Wet Naval Themed Equipment & Weaponry

[Retry]

I've been intrigued with the idea of blue water and brown water naval forces in Battletech, but there's very few canon vehicles to work off of, and many of the few that do exist are kind of boring. I partially attribute this to the lack of equipment to work with, which basically means the LRTs (and maybe long-range energy weapons or laser AMS) are the only really viable underwater weapon, which is a bit boring. So I'm working on a small naval-themed expansion of the equipment list to make more weapons viable and to give wet navy & amphibious units some different, interesting things to work with. A lot of them are simple "duh" modifications (Multi-Torpedo Launchers), some are basically Battletech conversions of real-life devices (Depth Charges, "Hedgehog" mortars). There's some new stuff, but generally I tried to make stuff fairly intuitive and not too exotic for this run.

MISSILE LAUNCHERS
Torpedo and multi-purpose Missile launchers are extremely popular, common and effective weapons on water-covered worlds.

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Multi-Torpedo Launchers
The MTL is functionally a torpedo version of the Multi-Missile Launcher. Its tonnage/crits/heat/costs functions like that of
 a similarly sized Multi-Missile Launcher, with the only difference being that the MTL fires Torpedos instead of Missiles.

Extended Long-Range Torpedo Launchers
Like the MTL, the eLRT is functionally a torpedo version of the Extended LRM. Tonnage/crits/heat/costs/etc are like a
similarly sized eLRM, with the only difference being that the eLRT fires torpedos instead of missiles.
Note that in Double Blind mode, underwater visibility is effectively 30 hexes at best, so the eLRM will not necessarily be
able to use its maximum range.

Enhanced Long-Range Torpedo Launchers
Like the MTL, the nLRT is functionally a torpedo version of the enhanced LRM. Tonnage/crits/heat/costs/etc are like a
similarly sized nLRM, with the only difference being that the nLRT fires torpedos instead of missiles.

Streak Torpedo Launchers
A Streak LRM or SRM launcher can be made into a Torpedo Version. Again, it functions like a Streak Torpedo version of
the standard launcher with no other changes.

Harpoon 5/10/15/20
The Harpoon Missile Launcher is a Torpedo version of the Thunderbolt Missile Launcher. It's otherwise identical to the
Thunderbolt Launchers of the same size.
In addition, the Harpoon 5/10/15/20 tends to poke much bigger holes than SRMs or LRMs, increasing the probability of a
breach. The target number for breaching is reduced by -1/-2/-3/-4 for the Harpoon 10/15/20 respectively (so a Harpoon
20 that hits a submerged submarine will be breached on a roll of 10-4=6 or higher)

Narc & iNarc Torpedo Launcher
The Narc & iNarc Torpedo Launcher is a Torpedo version of the Narc & iNarc Missile Launcher. It's otherwise identical to
the Narc & iNarc Missile launcher.

Multi-Purpose Missile Launcher
Multi-Purpose Missile Launchers aren't a new weapon per se, but a modification to existing LRMs or LRTs that allow them
to be more versatile by allowing them to be compatible with either missiles or torpedos. Otherwise, the only functional
change to the launcher due to this modification is a 50% increase in C-Bill cost to the Launcher, an increase in Tech
Rating and Availability Rating by 1 level (A tech rating C LRM becomes a tech rating D MP-LRM), and the ability to fire
Multipurpose Missile ammunition normally available only to Battle Armor.
Launchers that can be modified in such a way include: LRMs, SRMs, nLRMs, eLRMs, and MMLs
Either Torpedo Launchers or Missile Launchers may be modified as a Multi-Purpose Launcher. For instance, a MP-LRM is
effectively identical to a MP-LRT.

ALTERNATIVE TORPEDO AMMO

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Multi-Purpose Missile Ammo
This ammunition behaves identically to BA Multi-Purpose Missile Ammo with respect to tech rating and availability, and is
very difficult to find inside the Inner Sphere and generally requires being supplied by clan Sea Fox dealers. The ammo is
2x as heavy as normal ammo (resulting in half the ammo per ton) and costs 2x as much C-Bills per ton and takes the
availability and tech rating of their BA counterparts.
Since the Clans are the only current producers of multi-purpose ammo, only regular SRMs and LRMs have MP ammo
available at this time.
MP-LRMs can fire at a target underwater from above water or vice versa even without line-of-sight using the Indirect Fire
procedure, which requires a spotter.

Turbid Torpedo Ammo
This ammo is effectively a underwater version of smoke ammo and has the cost, tech rating and availability rating equal
to that of its smoke ammo equivalent. Turbid Ammo is available to any torpedo launcher whose missile equivalent can
also carry smoke missiles. The smoke effect can never get above the surface of the water (ex: 2 surface boats duking it
out will not benefit from Turbid ammo below the water)
Turbid Ammo uses a ton of particulate to effectively creates localized Heavy Turbid effects in the water hex it's fired at,
which is functionally smoke for water. If keeping close track of elevation for the purposes of firing arcs and cover, like when
using the Diagramming Line of Sight rules in Tac Ops, the player may fire the Turbid round at a specific depth, in which
case the "smoke effect" will rise and fall 1 hexes from the hex of impact for an effective height of 3. Use the same rules
that you'd use with Smoke to keep track of Turbid effects, migrations, and dissipation.

Narc-Capable Torpedo Ammo
Narc-Capable ammo for Torpedos.
Other than following all the Narc rules, a Narc-capable Torpedo round can fire at targets that they detect with sensors
during double-blind mode (i.e. get a "blip") even if they can't actually visually detect the target, as long as the target has
a Narc beacon attached to it. When firing blind in this fashion, add a +1 to the to-hit roll. The player rolls to-hit as usual
but the GM does not tell the player the target to-hit numbers or whether the player hits the target.
The firing unit is presumed to fire in direct fire when used in this fashion, so if there's an obstacle in the way (like an
underwater building or mountain), the shot will automatically miss.

Semi-Guided Torpedo Ammo
Semi-Guided ammo for underwater

Swarm Torpedo Ammo
Swarm ammo for Torpedos

I-Swarm Torpedo Ammo
I-Swarm ammo for Torpedos

Tandem-Charge Torpedo Ammo
Tandem-Charge ammo for Torpedos
In addition to its normal effects, reduce the target number to cause a hull breach by -1 (so a displacement hull is
breached by a roll of 9 instead of 10 by the torpedo weapon). Units with Harjel liners (new equipment, shown below)
ignore their bonus against hull breaches but do not benefit from the -1 bonus that T-C ammo usually has. T-C ammo is
exceptional at poking holes, so it still rolls for a breach even against Harjel units with a +1/+2/+3 modifier for Harjel
1/2/3. However, this effect is ignored if the unit mounts an armor type that nullifies the penetrative effects of T-C ammo,
such as Ferro-Lamellor, Reactive, and Hardened Armor.
ARROW IV AMMO
The Versatile Arrow IV Launcher had new ammo types introduced in 3050 specifically for underwater usage, increasing their utility in underwater combat and acting as makeshift underwater artillery.

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Trident IV Ammo
Trident IV Ammo is basically an underwater version of the regular Arrow IV explosive round, or a motorized Depth
Charge if you prefer. The firing unit can target any depth from the water-air interface on the surface to the bedrock and
everywhere in between, if so desired. Price, tech rating, and availability rating is assumed to be equivalent to the Arrow
IV in all circumstances, except Pre-3050 where they don't actually exist yet.
In all cases, the Trident IV firer must be submerged in water and the target must also be in water or on the surface of
the water. The traveling path from the firer to the hex must have at least Depth 1 water across the entire path (ex: you
can't fire from the ocean into a 'Mech in a lake or in an isolated Lagoon). Trident IV rounds have the same range in
mapsheets as Arrow IV rounds but travel only 2 mapsheets per turn on the ground map instead of ~8 (IIRC) per turn
like a normal Arrow IV, accounting for the high fluid friction of water.
Hovercraft, WiGEs, Aircraft, and VTOLs with Arrow IVs mounted can use Trident IVs as long as they are over the water.
VTOLs and Aircraft don't even need to land on the water to use a Trident IV, they're just assumed to be firing from the
surface of the water over their current location.

Trident IV Homing Ammo
Funtionally identical to the Arrow IV Homing ammo, but underwater.
Assume TAG works underwater, that the normal TAG has the reduced range brackets of the Large Laser and the Light
TAG has the reduced range brackets of the medium laser when used underwater.
Available as a munition type on Aircraft Hardpoints, in which case it takes up 5 hardpoints.

Trident IV Illumination Ammo
Functionally identical to the Arrow IV Illumination ammo, but underwater.

Trident IV Turbid Ammo
Acts like LRT/SRT Turbid Ammo shown above, but for Underwater Arrows. Virtually identical to Smoke Arrow IVs in a
sense. The round has a radius of R1, just like Arrow IV smoke rounds.

Trident IV Laser-Inhibiting Ammo
Functionally identical to the Laser-Inhibiting Ammo of the Arrow IV's Laser Inhibiting Ammo, but underwater.

Trident IV Charybdis Ammo
One of two actually unique Trident IV rounds, the Charybdis round aims to generate kills against multiple bogeys by
sheer number of breaches. A Charybdis rounds is essentially a Radius-3 highly modified Cluster Round that deals only 4
damage per hex, but in clusters of 1 point each, with each point rolling for hull breaches like normal.
Cost is 2x that of a normal Arrow IV warhead, with the tech rating of F and E for the IS and Clans, respectively, and with
availability ratings of F for both.

Trident IV Scylla Ammo
One of two actually unique Trident IV rounds, the Scylla resembles a huge tandem-charge warhead and is aimed at
crippling large naval vessels or unfortunate Dropships parked in an ocean by creating a Breach. The Scylla has a radius
of R0 and is unguided so it's very tricky to hit small and even larger vessels, but those it does hit take a single 30 point
hit to a location that is automatically breached if they don't have Harjel, ignoring the effects of a Harjel Liner. In the event
that they do have Harjel, a breach roll occurs at a -3/-2/-1 to the target Breach to-hit number for Harjel/II/III. (A
location with Harjel is then breached on a 10-3=7+, for example.). Specialty armor has no effect.
Cost is 2x that of a normal Arrow IV warhead, with the tech rating of F and E for the IS and Clans, respectively, and with
availability ratings of F for both.

Trident IV Kraken Ammo
Functionally identical to the Davy Crockett-M Ammo, but underwater. (NOTE: That means it's a nuke and you shouldn't
leave it lying around casually on the weapons floor)
HARJEL LINERS

Not to be confused with the Battlemech HarJel Systems or the HarJel Repair Systems, Harjel Liners are cheaper, more weight-efficient ways to provide some resilience against weapon-caused breaches, which can greatly improve the survivability of surface vehicles, submarines, and Battlemechs from all angles, while only using a fraction of the HarJel that the full-strength Battlemech system uses. However, since its quantity of HarJel is fairly low, the probability of catastrophic failure of a component is negligible and the cockpit location can be (and is) protected by it.

HarJel Liners don't stack with each other but they can be combined with HarJel Repair systems or regular HarJel if desired (ex: 1 HarJel in CT to guarantee protection against breaches against the CT location while also mounting a Lightweight Harjel Liner to provide general resilience against hull breaches). Also note that HarJel Liners don't prevent breach rolls like regular Harjel, and just makes them harder, and the liners themselves do nothing to affect crush depth-related rolls, unlike Harjel and Harjel II/III.

HarJel Liners cannot be pod-mounted.

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Lightweight Harjel Liner
60,000 C-Bills
Tech Base Availability: All
Tech/Availability: D/X-X-E-D
Prototype:3060
Production:3100
Weight: .5 tons
Crits: 1 (CT) on Battlemechs, Body on vehicles
Effects: The Harjel Liner provides a thin membrane of Harjel throughout the vehicle or Battlemech, making the target
vehicle slightly more resilient against weapon-caused breaches. (+1 to hull breach TN). Note that this effectively makes
surface craft immune to surface-based breaches and require hits from below to kill by breach.
A critical hit to the liner doesn't flood locations, rather the low quantity of HarJel "bleeds out" of the chassis into the
environment, rendering the system useless against further breach rolls but otherwise leaving components unharmed.

(Standard) Harjel Liner
150,000 C-Bills
Tech Base Availability: All
Tech/Availability: E/X-X-E-D
Prototype: 3065
Production:3105
Weight: 1.5 tons
Crits: 3 (1 per torso) on Battlemechs, Body on vehicles
Effect:The Harjel Liner provides a modest membrane of Harjel throughout the vehicle or Battlemech, making the target
vehicle more resilient against weapon-caused breaches. (+2 to hull breach TN).
A critical hit to the liner doesn't flood locations, rather the low quantity of HarJel "bleeds out" of the chassis into the
environment, rendering the system useless against further breach rolls but otherwise leaving components unharmed.

Heavy-Duty Harjel Liner
270,000 C-Bills
Tech Base Availability: Clan Only
Tech/Availability: E/X-X-F-E
Prototype: 3080
Production:3120
Weight: 2.5 tons
Crits: 5 (1 CT, 2 per side torso) on Battlemechs, Body on vehicles
Effects:The Harjel Liner provides a substantial membrane of Harjel throughout the vehicle or Battlemech, making the
target vehicle more resilient against weapon-caused breaches. (+3 to hull breach TN). Note that this effectively makes a
vehicle or Battlemech immune to hull breaches from most weapons, at low depths.
A critical hit to the liner doesn't flood locations, rather the low(ish) quantity of HarJel "bleeds out" of the chassis into the
environment, rendering the system useless against further breach rolls but otherwise leaving components unharmed.
Fluff-wise, the Heavy-Duty liner uses the maximum amount of HarJel that can be safely put in a location without causing
issues on a critical hit; Any more HarJel and you'll effectively have a copy of the Battlemech HarJel system.  The Clans
save the Heavy-Duty liners for themselves making it very difficult to get by IS powers.  Clans use the heavy-duty liner on
naval designs and specialized exotic-environmentally specialized Omnimechs.
NAVALIZED ACTIVE PROBES

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NAVALIZED ACTIVE PROBES
Under normal circumstances, an Active Probe cannot detect hidden units underwater. However, any active probe or
sensor device can be "navalized" allowing them to pass through the water surface hexes and detect hidden units
underwater. If playing a double-blind match, this also allows VTOL and Aircraft (or other vehicle) probe sensors to detect
underwater units (otherwise, the sensor cannot pass through the surface of a water hex). Navalizing an active probe
increases its C-Bill cost by 50%, and its tech rating/availability rating by era is assumed to increase by one level. (Ex:The
Navalized Beagle Active Probe (N-BAP) has a cost of 300,000 C-Bills with a tech/availability rating of F/F-X-E-D). Such
equipment is basically a necessity for anti-submarine aircraft or VTOLs.

DEPTH CHARGE LAUNCHER
Depth Charge Launchers lob explosive balls underneath the surface to explode near a submarine, damaging and hopefully breaching the submarine. Although large-scale naval combat is a thing of the past, the existence of underwater assets, the occasional submarine, and the cheapness and simplicity of depth charges keeps them in use.

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Standard Depth Charge Launcher
10,000 C-Bills
Tech Base Availability:All
Tech/Availability: B/B-B-B-B
Weight:5 tons (4 Clan)
Crits: 2
Heat:0

Standard Charge: 4/ton (2000 C-Bills/ton)
Damage: 1 Capital (10)
Tech/Availability: B/B-B-B-B
Notes:The Standard Depth Charge Launcher is a basic, reloadable depth charge holding rack and uses a variant of the
Torpedo Bomb as its ammunition, so the Standard Depth Charge Launcher functions just like a bomber making a Torpedo
Bomb Run, except a ground unit using Depth charges can also make other weapon attacks too.
An Aerospace Fighter or Small Craft does a "depth charge run" the usual way Aeros do.
Hovercraft/WiGEs/Hydrofoils/Surfacecraft/VTOLs/Jumping'Mechs/Whathaveyou do Depth Charge runs as though they
were VTOLs making a bombing run (as per Tac Ops Pg.107ish), except they can fire their other guns at other targets as
well.

Barrage Charge: 4/ton (3500 C-Bills/ton)
Tech/Availability: C/B-C-C-B
Damage: 2/cluster (5 clusters)
Notes: Barrage Charge Ammo is an alternative type for the Depth Charge Launcher, operating similar to the standard
Depth Charge ammo (and torpedo bombs) but without the +1 modifier to the breach roll, and fires 1 container that splits
into 5 smaller charges. On a successful to-hit roll, the Barrage Charge rolls on the 5 column of the cluster hits table on
the in an attempt to cause a hull breach by sheer number of hits. Since it fires a barrage of charges it's more likely to get
a at least some hits, giving a bonus -1 to the to-hit number.

"Sea-Monster" Charge: 1/ton (5000 C-Bills/ton)
Tech/Availability: C/C-D-D-C
Damage: 4 Capital (40)
Notes:The "Sea Monster" is an alternative type for the Depth Charge Launcher based on the torpedo launcher's rules
with a few exceptions, and is one of the lowest-tech methods of killing large submarines, and can still be effective even
against basic HarJel Linings due to its powerful punch. While the Sea Monster is very unwieldy (Inherent +2 to-hit with
an additional +2 to-hit for targets under 500 tons), the sheer damage can destroy small submarines with one hit, and
the Sea Monster hits with such force that it causes an automatic roll on the critical hit table. In addition, the Sea Monster
applies a +5 modifier (instead of +1) to the subsequent Breach roll, often making breaches more likely than not even
against HarJel Linings (though the Battlemech HarJel System and above still stops breach checks).

"Radioactive Sea-Monster" Charge: 1/ton (500,000 C-Bills/ton)
Tech/Availability: E/F-F(F*)-F-F
Notes: The Radioactive Sea Monster is basically a depth charge version of the Davy Crockett Ammo, put on a
customizable timer and hovers around and explodes at Depth 50 once the timer runs up.

Depth Charge Catapult
15,000 C-Bills
Tech Base Availability: All
Tech/Availability: B/C-C-C-C
Weight: 7 tons (6 clan)
Crits: 4
Heat: 0
A slightly more powerful version of the Depth Charge Launcher, the Depth Charge Catapult can actually throw the charge
a decent distance away from the vehicle for a slightly longer reach. In addition to being able to drop depth charges as
though doing a bombing run, the Catapult has a range of 2/4/6 for standard/barrage charges, and 1/2/3 for Sea
Monsters, with an extra +2 to-hit modifier added (in other words, throwing the charge is no more accurate than merely
dropping the charge.). However, VTOLs and Aerospace units cannot use the Depth Charge Catapult.

'MECH MORTAR "HEDGEHOG" AMMO

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Costs, Availability, tech rating etc: Same as 'Mech Mortar Shaped Charge ammo
Description: The 'Mech Mortar can be re-armed to make a cheap way to threaten submarines on shallow waters. The
Hedgehog Ammo uses the Shaped Charge warhead but modifies the fuse such that it doesn't blow up upon impacting the
water. Units with the "Hedgehog" can target and attack submarines up to Depth 21 as per normal 'Mech Mortar Shaped
Charge rules. Against anything not underwater, Hedgehog ammo only deals half damage.
In the case of the Mech Mortar '8, the Mortar can fire in "Diamond Pattern" mode, adding a -3 to-hit modifier at the cost
of a hefty -5 modifier to the cluster hits table
ANTI-SHIP MISSILES
Anti-ship missiles are a proven, effective way of accurately hitting and knocking out other ships. While they're virtually
never used in that role since the Space Age due to lack of other naval forces in the invader's fleet, and can be foiled by
dedicated AMS layering, ASMs continue to be used on water-rich worlds as they happen to be quite effective against
grounded Dropships.
Modern-Day ASMs are based off of Space-faring Capital & Sub-Capital Missiles. Redesigning them to use in an
atmosphere and removing/redesigning the computer targeting systems and high-peformance vector thrusters for tracking targets moving at thousands upon thousands of m/s allows for far cheaper, easier to obtain, and lighter missiles.

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General Rules:

The Technology/Availability Rating of an ASM version is one step lower than its space-based equivalent (Ex: Tech rating E
Killer Whale -> Tech rating D Killer Whale ASM). The C-Bill cost of the missiles is 1/2th of its space-based equivalent &
weight of one missile is half that of its space-based equivalent (Ex: Killer Whale ASM weighs 25 tons, costs 10,000 C-
Bills)

ASMs can only target buildings, mobile structures, and ground units. It targets the unit specifically, not the hex it's in,
and can do so as long as any friendly unit can visually see the target. If playing in double blind mode one can choose to
fire at an unknown target that's spotted by sensors, though the firing player will not be told what he just targeted by the
GM.

An ASM has a range in ground mapsheets equal to its space equivalent's max extreme range on the expanded capital
ranges table. Ex: a Killer Whale has a range of 48 mapsheets, and a Manta Ray has a range of 9 Mapsheets.

The ASM hits its target in the same # of turns that a Cruise missile takes: RoundDown(1+# Mapsheets Away/5), with
map sheets measured between the two vehicles at the time of firing for simplicity.

Advanced ASM Travel Times Table
The rules above assume that all missiles travel at the same average velocity, but some ASMs may travel slightly faster or
slower than others. Use the table and Equation below to determine the # of turns for specific missile types.
# Turns=RoundDown(1+# Mapsheets Away/(5+X+Y))

Missile Class X=
Capital 1
Sub-Capital -1

Missile Type Y=
Barracuda 1
Killer Whale -1
Piranha 1
Manta Ray -1

Ex:Under these rules a Barracuda Capital ASM will have a turn formula of RoundDown(1+#Maps/7)
Under these rules a Manta Ray Sub-Capital ASM will have a turn formula of RoundDown(1+#Maps/3)

The THN of an ASM strike=Base Gunnery + Target Movement Modifier + 3 (Base ASM inaccuracy) + 4 (If target is 100
tons or less)+Misc. ASMs automatically miss all airborne targets except Airships, and applies an additional +4 penalty to
target them. ASMs are not affected by terrain effects like woods.

Capital and sub-capital ASMs get the same extra crit chance as their space-based equivalents.

Additionally, Sub-Cap and Capital Missiles have the following bonuses to breach checks:
-Capital ASMs reduce the target breach number by -2, sub-capitals by -1
-ASMs ignore the effects of HarJel Liners
-ASMs still roll for breaches against locations protected by regular HarJel, at a penalty of +1/+2/+3 to the target breach number.

Successful ASM hits can be engaged by defense systems in a similar manner that Warship AMS can interact with Capital Missiles.
SURFACE-TO-AIR CAPITAL MISSILES
SAMs are an old technology used to create a long-range safety net against VTOLs and Aerospace Fighters, small craft, or Dropships daring enough to fly nearby. While the missiles themselves are heavy, their power and range eclipses that of the venerable Arrow IV, and some versions can even be used as an Anti-Missile System.

Modern-Day AAMs are based off of Space-faring Capital & Sub-Capital Missiles. Redesigning them to exclusive use in an atmosphere and lowering its fuel capacity somewhat allows for cheaper, easier to obtain, and lighter missiles.

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General Rules:

The Technology/Availability Rating of a SAM version is one step lower than its space-based equivalent (ex:Tech Rating E
Barracuda -> Tech Rating D Barracuda SAM). The C-Bill cost of the missiles is 1/2th its space-based equivalent and the
weight of a SAM is 1/3rd its space-based equivalent, rounded up (ex: Barracuda SAM costs 4,000 C-Bills and weighs 10
tons).

SAMs can target airborne units only. If playing in double blind mode, the player may fire at a unit that is visually spotted
or just detected by sensors, but automatically misses if the unit is not airborne.

Attacks made by a SAM Capital Missile are resolved as if they were making Arrow IV ADA attacks, with the following
exceptions:

The range brackets, in terms of hexsheets, are determined by the ranges of the missile's space-borne equivalent on the
sarna wiki (Which is from Strat Ops's Individual Weapon Ranges rules table on pg 115) divided by 2, rounded up. Ex:
The Barracuda's range brackets on the Detailed Ranges Table are 1-20 short, 21-30 medium, 31-40 long, 41-50
extreme. The Barracuda SAM would have a range in ground mapsheets of 1-10 short, 11-15 medium, 16-20 long, 21-25
extreme.
Ex: The Manta Ray's brackets on that same table are 1-3 short, 4-5 medium, 6-7 long, 8-9 extreme. The Manta Ray SAM
would have range in ground mapsheets of 1-2 short, 3 medium, 4 long, 5 extreme

The Barracuda and Piranha SAM gets a -1 to-hit modifier in attacks

Capital and sub-capital SAMs get the same extra critical hit chance as their space-based equivalents.

SAMs that aren't fired in a turn can be used in an anti-ASM action, with details to be described later.

SAMs can be defended against by a Dropship's point-defense systems in the same manner as an equivalent Capital
Missile or Sub-Capital Missile strike.

CAPITAL TORPEDOS
Modern large-scale torpedos are based off of capital & sub-capital missiles, and modern guided torpedos are theoretically capable of scoring a deadly hit on a large naval vessel from thousands of meters away, but are almost never actually used in combat: A scenario involving ships is rare enough, but ship-to-ship confrontations is unheard of outside of obscure trivia.

While theoretically better able at causing breaches than ASMs or surface-fired capital weapons, and while torpedos are fairly cheap, ships utilizing Capital Torpedo do so more out of tradition than out of any sort of military need.

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General Rules:

The Technology/Availability Rating of a torpedo version is two steps lower than its space-based equivalent (Ex: Tech
rating E Killer Whale -> Tech rating C Killer Whale torpedo). The C-Bill cost of the missiles is 1/4th of its space-based
equivalent & weight of one missile is a third that of its space-based equivalent, rounded up to the nearest half-ton (Ex:
Killer Whale ASM weighs 17 tons, costs 5,000 C-Bills)

Torpedos target units under the surface of the water. If playing in double blind mode one can choose to fire at a target
detected by sensors, though the player will not be told by the GM what he just targeted.

A Capital Torpedo travels underwater at the rate of 3 hexsheets per turn, while sub-capital torpedos travel at 2 hexsheets
per turn, and either has a maximum range in terms of mapsheets equal to its max range on the strat ops individual
ranges table divided by 3, rounded up. Ex: a Manta Ray has an extreme range of 9, so a Manta Ray torpedo would have
a range of 9/3=3 Mapsheets. Ex: A Barracuda has an extreme range of 50, so a Barracuda Torpedo has a range of
50/3=17 Mapsheets. For simplicity's sake measure the time it will take for the torpedo to hit the target at the time of
firing, ignore if the target moving closer or further away from the target would result in longer or shorter transit times.

The THN of a Torpedo strike=Base Gunnery + Target Movement Modifier + 3 (Base ASM inaccuracy) + Terrain Effects
(but not intervening terrain) + 4 (If target is 500 tons or less)+Misc.

Capital and sub-capital torpedos get the same extra crit chance as their space-based equivalents.

Additionally, Sub-Cap and Capital Torpedos have the following bonuses to breach checks:
-Cap & Sub-Cap Torpedos have breaching characteristics like the Trident IV Scylla Ammo
-Against targets with HarJel proper, Sub-Capital torpedos have a +1 penalty to the breach target number, making it harder to breach relative to capital torpedos.

Capital Torpedos can be engaged by point-defense AMS in the same manner as Warship CIWS engaging capital missiles,
but since they approach from underwater they're immune to fire by ballistic-based AMS.

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(I hit the character limit for that post, which is apparently 2^15 characters.  Didn't even realize there was one!)

LAUNCHING PLATFORMS FOR TORPEDOS, ASMs, & SAMs

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Non-Ship Based: Vehicles, VTOLs, Fighter, Small Craft

Ground Vehicles, Mechs, VTOLs, Fighters, Dropships & Small Craft can all carry Torpedo, ASM, and SAM versions of
Capital Missiles in One-Shot mounts, which weighs and costs the same amount as just the missile itself. Vehicles &
Aerospace Fighters require 1 slot for the weapon, while a torpedo/ASM/SAM version of a capital torpedo takes up a
number of crits equal to the missile/torpedo's tonnage/2, rounded up. Note that heat tracking units like Aerospace
Fighters and Battlemechs still need to sink the heat generated by the weaponry, determined from their space-based
equivalents
Ex: A White Shark ASM weighs 20 tons, so it'd take 10 crit slots on a Battlemech mount. Firing that missile would
produce 15 heat.
Ex:A Barracuda SAM weighs 10 tons, so it'd take 5 crit slots on a Battlemech mount. Firing that missile would produce 10
heat.

Alternatively, Aerospace Fighters, Convfighters, and VTOLs (under Tac Ops Rules) can use the missiles as external
munitions using their hardpoints. When used in this faction Aeros don't need to track the heat produced by the missiles,
though they'll slow down the vehicle as per usual hardpoint rules. The space they take up in terms of hardpoints is equal
to their weight in tons, so a 10-ton Barracuda SAM (or, well, AAM in this case) takes up 10 hardpoints, or a 20-ton White
Shark takes up 20 hardpoints. Note that this basically means that Aerospace fighters, ConvFighters and especially VTOLs
are generally limited to the smaller, sub-capital variants when mounting missiles and torpedos via the hardpoint system.

Aerospace Fighters, ConvFighters, Small Craft, and Dropships, if they have a cargo bay and the Internal Bomb Bay quirk,
can also mount Torpedos, SAMs and ASMs as "bombs".

Large-scale wet navy vehicles can theoretically also use one-shot mounts. However, since they take up 1 Capital Crit Slot
per one-shot missile, this tends to be restricted to patrol boats and corvettes that are limited in tonnage anyways.

Large Naval Vessel-type launchers

ASM Launcher
ASM launchers have half the weight and C-Bill cost of their space-based equivalents, and have technology and availability
ratings 1 level less than their space-based equivalents.
Ex: The Killer Whale ASM Launcher weighs 75 tons, costs 75,000 C-Bills, and have tech/availability ratings of D/B-D(E)-D-C

The sole exception is the AR-10 ASM Launcher: It has half the weight and C-Bill cost of their space-based equivalents,
but has the same availability ratings as their space based equivalent.

AR-5 ASM Launcher
The AR-5 is basically a sub-capital version of the AR-10 introduced in 3075. Weight is the same as the AR-10. Its
tech/availability rating is the same as the AR-10, except for pre-3075 when it doesn't exist yet.

Universal ASM Launcher
The Universal Missile Launcher was introduced in 3100 and combines the AR-5 and AR-10 systems. It has a tech rating of
F and availability rating of F, with a weight of 300 tons and a C-Bill cost of 350,000.

The Universal ASM Launcher, specifically, weighs 150 tons and costs 175,000 C-Bills, with the same tech rating and
availability rating as it's space-based counterpart.

SAM Launcher
Same as ASM launcher, but fires SAMs

AR-10 SAM Launcher
Same as AR-10 ASM launcher, but fires SAMs

AR-5 SAM Launcher
Same as AR-5 ASM launcher, but fires SAMs

Universal SAM Launcher
Same as Universal ASM Launcher, but fires SAMs

Omni-Launcher
An Omni-Launcher is capable of firing ASMs, SAMs, and the Space-Based variant of the Capital or Sub-Capital Missile
(Including Tele-Operated versions). It weighs 50% more than the space-based launcher, and the C-Bill cost is twice that
of the base launcher. It's primarily used on wet navy vessels but it could theoretically be mounted on Dropships,
although the ASMs and SAMs would be useless in space.
Ex:An Omni-Piranha Missile Launcher weighs 150 tons and costs 150,000 C-Bills.
Ex:An Omni-Universal Launcher weighs 450 tons and has a C-Bill cost of 700,000.

Barrage-6 Launcher
Only regular ASMs can be modified as a Barrage-6 Launcher. Omni-Launchers, AR-10s, AR-5s, and Universal ASM
Launchers cannot. Weight is 5x of a regular ASM launcher and 8x the C-Bill cost. Barrage-6 Launchers fire a stream 6
ASMs in one turn in an effort to overwhelm AMS, but requires nearly a minute to reload (Can fire once every 6 turns).
Chief advantages include slightly lower weight than 6 regular launchers, substantial "alpha-strike" capability for
overwhelming AMS, and still only requiring 1 capital-scale crit slot.
Ex:The Space-based Manta-Ray launcher weighs 160 tons and costs 150,000 C-Bills.
So a Manta-Ray ASM Launcher weighs 80 tons and costs 75,000 C-Bills.
A Barrage-6 Manta Ray ASM Launcher, then, weighs 400 tons and costs 600,000 C-Bills.

Torpedo Launcher
Torpedo Launchers have half the weight and C-Bill cost of their space-based equivalents. The technology & availability
rating of a launcher is two steps lower than its space-based equivalent.

Only regular capital missile launchers can be a torpedo launcher. AR-10s and AR-5s cannot.
OTHER CAPITAL/SUBCAPITAL WEAPONS ON NAVAL VESSELS
Not really new weapons, these rules just expand the range of abilities for naval-mounted capital and sub-capital weaponry.

Code: [Select]

-Naval weapons can make surface-to-orbit attacks in the manner outlined in Strategic Operations pg.109
-Capital/Subcapital missiles can make surface-to-surface attacks in the manner outlined in Strategic Operations.
-Naval Autocannons and Naval Gauss rifles mounted on blue water vessels are specifically modified with the capability of
making low-power shots capable of performing indirect fire like an artillery gun to support planetside garrisons with long-
range artillery support and to give another threat to dropships, and use a modified version of the Artillery Rules
-Capital ballistic weapons firing on the ground map can make an attack every 6 turns. Sub-capital ballistic weapons can
make an attack every 3 turns.
-Capital ballistic weapons can make direct fire attacks using their space equivalent's range brackets in hexes. The attack
is made as if it were making a direct-fire artillery attack.
Ex: A Light Naval Gauss Rifle would have the range brackets of 14/28/40/56 when firing directly.
-Capital ballistic weapons making indirect attacks use the table below to determine flight time in terms of ground turns:

INDIRECT FIRE CAPITAL CANNON ARTILLERY TABLE
Distance Flight Time*
(Hexsheets) (Turns)
<1 0
1-16 1
17-30 2
31-42 3
43-52 4
53-60 5
*For Naval Gauss, divide flight time by 2 and round up to get their flight time.

-The maximum indirect range of a capital weapon in hexsheets is determined by their space-based equivalent's extreme-
range direct-fire brackets. Ex: A Light Naval Gauss Rifle has a max range of 56 hexes.
-Naval ballistic weapons suffer additional to-hit modifiers during indirect fire based off their firing range that other
artillery weapons don't suffer from: +0 at short, +1 at medium, +2 at long, +3 at extreme.
Ex: a Light Gauss Rifle (range brackets 14/28/40/56) firing 10 mapsheets out would suffer from no penalty, but if firing
out to 40 hexes suffers a +2 extra penalty.
Ex: a Heavy Sub-Capital Cannon (range brackets 5/10/15/20) firing 10 mapsheets out would suffer from a +1 penalty,
and firing 20 mapsheets out would suffer from a +3 penalty.
-Naval lasers and PPCs still can't do surface-to-surface indirect fire for obvious reasons. However, they can still do direct-
fire attacks in the same manner as capital ballistic weapons.

HARDPOINT-MOUNTED SEARCHLIGHT

Code: [Select]

ConvFighters, Aerospace Fighters, and VTOLs under tac-ops rules can use a hardpoint to mount a Mounted
Searchlight as "external ordnance".  It uses all the normal rules of a Mounted Searchlight but uses the front/nose arc as
its housing location for determining whether to roll for its destruction on a hit.

[Alsadius]

Most of that is fairly straightforward, but it's all eminently logical.

I'd be more inclined to tweak construction rules a bit, so that we can have something bigger than a speedboat out there on the water(IMO, just adapt the WarShip rules in their entirety as a starting point), but for weaponry options that's all quite good.

[Charistoph]

Surface navy ships are rather impractical when you have dropships and otherwise cheap aerospace transports.  Let's face it, even a Union would be painful for a Frigate to face, if you have an Assault Dropship, they and any aerospace assets would consider anything larger as easy prey.

Usually brown naval operating Combat Vehicles have much common practicality.  They can deliver artillery to places that would only be otherwise accessible by VTOL, hovercraft, WiGE, and Mech.

Subsurface naval assets are a different story, but only when you have subsurface operations and communities on a world to justify their use.

Still, all and all, it would be surprising to not have the scale of weaponry you are proposing.

[Retry]

Most of that is fairly straightforward, but it's all eminently logical.

I'd be more inclined to tweak construction rules a bit, so that we can have something bigger than a speedboat out there on the water(IMO, just adapt the WarShip rules in their entirety as a starting point), but for weaponry options that's all quite good.

I was thinking about adapting construction rules for combat naval vessels as well, and that was what I was thinking about when developing the rules for ASMs, SAMs, Capital Torpedos, & the expanded capabilities of sub-capital ballistic weapons.  Had issues doing it myself though adapting warship rules would be good to start with.

Surface navy ships are rather impractical when you have dropships and otherwise cheap aerospace transports.  Let's face it, even a Union would be painful for a Frigate to face, if you have an Assault Dropship, they and any aerospace assets would consider anything larger as easy prey.

Usually brown naval operating Combat Vehicles have much common practicality.  They can deliver artillery to places that would only be otherwise accessible by VTOL, hovercraft, WiGE, and Mech.

Subsurface naval assets are a different story, but only when you have subsurface operations and communities on a world to justify their use.

Still, all and all, it would be surprising to not have the scale of weaponry you are proposing.

I see your point, but dropships aren't cheap.  Three union pocket warships are nearly a Billion C-Bills, and have a few spheroid-related maneuvering issues in an atmosphere.  A 'cheap' 400-ton Vampire costs well over a hundred thousand C-Bills.

Small craft and Aerospace fighters are cheaper but often they're even less common than a Battlemech, unfortunately.  ConvFighters definitely are cheap and plentiful, I've not heard of them being used in an offensive though.

I was originally planning on a more detailed in-depth missile interception game (AC/2s and AC/5s able to participate in anti-capital missile fire as some sort of giant RISC system, anti-ASM firing modes for some large guns, SAMs operating as anti-ASM missiles, etc), that was scrapped for a short term to use the existing system for simplicity's sake.

Mix a few FFs with a NL or SCL + a few token capital missile-type systems and a few DDs with NPPCs and some capital missile type systems, sprinkle around some VTOLs between them, base it around a (preferably) submersible carrier, and you've got yourself a nifty little planetary task force.  It won't fend off a house's Grand Fleet but it'll scare off Pirate Jumpships from getting too close, keep Overlords from getting familiar with the surface for too long, and even a Corvette will have reason to pause.

Also the idea of Naval cruisers exchanging fire with Foxs is really cool

[Starfox1701]

Considering the fact that modern battleships mass as much as drop ships its worth looking into.

[Alsadius]

Something the size of a modern aircraft carrier could easily challenge a DropShip or two - just think of it as a mobile Castle Brian. If it's submersible, it could even hide when unfriendlies are in orbit.

Imagine a modern nuclear missile submarine, but game-rule it that the missiles are White Sharks instead of Tridents(which weigh 33 tons, so it's quite plausible). One salvo will kill almost any DropShip, and noticeably degrade the combat abilities of a WarShip, even with conventional warheads. Use nukes, and you can challenge a whole invasion fleet.

[I am Belch II]

Nice job. It would make some of the Naval SHips and the Support Ships that were made some actual firepower to be useful.

[idea weenie]

Imagine a modern nuclear missile submarine, but game-rule it that the missiles are White Sharks instead of Tridents(which weigh 33 tons, so it's quite plausible). One salvo will kill almost any DropShip, and noticeably degrade the combat abilities of a WarShip, even with conventional warheads. Use nukes, and you can challenge a whole invasion fleet.

I'd want some way to launch the missiles while remaining underwater (similar to the Trident).  It would likely be a tonnage increase for both launcher and ammo, but it also means that orbital assets have to go down and deal with the missile chunking pest via orbitally deployed depth charges/munitions.  Otherwise if the sub has to surface to fire, that makes it very vulnerable to return fire.

For the Original Post, what could be useful is rocket-launched ordnance, such as rocket-launched torpedoes.  Rockets can get a higher speed in atmosphere than torpedoes underwater, so the net effect would be to give them a longer range than torpedoes.  They would of course be larger (due to needing a rocket engine and parachute to softly drop the torp), can only be launched by targets that are surfaced, but the range means any sub that is detected will soon have lots of little splashes overhead.

[Retry]

I'd want some way to launch the missiles while remaining underwater (similar to the Trident).  It would likely be a tonnage increase for both launcher and ammo, but it also means that orbital assets have to go down and deal with the missile chunking pest via orbitally deployed depth charges/munitions.  Otherwise if the sub has to surface to fire, that makes it very vulnerable to return fire.

For the Original Post, what could be useful is rocket-launched ordnance, such as rocket-launched torpedoes.  Rockets can get a higher speed in atmosphere than torpedoes underwater, so the net effect would be to give them a longer range than torpedoes.  They would of course be larger (due to needing a rocket engine and parachute to softly drop the torp), can only be launched by targets that are surfaced, but the range means any sub that is detected will soon have lots of little splashes overhead.

I think rules for firing capital missiles or cruise missiles while underwater already exist somewhere.

Rocket-launched torpedo ordnance is an interesting idea.  I'm a bit exhausted after doing this and the more recent artillery expansion, so maybe I'll work on that later.