a sweat. The second configuration is more expensive and leaves you more
vulnerable to surface ships, so the first configuration is highly recommended, since it
also allows you to deal with the sub if it surfaces.
==============
GENERAL CONCEPTS
==============
OK, now on to part one of the meat of the guide. Once you've picked a ship and a
setup, it's time to get ready to roll. Depending on your setup, you may be 80% lethal
against submarines but only 20% lethal against everything else, or 50% lethal
against submarines and other ship types, or 20% lethal against subs but 80% lethal
against surface ships. But after you pick your pony, it's time to ride it.
This section deals primarily with the basic rules of operating an ASW ship. They
should become second nature over time, but mainly involves common sense.
1. Know your strengths and weaknesses
Basically, depending on your ship and setup, you should play according to how it's
set. For example, if you're in a DD with ASW only, you should try to travel with
surface ships that can deal with enemy surface ships easily so that you don't have
to, or try to wait until the enemy surface ships are too distracted to care about you
before you go sub hunting. If you're in a CL with minor ASW capability and can deal
with enemy planes easily, you should play more of an escort role and be ready to
deal with the enemy subs only when the opportunity presents itself. Bringing an AA
Atlanta into the thick of it is not a wise choice to make, and following a frendly BB
around in a depth-charge laden DD will rarely give you a chance to sink a sub.
2. NEVER take an enemy sub head-on
The most obvious tip you should follow, if you're going to approach an enemy sub to
attack with depth charges, never do so from the direction that its torpedo tubes are
facing. Always approach from an oblique angle, and never give it the opportunity to
bring its tubes to bear on you:
Keep maneuvering out of its firing arcs to keep it from achieving a firing solution on
you. A DD has far more speed and maneuverability than a sub, so make sure to
exploit this as much as possible. This can be hard to do if you're cruising and keeping
track of it, but if you can catch it from an angle where its tubes aren't pointed and
where it would need to traverse to reach you, then you'll have an easier time
catching them.
Another part of this tactic is to use misdirection; a sub can never be 100% sure
whether or not an ASW ship is actually an ASW ship unless it reacts to the sub's
presence or starts attacking it, so one way to take advantage of that is, if you see
an enemy sub on your sonar, don't give it any reason to think that you can see it
until you're in a superior position.
Try continuing in the same direction that you were going before you spotted it, or try
to change course slightly away from it so that it doesn't get the suspicion that you're
trying to get close enough to attack it. Once you're outside of its firing arcs, then it's
safe to make sudden moves to approach or attack it. Some subs will attack small
ships regardless of suspicion though, so if you see an enemy sub turning to bear its
tubes on you, then you should probably hit the overheat and maneuver out of its
way. Worst case, you make it waste torpedoes that would otherwise be expended
on friendly BBs, and best case, you get into an attacking position and sink it before it
can get a firing solution on you.
Do note that some submarines lack rear torpedo tubes, and because of this they
have considerably larger blind spots. Once you know how to identify which
submarines are which, it makes it easier to sneak up on some subs from behind.
3. Watch for friendly fire
Another similarly obvious thing to keep in mind, avoid spamming your ASW weapons
indiscriminately if there are friendly ships around.
Depth charges (close-range ones as well as hedgehogs) do massive damage to
submarines, friendlies included, and the last thing you want to do is sink a friendly
sub by accident. Similarly, torpedoes should be used discretely if there are friendly
ships nearby, surface or not, and hedgehogs should not be fired pell-mell unless
you're confident in your aim, since they can still do damage if the shells land on
surface ships. For this reason, it's usually wise to avoid the sub duels that almost
inevitably occur in the middle of the map (also for reasons of friendly fire hitting you
as well), and try hunting individual submarines. While hedgehogs have enough surgical
precision at medium ranges to break up sub duels in favor of your side (so long as the
subs are not tangled right on top of each other), you should only attempt to do so if you
are confident enough in your aim.
4. Watch your overheat
It's no secret that your sonar doesn't work when you overheat, but what isn't well-
known is that how long it takes for your overheat to come back online is directionally
proportional to how long you overheated. Overheating for 10 seconds keeps your
sonar offline for longer than if you had only overheated for 5 seconds, so for
coverage purposes it's better to make multiple short dashes than to make one long
dash. You can use this to your advantage by using your overheat temporarily to
close the gap between you and your target, but cut it off early so that you have a
clear picture of where your target is when you get there.
For long-range ASW ships, this isn't quite as important since any submarines you're
targetting will probably be outside of your sonar range anyways, but if you're unsure
where a sub has slipped to, run at cruise speed to be careful. The other danger to be
aware of is that in a long-range ASW ship, you'll probably be carrying an Engineer or two,
which will increase your overheat time and put you at a disadvantage if you inadvertently
leave it on. So, as crazy as it sounds, try to leave your Engineers behind when driving an
ASW ship.
One more caution: if you absolutely must use your sonar, be sure to drop down a knot or
two below cruise speed! While it doesn't happen often, there is a bug that makes the game
think that you're overheating even if you're simply going at cruise speed; so, to be safe,
be sure to drop a knot below cruise speed so that you don't have to fight blind at an
inopportune moment.
5. When in doubt, drop indiscriminately
Seems stupid, but it works. If your sonar is offline (from still overheating or just
coming off of a long overheat) and you know that an enemy submarine is within
depth charge range, then it's not always a bad idea to just drop a few loads of close-
range depth charges in random places and watch if your attack counter goes up.
As I mentioned, the splash damage radius for rack-deployed depth charges is pretty
big, so even if it's not directly on top of the sub, it will still do serious damage to it.
When combined in spades, you stand a good chance of crippling or sinking the
enemy sub unless it surfaces or critical dives. The critical dive is what you need to
watch out for, since you might wander too far away from it and allow it to attack you.
But on the flip side, if you do force an enemy sub to critical dive and you see where it
was, then you've won, since you can just circle while it's losing DP, and it will have no
choice but to return to normal depth and eat depth charges. The only problem here is
that you can damage yourself with your own depth charges, so either make sure that
you have a lot of bulge or that you drop them where you can get away from.
This can be done to a lesser extent with hedgehogs, but is not highly recommended
since the splash radius on hedgehog-deployed depth charges is nowhere near as
great (and indiscriminately dropping hedgehogs will seriously hurt your credit bank). If
you have multiple mounts and are confident in your estimate, then dropping salvos on
gradual fire may result in some hits, but as hedgehogs are not as powerful as
ship-dropped depth charges, you'll likely only end up harassing the submarine
rather than deal serious damage to it, and worse, be caught going through a reloading
cycle when you actually discover the sub's location. So it's almost always safer to
save your salvo until you're definitely sure of where it is, rather than risk wasting a
salvo. Having more than one broadside helps, but this also brings up the problem of
having to turn your ship if the broadside that you just emptied is the side where you
find the sub, which costs you time and leaves you vulnerable to attack as you
maneuver.
6. Be wary of other ships
While an ASW ship is highly lethal against enemy submarines, the short-range
variant aren't so much against other ship types depending on what weapons are
mounted. In a generic GB1 room, there will always be multiple small ships that rush
towards the other side in the beginning, and these can actually pose a threat to you
if you're in an ASW ship, since you can't just shrug off small shells like a BB.
Furthermore, some of these ships actually make it a point to attack ASW ships to
protect their team's subs, so at the minimum make sure that your team discourages
them from getting too close to you, or wait until they're dead before venturing out.
Enemy BBs may also be a problem. Most will usually ignore DDs, but if you're the only
target in range then you'll be shot at, DD or not. In general, try to make sure that
there's another friendly ship nearby that can serve as a distraction, or at least make
sure that your team's BBs are keeping them preoccupied.
This applies more or less to long-range ASW ships as well, though in some cases you only
really need to worry about BBs and up, since CLs can carry enough surface firepower to take
care of themselves. While you'll likely be well outside of the range of the middle-of-the-map
brawl, you'll still be a rather juicy target for enemy BBs. So even if you're not getting into
the thick of it, be sure not to stick your neck too far out to get the sub. Ultimately,
it's all
up to your own judgment to decide when to attack an approaching sub, which only
experience will teach you.
7. Humping is legal
This is something more to take advantage of the sub's low maneuverability and
dependence on torps than your own capabilities. If you're carrying only short-range
ASW weapons and get on top of an enemy sub that surfaces before you can destroy
it, then you can still neutralize it by cruising in front of it (within its safety range) and
making its torpedoes dud.
It will be unable to attack anything at all, and you can keep it pinned until a friendly
anti-surface ship arrives on station to pulverize it; if it dives to avoid surface fire, it
has no choice but to die to depth charges. Even better if you have guns or
hedgehogs, then you can damage the sub even if it's surfaced, and possibly force it
to dive. But watch out for the subs that carry deck guns (though very very few do),
those can ruin your day.
=============
GENERAL TACTICS
=============
Part two. The following sections deal primarily with specific tactics that you should
use in engaging enemy submarines when you encounter one or prepare to
encounter it. It's by no means comprehensive, but once you learn to do these things,
it opens the door for more improvement. Three types of tactics will be discussed,
general, close-range, and long-range.
1. Watch the split and position accordingly
This follows the same principle that an AA escort ship does against CVs. When the
room is split and counting down, watch where the submarines on the enemy team
start and place yourself in a blocking position accordingly. Also be sure to watch
where the friendly subs are positioned, you don't want them taking your food from
you and you don't want to damage them with your ASW weapons by accident either;
also, you'll want your team to have as few ASW gaps as possible, so if you see a
flank that an enemy submarine might try to attack but no friendly submarine opposing
it, then it's up to you to make sure that that enemy sub doesn't get a free meal.
Once the battle is under way, be sure to keep track of where the enemy submarine
positions are. Subs won't dive right away, so while the beginning-of-the-game scout
frenzy is still on, watch where the enemy submarines are moving, and position
yourself accordingly. In CLs and higher, you can even launch your own scouts and
stalk the enemy yourself; however, in most cases, scouting the enemy BBs still
takes priority.
Pre-positioning during the countdown is not a huge issue here, since you will
have much more speed than the submarines you are tracking and can maneuver at
will. But all the same, avoid picking a position on one flank and then finding out that
your target has chosen the other flank, since wasting time trying to get into position
will leave you with less time to plan and position for your attack. If you're unsure
about where to go, sticking in the middle is usually a wise choice, and then
committing only when you confirm the heading of your target.
Try to keep track of the enemy subs for as long as possible before they dive, so you
know the general direction that they're going and can head them off. Also, be sure to
take advantage of friendly subs' sonar radius and confirm an enemy sub's heading
once they're under water. With hedgehogs, this will be a crucial advantage, since
your range allows you to take them out shortly after they've dived, denying them any
chance to attack at all.
2. Use a picket
Battles are far more fun when there's teamwork, and this applies to ASW more than
anywhere else. If you have a friendly ASW ship (or even a friendly submarine)
traveling with you, then you can wreak absolute havoc on any enemy submarine that
crosses your path. Your sonar detection area can effectively double if you support
each other properly, and when you do encounter a sub one ship can serve as the
sonar picket while the other can overheat with no worries and get within easy range
of the sub. The only caution here is to, as above, watch for friendly fire. Dont fire a
torpedo arc at the sub when your teammate is on the other side, and don't drop
depth charges on it when your teammate is at a similar distance.
Who plays the picket normally depends on what the ships are; if you're the ASW ship
and a friendly sub is tagging along, then the sub should act as the picket, since sub
duels normally end in stalemates or worse. Similarly, a sub can simply stay at range
and use critical dive to avoid incoming torpedoes, since subs tend to target each
other quite often, and this can serve as a nice distraction for the ASW ship to make
its move.
With long-range ASW, this advantage virtually guarantees the destruction of the
enemy submarine, as you can precisely place your hedgehog salvo right on top of
your target, allowing you to cripple or sink them with ease so long as your picket is
not too close. Just be sure that your target isn't in a situation where they can critical
dive under your hedgehog salvo, or hold your salvo until you see your target critical
dive, and prepare it for when you see them emerge.
================
SHORT RANGE TACTICS
================
When engaging in close-combat ASW, knowing how to deal with a smart opponent
can be the key to victory. Sub drivers do not like to be detected or attacked, so you
will almost always be first on their priority lists; some will even fanatically pursue you
instead of attempting to go after the capital ships on your side. However, if you know
what to do, then you will always be the victor.
1. When in doubt, tire them out
This idea comes mainly from what I've observed of KM ships, and it can be partially
applied here.
On the chance that an enemy sub attempts to approach and attack you, and you
don't have the option of attacking it at range, you have the option of using your high
speed and maneuverability to avoid the attacks. In this case, it can pay to play
passively. Stay at range and let the enemy sub fire at you, then use your speed to
avoid the torpedoes and keep away from the enemy. The goal here is to force the
sub to waste torpedoes and air time shooting at and engaging you; at any time
immediately after an enemy salvo you can choose to switch to aggressive tactics and
close in on them while they're reloading, but this can be unpredictable since they
may be holding torpedoes in reserve for such an occasion.
Again, the point of this tactic is to tire them out; the more torpedoes they shoot at
you, the less they have left to shoot at friendly capital ships; the more time they
spend engaging you, the less oxygen time they have, which forces them to surface
and become vulnerable to surface fire from friendly ships. When an enemy sub is
submerged, time is always on your side.
The same concept can be used to defeat the submarine with long-range ASW. Even if
you're not carrying hedgehogs, someone else on your team might, and keeping the
sub occupied until that person can get within firing range will mean an easy victory.
Even better, most submarine drivers believe that they are safer submerged than
they are surfaced, which means that being suddenly attacked by hedgehogs can
serve as a very rude awakening.
2. Pin and destroy
This is the main aggressive close-range tactic that I use to sink subs, and it has
proven highly effective for me.
Simply put, have your two torpedomen load two sets of ASW weapons; one controls
depth charges, and the other controls torpedoes. Keep them on separate Z and C
controls so that you can use them independently. When you encounter an enemy
sub, make sure that you have a good solution on it, then fire your torpedoes at it,
and immediately switch to depth charges and turn in towards it. If you aimed right,
the enemy sub will see the torpedoes coming and will critical dive to avoid the salvo,
but once it come back up, you'll be ready to drop depth charges on it. Even if the
torpedoes miss, you force the sub to maneuver predictably, which still lets you get
within depth charging range.
This setup can be a bit comlex to wield, but used properly, it can result in sinking the
enemy submarine at least 80% of the time, all other things equal. In general, this
can only be done with ships that have two or more omni-directional mounts; the
Fletcher and Gearing families can do this, but the Somers is the king of this setup;
with one torpedo launcher and two depth charge launchers, you can pin or damage
an enemy sub with the torpedo salvo and then charge in to finish it off with a single
depth charge salvo while it scrambles to avoid the torpedoes or comes up from its
crash dive.
Do note that in this case, the torpedoes serve as diversionary tools rather than
actual weapons for destroying the submarine. Whether or not they hit their target is
secondary to forcing the sub driver to focus on the incoming torpedoes and react to
them, giving you the initiative to approach and deliver an attack that they cannot
react to.
===============
LONG RANGE TACTICS
===============
Long-range ASW doctrine is still in its infant stages, so there's not a lot to say here
yet. While you can attack at will at ranges where the submarine cannot reply, you
also don't have the benefit of being able to use your Sonarman to pick up the sub's
location, and you have to be more precise with your aim instead of simply applying a
blunt instrument and making a big mess.
1. Bracket marking
The same concept that is used on gunships, at the beginning of the game you can
mark your range by firing a broadside at a certain angle to get a known range
reference. In the case of ASW, however, you won't always be fighting at maximum
range, so marking your lower angles may help. To do this, simply switch your guns to
gradual mode, and then fire one hedgehog mount at a time at various angles. I
personally use angle 20 and 30 as reference markers, so that my very first salvo
will be dead-on. As with capital ships, keeping your opponent at max range may help
make aiming easier.
There are two things to consider though. First, depending on how large your mounts
are, ammo limitations may not permit you to fire marking salvos; if this is the case,
then simply making one marker at max range will suffice, but if you're going to drive
an ASW ship, then hopefully you're packing more than simply one or two salvos of
hedgehogs. Second, unless you're carrying multiple broadsides, your marking salvo
will only be good for your first attack since your FCS only keeps track of four shell
markers per mount, and because each mount fires five shells, firing a broadside will
immediately erase any markers you have placed for it; so make sure that you know
your angles well despite the markers, or try to fight at max range whenever possible.
2. Range & safety vs. precision & surprise
One thing to keep in mind about hedgehogs is, since they work like guns, you have to gauge
distances very carefully whenever you choose to attack a target.
As with other low-caliber guns, the farther the range, the worse the shell spread will be,
the less effective your salvo will be. Even though hedgehogs do underwater splash damage,
at higher angles (30 and up) your salvo will spread over a fairly large area, which means
that while you stand a better chance of doing at least some damage to your target, you'll
do less damage since the charges will be farther apart and thus fewer will be close enough
to do actual damage. While having good gunners can help to limit this, even at high levels
there are no guarantees.
The second thing to keep in mind is that, like battleship-caliber guns, a lower slinging
angle gives your opponent less time to dodge, or in this case, to hit the critical dive
button. Some submarine drivers keep track of who carries hedgehogs, so if they see a salvo
fly at them the first thing they'll do is hit the critical dive and dive under your salvo,
thus wasting your salvo and forcing you to reload. But at lower angles (and thus closer
range), they'll have less time to react and might not be able to dive in time (or even
better, hit the bottom after your salvo connects, and sink themselves with critical dive
damage). Of course, the flip side is that at closer ranges, they may just put a torpedo
into you, so whenever possible, try to do this from their broadside or at angles not too
much below 15.
3. Stalking
The main problem with hedgehogs is that you are nearly impotent against the sub
so long as it is on the surface, and so you will have to wait for it to dive before
you can destroy it. However, this is really a double-edged sword, since you'll be able to
stalk your prey while it's on the surface, which also applies to close-range combat, but
in this case you'll have more tactical options to engage since a CL has far more
flexibility than a DD. Keep them within visual range by using your scout whenever needed,
approach within firing range and keep them at a safe distance, and then wait for them to
start diving before you make your attack. Even if they know that you're carrying
hedgehogs, no submarine can critical dive in time if you fire your salvo as they begin
their dive. If needed, you can even use your surface guns to harass it at range and force
it to dive, and then attack with your hedgehogs.
The main problem with this is, if you're keeping a safe distance from the enemy BBs,
the enemy sub will likely dive before you can get within range, which reduces you to
a guessing game. At this point, you have three options: hope that a friendly sonar-capable
ship will reveal the sub's position for you, guess the sub's heading and position and
conduct an attack on that guess, or slow down to cruise speed and use your sonar to detect
and attack the sub at medium range.
In most cases a sub will have to traverse areas patrolled by DDs or other subs, so
waiting for one of these ships to pick up the sub is not as futile as it sounds. If this
isn't the case though, then waiting for the submarine to attack a friendly ship and
then attacking down the axis of the torpedo will also work, though this is of course
less preferable to eliminating the sub before it can do any harm to your team. As always,
be sure to aim precisely so you don't accidentally hit any friendly ships.
The second option is more feasible if it dives not too far outside of your range.
Remember that subs move very slowly and have very little maneuverability on the
surface, and that this applies doubly so when they are submerged; furthermore,
because of their limited air time, most subs will move in direct bee-lines either directly
east/west or towards the nearest group of BBs; both of these factors combine to
make it easy to predict a submarine's heading and location. While this is still
imprecise, tossing out multiple salvos of hedgehogs at a suspected area and
watching where they do damage is a good way to expose a sub's location, and you
may be surprised at how often you can get a lucky salvo that destroys the sub.
The final option is a bit dangerous since long-range ASW ships are not always as fast
and maneuverable as close-combat ASW ships, but if you play smart the risk will be
minimal. With a good Sonarman, you'll be able to spot enemy subs at a tolerable
range (20-25 degrees) and attack them before they can get torpedoes off, but the risk
remains that they'll be somewhat too close for comfort, and you may occasionally be sunk
while attempting this. The upshot, though, is that since you'll be running at cruise
speed, you'll likely be forced to sit back a bit on line with your team's BBs, which
reduces the chances of you getting shot at by an enemy BB; and if you're good at
intercepting the enemy's predicted path, you can position yourself a bit off of its path
and reduce the risk to yourself as the sub guns for a BB on your team. Be warned, though,
that this approach relies on knowing your close angles more intimately, and while bracket
marking at low angles may assist in this, as above, remember that it only helps with the
first salvo.
4. Medium range combat
This bears its own section here since it is a very precise and guaranteed way to take down
submarines.
The concept, simply put, is to always drive at cruise speeds and have your sonar
constantly active, and directly intercept submarines and engage them at angles less than
30. The advantage is that you will always have your target in sight and in range, so they
won't be able to escape once you lock onto them, as long as you don't mess up your
hedgehog salvos. However, the caveat is that you'll have less maneuverability in the event
that they try to close in on you, unless you choose to overheat away and re-engage them
later. The other problem is that at cruise speeds, it will be very easy for an enemy BB to
shoot at you, so don't stray too far from your BB line if you want to do this.
At medium ranges, always try to destroy your target before they can get to 15 degrees,
otherwise they may get into torpedo range and shoot at you. However, if you have a good
cruise speed (30 or so), you can simply elect to cruise away from them and keep a constant
distance from them. Submarines are slow, and so long as they're submerged they can't catch
up to you; if they surface to chase, you can pulverize them with your main guns, otherwise
you can laugh as you drop hedgehogs on them at a range that they cannot reply at.
5. Fake sucker punch
Some more experienced submarine drivers will always have a finger on their critical dive
key, in order to counter any potential surprise hedgehog attacks. This, of course, relies
on taking advantage of the hedgehog's long reload time, so that they'll be able to
continue on their way safely after the ASW ship uses its salvo. However, the counter to
this is very simple, and has no counter itself, just like the Pin and Destroy tactic for
close-range ASW.
Simply put, if you encounter an experienced submarine driver, set your hedgehogs to
gradual fire, and fire only once when you see them. Your target will critical dive upon
seeing this first salvo launched at them, and will probably successfully avoid it. But at
this point, you've pinned them down, since when they return to normal depth, you'll have
your remaining mounts pointed and ready to fire the moment you see them, and no submarine
can critical dive again quickly enough to avoid that. Using this method, as long as your
aim is good and you have a sonar on top of them, you will destroy any submarine out there.
Even if they know what's coming and don't critical dive after your first shot, there's
nothing they can do since you can simply continue to fire slowly on gradual, and if they
surface you'll be able to take them out with surface guns.
There are two cautionary notes here, of course.
First, relying on the sonar of a friendly ship is not recommended, since a surface ship
may overheat suddenly and leave you blind, so if possible, use your own sonar to
illuminate your prey, since you can control your own speed. This, of course, would mean
that you will have to engage in medium range combat rather than long range, but it can't
be avoided, and a good Sonarman will let you keep your targets at arm's length away anyways.
Second, some submarines out there will carry Restorers instead of Engineers, in an attempt
to raise the amount of Soft Defense available, and thus actually survive your second
barrage. Sadly, there's no real way to avoid this except by carrying more mounts and/or
broadsides; carrying a second broadside is recommended since there is no submarine out
there that can survive two direct hedgehog barrages, 900 SD or not. But on the flip side,
even if you don't kill your prey, you stand a very good chance of crippling it, and thus
allowing you to switch to your surface guns and go to town on it.
As a final parting thought, watch the following video demonstrating the use of
hedgehogs:
http://www.youtube.com/watch?v=ClY1JzWlH3E
The video demonstrates several concepts:
1. You can see that I did some bracket marking beforehand, and my guidelines clearly
show the ranges for salvos fired at 20, 30, and 40 degrees. This allowed me to
compute a firing solution at any time while the sub was visible.
2. I didn't fire my hedgehog salvo while the submarine was surfaced. The salvo fired
by the DDX at 0:05 did minimal damage to the sub, since only one shell hit and that
had repaired only 13 seconds after the impact.
3. The splash damage radius is very small and does little to no damage to surface
ships. The second hedgehog salvo that hits at 0:12 does no splash damage at all to
the submarine, as indicated by the attack score not increasing when the salvo
detonates at 0:15, which also illustrates the poor splash radius of the hedgehogs.
4. I only plotted a firing solution when I saw the sub begin to submerge at 0:32. This
is where the bracket marking helped me, since it submerged very close to the 30
degree mark, and I estimated that it would close the distance after submerging so I
lowered the angle slightly, to 28. My salvo would have been fired earlier had I not
been forced to maneuver to avoid crossing the H39.
5. Roughly a third of the hedgehog charges which detonated at 0:42 were close
enough to cause damage to the sub, so out of a salvo of 25, an estimated 8 charges
caused roughly 10k damage, not counting any overkill which may have been
discounted.
A precisely aimed hedgehog salvo, with a broadside of 4 mounts, is usually enough
to sink most SS2, since those usually take roughly 12-14k damage to destroy. For
SS3 and above though, especially those with high-level Restorers, it's not unusual to
be forced to do 17-23k damage in order to kill them. This illustrates the usefulness of
carrying more than one broadside of hedgehogs, since no submarine can survive a
direct hit from two full broadsides of hedgehogs while submerged. In the case of the
video, had my first salvo not done enough damage or simply missed, I had the option
of using my T mounts to deliver a second salvo, and then turning 180 degrees to fire
a third salvo if that wasn't enough. This, of course, would have left me vulnerable to
attack had another sub arrived on the scene while I reloaded, but in the situation
presented in the video, there was only one submarine on each side, so I was free to
empty my magazines on it.
============
FOR THE OTHERS
============
Now, for all those non-dedicated-ASW ships out there, what can you do to counter
the sub threat? A lot, actually. While you may not be properly equipped to destroy a
submarine all by yourself, you can assist in such a way to guarantee the destruction
of that submarine by friendly ASW forces.
1. Don't ignore them
One of the biggest mistakes that capital ships make very often is that they ignore
submarines even after a warning is sounded, or even when torpedoes are
approaching. This is the biggest factor to survival; if you see a sub, then help out the
ASW ships on your team by telling them where you saw it, so that they can get there
to dispose of it. Furthermore, don't just keep driving in straight lines after getting hit
by torpedoes, that just makes you an easy target.
2. Turn towards the torpedoes
This is actually sort of counter-sensible, but it does work. If you see torpedoes
coming at your capital ship, then instead of turning to run away, turn towards them.
Remember that submarines have to aim at you to hit you, and that they have the
least speed and maneuverability in the game; if you can get on top of them then you
force them to move away and turn around to reacquire you, or turn to aim at a
different target; when you're on top, make sure to keep making radical turns to
throw off their aim if they continue to target you. If you just turn away and run, then
they don't have to change their aim and can just keep on firing torpedoes in the
same direction, which is a bad thing.
3. Torpedo bombers work
For CV with torpedo bombers, this can serve as an effective way to eliminate a sub
that's been sighted. The very nature of torpedoes allows them to hit any and all
ships, submarines included, and submarines can't take a lot of underwater damage.
Hitting a sub with even two torpedoes while it's still far from a target will usually be
enough to put it out of action for the rest of the game, or at the minimum make it
considerably easier to dispose of.
The issue though, is targeting it; if it's on the surface and you aim your bombers at it,
chances are that it will try to dive to disable your auto-targeting. But remember that
subs are slow, so if you keep aiming them at where it was and is going to be, you
can probably still land one or two hits. The problem is that if you're too far away, it
may have time to critical dive, or you may miss altogether. So make sure that if you're
going to use torpedo bombers to sink a sub, give it as little warning as possible; fly
the bombers at sea level, and fly them in a passing direction so that it doesn't get
suspicious, only turning to attack at the last moment.
As with all other methods of attack, revealing the submarine with sonar will make
your job all the easier. In that case, the only option the submarine has is the critical
dive, which, in the presence of sonar-equipped ships, will usually spell doom. You can
even keep your torpedo bombers hovering over the spot waiting for the submarine
to emerge, worrying only about any enemy fighters that may arrive to save the sub,
and any AA ships in the area.
4. Consider carrying hedgehogs
While most capital ships will not have the option of carrying hedgehogs due to limited
armament space, this is not true for the case of hedgehogs. In some cases, should
you either decide not to use AA or not have the ability to carry a feasible broadside
(as may be the case in the pre-remodel Standard BB1s and the Yorktown),
hedgehogs may greatly assist in the efforts of ASW ships on your team. While you
yourself cannot spot submarines and lack the maneuverability to avoid them, you
have the option of attacking submarines that have been spotted by sonar-capable
ships, or at the minimum harrassing them and giving them second thoughts about
continuing their approach. Best case, you can destroy the submarine yourself using
the methods detailed in the stalking tactic for long-range ASW doctrine, and worst
case you can damage the sub somewhat and assist in making the job of the ASW
ships easier.