40mm Swift Mini-missiles and DGLs

DGLs are one-use, usually one-shot disposable grenade launchers. They can be used alone but are generally attached to a mounting such as the accessory rail of a rifle. Originally used for grenades and shotgun-like loadings they are now often encountered loaded with 40mm mini-missiles such as the ILCAS-40 Swift series. The Swift series was designed to engage personnel, cybershells, obstacles such as machine gun positions and lightly armoured vehicles.

Most DGL launchers use high-low pressure mechanisms, spigot configurations and captive pistons to achieve a flashless and low-noise launch signature. Mini-missiles are soft-launched, the rocket igniting and accelerating the round several yards beyond the muzzle. The launchers are constructed from lightweight alloys and polymers. Typically they have a small folding grip that protects the trigger. They can also be fired electrically.

 

        DGL munitions can be used in a number of ways:

·         They can be attached to weapon accessory rails to serve as underbarrel or sidebarrel launchers. Military users often reserve space on a rail for one or two DGLs to be fitted and carry additional reload DGLs. If the weapon has suitable fire control it can program fuse settings.

 

·         DGLs may also be mounted directly on power armour, battlesuits or cybershells. Many military vehicles mount clusters of DGLs for smoke screening or local defence.

·         Many vehicles use DGLs offensively mounted in armoured boxes to give an intermediate level of force between machine guns and main weapons. Crew-served and vehicle-mounted weapons either mount DGLs on the weapon or on brackets on the mounting or tripod. A machine gunner, for example, can fire mini-missiles to airburst over enemies he has driven into cover.

·         Multiple DGLs can be fitted to small baseplates mounting between three and twelve launchers. Each mounting is adjustable to vary aim and elevation. Such systems are used for area defence, illumination and for ambushes.

·         The “Six-shooter” is a dedicated grenade launcher that mounts up to six DGLs on a stock with a fire control system. A bipod may be fitted to this system. A simpler, more compact launcher mounts just two DGLs. Some platoon leaders favour a double barrelled 20mm micro-missile launcher with a rail and FCS for a DGL.

40mm Mini-Missiles.

 40mm mini-missiles are an alternative to 30mm systems. They are designed for high-subsonic velocities, giving them an advantage over the supersonic 30mm mini-missiles in both range and capacity. A DGL launch tube weighs 2.2lbs and contains a single 40mm mini-missile.

The first 40mm mini-missiles were fielded in the early half of the 21^st century. They took the form of unguided rounds that were stabilized so that they would fly in a straight line, compensating for the effects of wind and drop. As technology advanced laser-homing and then homing mini-missiles variants became more common. The Swift mini-missile is steered by a combination of thrust vectoring and a gimballed nose-cone.

From the start mini-missiles were designed to use programmable fusing. The shooter lased the distance to the target and the missile was programmed to detonate at a certain distance. The fire control system (FCS) would also track target speed and direction and provide the shooter with a corrected point of aim. Initially mini-missiles were used with dedicated “Grenadier” model rifles fitted with a fire control system that could program the fuse system. If used without such as system they defaulted to stabilized, impact-fused munitions. By 2100 fire control systems have become so compact and cheap that most Fourth and Fifth wave military rifles, SMGs and machine guns have them fitted as standard.

The flat, straight trajectory of the mini-missile allows an engagement range in excess of 1,300 yards. Average velocity is 295 yards per second. 40mm mini-missiles have an arming distance of 10 yards (5 if a HEAP/ shrapnel round set to “cone”). If they hit a target within this arming distance they will not detonate. Since they have not yet accelerated to full velocity they will only do 2d cr damage.

Below are a selection of the more common or more interesting DGL and 40mm mini-missile loads. Transhuman Space technology such as minifacts or 3D printing make it feasible that alternate rounds can be created. As a guide, a 40mm mini-missile has a capacity of about half a pound of explosive, or twice that of a modern 40x46mm grenade round. This is also the likely capacity of a DGL grenade round. Treat these non-mini-missile rounds as having a similar size and range to a rifle-grenade.

Weapon	Damage	Acc	Velocity	Range	Weight	RoF	Shots	ST	Bulk	Rcl
Swift 40mm mini-missile	Variable, see text below.	2	295	10-1300	2.2	1	1(4)	10†	-	2

 

High Explosive Multi-Purpose.
        HEMP is now the commonest configuration of 40mm mini-missile in use. It is a directional penetrating warhead with area explosive and fragmentation effects. The smart fuse has the following options:

• Impact: This is the default mode should the fuse not be programmed for some reason. It is also used for direct attack against well protected targets. In actual fact the fuse sensor explodes the round slightly before impact for optimum explosive penetration effect. Damage 6d x 5(10) cr + linked 3d cr ex [1d+4]. Main (non-explosive) damage in all cases is incendiary (see p. B105). Blast radius 6 yards, fragmentation radius 5 yards.
• Airburst: The firer lases the distance to a target and the round is automatically set to explode when it reaches this distance. Treat as an airburst, 3d cr ex [1d+4], blast radius 6 yards, Fragmentation radius 10 yards unless something is in front of the round within the effect area. In that case the object or person also takes 6d x 5(10) cr from the shaped-charge effect.
• “Window”: The round explodes 1.5 yds beyond the lased distance. This lets the round fly though an opening and explode within a room or just beyond a wall it is fired over. Treat as an airburst, 3d cr ex [1d+4] blast radius 6 yards, fragmentation radius 5 yards.  
• Delay: Allows the round to punch through light cover or vegetation before detonating. Use 6d (0.5) cr verses any resistance. Treat as a normal impact or airburst detonation if it penetrates cover or comes to a stop.

High Explosive Anti-Personnel.
        HEAP was once the most widely used form of 40mm mini-missiles. It is still often issued in conflicts where cybershells and battlesuits are relatively rare and the usual targets are humans or bioroids. It was formerly common practice to use HEAP for most shots, keeping HEMP loads until a suitable target presented itself or all the HEAP had been used.
        The round is programmed to explode at a set distance from its firer. It can be set to “Window” or “Delay” modes like the HEDP variant. If for some reason the round does not get programmed it defaults to impact detonation with a cylindrical blast pattern.
          HEAP is effectively a shrapnel round. To be more accurate, it is a modern version of the Krupp Universal Shell. Steel balls are packed around a rod of explosive with an ejector charge at the base. The round casing is prefragmented. The HEAP rocket has two modes, depending on whether the ejector charge or the central bursting charge is triggered. If the main central charge is detonated the round scatters shrapnel and casing fragments in a roughly cylindrical pattern. Treat as a rectangular airburst 10 yards to each side and 4 yards to front and rear. 7d cr ex [2d+1]. This counts as an airburst attack to an area (+4). On a miss use scatter rules (p.B414) to find where the round ejects its shrapnel. Shrapnel is ejected in the opposite direction of a line drawn from the ejection point and the firer.
          When the basal ejector charge is triggered the round behaves like a flying claymore mine or a blast of grapeshot that forms a 30 degree cone, 1 hex wide at its origin, 3 hexes wide at 6 yards. The round is usually targeted and programmed to eject in a hex 7 yards ahead of the intended target. Treat range of cone blast as 30/600 and damage as 1d-1(0.5) pi. The round contains 100 balls so treat as +7 bonus to hit against any targets in the cone. Range modifiers for the shrapnel load are from the hex the round ejected in, so potential targets 7 yards away are -3.

SEFOP.
        The 40mm SEFOP warheads are only available for homing projectiles. They are fired to overfly the target and may be set to either attack the side they are facing or the top, targeting particular hit locations (usually the head of a person or a tank turret), and ignoring cover that does not protect from above or penalties for striking prone or kneeling targets. 6d x4+20(3) cr.

Target Indicator Missile.
        Target Indicator mini-missiles begin to emit coloured smoke when 40 yards from the launcher. This continues for 12 seconds so the round will continue to emit smoke after it has impacted its target. The target it therefore marked by a column of smoke and a streamer of smoke leading towards it. More sophisticated variants use homing or laser-homing. An indicator mini-missile may also incorporate a radio locator beacon and/or an LED strobe-light for operations where the smoke is unlikely to be visible.

Tangler.
        A 40mm mini-missile with a tangler warhead will cover a 2 hex radius. A DGL loaded with a tangler grenade is likely to be less accurate and shorter ranged but have a larger capacity so will affect a 4 hex radius.

Incendiary.
        Incendiary mini-missiles are mainly used for sabotage or despoilment (destruction of supplies) so are not standard issue. Of course, in 2100 such things can be easily minifactored when needed. Incendiary missiles are likely to contain thermite or/and Thickened Pyrotechnic Agent (effectively napalm!). See “High Tech (4e)”.

Surveillance Fluff.
        The surveillance mini-missile delivers a small cloud of surveillance fluff (above) to an altitude of 2,000ft above a point up to 1,100yds distant.

DGLs with Grenade Loads.

Weapon	Damage	Acc	Velocity	Range	Weight	RoF	Shots	ST	Bulk	Rcl
DGL Grenade	Variable, see text below.	2	100	10-165	2	1	1(4)	10†	-	2

Fragmentation Grenade.
        This round is an unguided grenade rather than a mini-missile. It will detonate at a pre-set distance from the launcher, setting being applied manually some time before use (requires a screwdriver or similar). Vehicles use these rounds for local defence and set them to explode just a few yards after firing. Several may be loaded into a multiple launcher and used to bombard an area. 5d [2d] cr ex. Max range 165yards.

Smokescreen.
        This round is usually a grenade rather than a missile. Launchers loaded with such rounds often form part of the self-protection suite of vehicles and large cybershells. Infantry also use them for screening.
          The round contains 18 plastic-covered “wedges”, each containing a quantity of smoke composition. The grenade is fired so that the casing breaks up just above the intended target and the wedges are scattered over that area. A catalytic reaction causes each wedge to rapidly produce smoke resulting in a rapid, dense build-up of cloud. Grenade break up and cloud production are designed to be flameless to minimise the likelihood of unplanned fires.
          The smokescreen round is commonly available with various smoke compositions including prism and hot prism. It requires 9 doses of chemical and one grenade covers a 10 yard radius. Cloud duration 300 secs divided by windspeed in mph. Max range 165 yards. More recent versions use PFOG technology.

Screening Rifle/ Hand Grenade.
          The projectile used in the smokescreen DGL is also available as a Rifle/Hand Grenade. The Rifle/Hand Grenade can either be hand-thrown or launched from a rifle-muzzle. In the later mode it is a bullet-thru design so can be projected by standard 5mm, 5.6mm or 6.6mm combat rounds rather than specialist ammo. The smoke R/HG is often preferred to the smoke DGL due to its greater versatility. Treat as weight 1lb for throwing by hand. Rifle-launch max range 165 yards. A fragmentation version of the Rifle/Hand |Grenade is also available.

Paraflare.
        Flares are available in DGL format but generally they are hand-fired rather than weapon-mounted. The standard illumination flare is a 38mm parachute flare that illuminates a 185-yard radius for 40 seconds. If fired directly at a target at close range, before it deploys and lights, it inflicts 1d+1(0.5) cr dkb. A burning flare does 1d of burn damage every second it is in contact. Available in white, red and infra-red enhanced.

Day and Night Signal flare.
          At night is visible as a white or coloured star intended for signalling rather than illumination. The burning of the star also produces a streamer of smoke in the same colour that is more visible in daylight. An X-shaped parachute keeps the flare in the air longer and reduces the chance of the flare landing still burning. The parachute is also designed to catch in tree tops allowing personnel in woodland or jungle to signal.

Flechette.
        The flechette DGL fires multiple projectiles rather than a single grenade or missile. It is designed for close range combat, each launcher containing 160 flechettes which are fired in a 10° arc. Flechette DGLs are often used for booby traps or as command-detonated mines. A 10° arc is 3 hexes wide at 17 yards, minimum width 1 hex. Treat as a single-use shotgun. Dmg 1d-3 pi-, Acc 2, Range 100/1,200, RoF 1x160 , Rcl 1, Bonus to hit +7.

Anti-Ambush DGL.
        The anti-ambush round contains buckshot followed by a small grenade containing smoke pellets and preformed fragments. Treat as a single-use shotgun. The buckshot load does Dmg 1d-1(0.5) pi-, Acc 2, Range 30/600, RoF 1 x 20, Rcl 1, Bonus to hit +4. The grenade is fired at the same location (to a maximum of 60 yards) and does 6d cr ex [1d] and produces a 6 yard radius smoke cloud for 12 seconds.

Riot gas.
        This round uses the same components and mechanism as the smoke screening round but releases riot gas instead of smoke. The wedges scattering over a large area makes it very difficult for rioters to smoother them before the gas affects them. The flameless design features minimise collateral damage.
          A riot gas grenade requires 9 doses of chemical and one grenade covers a 10 yard radius. Cloud duration is 300 secs divided by windspeed in mph. Nanodrugs or chemicals other than riot gas may be used instead to produce other effects on the targets, for example “Cry Baby” (TS:CT p66).

Ring Aerofoil Baton (RAB).
        The RAB is a riot control munition mounted in a DGL. The ring aerofoil projectile generates lift as it flies so follows a relatively flat trajectory. It is a kinetic energy round designed to engage rioters at relatively long ranges. It is usually used to target ringleaders or particularly aggressive individuals. The RAB does Dmg 1d+1(0.5) cr dkb, Range 120. Marker dye and/or one dose of malodorant chemicals may also be included in the projectile.

Multi-Ball.
        A multiple projectile kinetic energy crowd control round for short range use. Contains a load of polymer pellets and two larger polymer balls. Intended to be fired at the legs and lower body, the weapon's AI may prevent the shooter targeting the head region. Treat as a shotgun firing a two shot burst at the same target. Rounds such as these are often fired at the ground ahead of a crowd. When this is done randomly determine the hit location on the body adding a modifier of +2.
        The large balls are Dmg 1d+1(0.5) cr dkb Range 10/110, Rof 1x2, Rcl 1. If the required hit score is exceeded by one both balls have hit the same target.         The smaller pellets are Dmg 1d-3(0.2) cr, Acc 2, Range 20/120, RoF 1 x 48, Rcl 1, Bonus to Hit +5.

Stormtubes.
          Stormtubes are an alternate model of disposable launcher originating from Australia. Like DGLs they are preloaded and disposable and are used on accessory rails and other mountings. Stormtubes use a superimposed load system that has several projectiles loaded sequentially in a single barrel. The rounds can be fired individually or all at once, subject to the user's tolerance of recoil.
          A variety of calibres are offered but a typical Stormtube would carry three rounds, each equivalent to a 40x46mm HEDP grenade. Programmable fusing is an option for these rounds if the mother weapon has suitable FCS. An alternate model of stormtube might carry five 20mm micro-missiles or shells.

Weapons: AKVs and Effectors.

In the last couple of blogs I have considered some of the weapons available to spacecraft in TS. I have even suggested some new systems. All of these weapons have been relatively short-ranged. One of the features of space warfare will be that the enemy will often be visible at very great ranges.

An modern astronomical infra-red sensitive telescope can see a heat source equivalent to the space shuttle’s main engines out at the orbit of Pluto (about 40 AU). We can assume a future space warship will carry telescopes at least equal to the best used by modern astronomers. Such instruments will cover a large slice of the electromagnetic spectrum including visible, infra-red and ultraviolet light as well as radio, gamma and X-rays. A spaceship using its engines will be visible to anywhere in the solar system where there is a clear line of sight. How far away will a ship be visible if it is coasting? My sources differ on this but this estimate suggests 4% of an AU, or about 20 light-seconds. If the spaceship is moving at 1% of light speed it will take just over half an hour to travel this distance. At 11km/s it will take over 6 days. In other words, an enemy has plenty of time to prepare for an approaching ship. Detection range of a coasting spaceship may be even greater than the 20 light-seconds one source suggests.

 If, by some wondrous means, your ship was totally non-reflective it is still likely to appear as a darkspot at some wavelength range as it passes before stars and other objects. The same problem occurs if you could somehow cool one face of your ship to ambient temperature.

Stealth requires something to hide in or behind. In the vacuum of space there is nothing, so there is no stealth in space. While space is very big, it is also very empty and cold, making a ship or any other object visible if you look for it in the right place. Any spacecraft is going to appear warmer than its background. Even if a ship was perfectly insulated it would have the problem of finding a way to shed the heat its systems and crew will naturally produce.

An engine flare observed 40 AU away is actually an event that happened more than five hours ago. This is the time it will take visible light, infra-red or other electromagnetic radiation to travel this distance. There may be considerable difference between where a ship actually is now and where it was observed.

The vast volume of space will probably mean that active sensor systems such as radar will only be useful if you already have a pretty good idea where the enemy is. Transmitting radar pulses over a wide area will be a pretty good way to let the enemy know where you are so the active systems used will probably be highly directional tight-beam radar, lidar or maser systems. There may be no true stealth in space, but drawing attention to yourself and telling the enemy exactly where you are is still not prudent. It is likely a warship will deploy a sensor drone for any active detection duties.

Passive systems such as multispectral high-power telescopes and detectors will probably the primary means of initially locating the enemy. Computers will process images and look for objects with unnatural behaviour.

While full stealth is not possible ships will probably attempt to minimise their signature over as broad range of the spectrum as possible, making it harder for weapons to lock onto them.

Whilst detection cannot be avoided strategies such as misdirection and deception will be used to avoid identification and targeting. Their behaviour may try to mimic natural celestial bodies, so if they are seen they will be mistaken for objects such as wandering asteroids or friendly craft. In some science-fiction systems small ships use planetoids as heat sinks or hide in the space junk accumulated at the Lagranian points. Courses that pass behind celestial bodies or in front of strong EM sources like the sun may also be used where practical. An enemy will not see you if he does not bother to look in your direction.

Spacecraft may detect enemy targets hours, days or even weeks distant. The short ranged energy and projectile weapons described previously in this blog cannot be used to engage such targets. Some form of long-range missile will be needed.

One analogy for space combat describes it as resembling two nuclear submarines on opposite sides of the ocean duelling with ballistic missiles. The important caveat here is that a submarine’s primary defence is its ability to hide, which is not generally an option for spacecraft.

Below: Wasp Drones from Silent Phoenix.

The space combat missile is likely to be a very sophisticated device. The distinction between a missile and a drone becomes blurred here and essentially the terms become interchangeable. In Transhuman Space the major weapon systems for spacecraft are the Autonomous Kill Vehicles (AKV). AKVs are unmanned spacecraft armed with laser and/or coilguns that use these weapons to engage enemy vessels at close range. AKVs will also ram targets if necessary. Rogue AKVs left over from a war years before pose a hazard to shipping, attacking vessels their outdated IFF does not recognize. These rogue AKVs are sophisticated enough to maintain and supply themselves by salvaging other spacecraft.

TS AKVs vary from 30-300 tons mass, with 100 tons being typical. Where the number of AKVs carried by a larger craft is given in sourcebooks it is usually only three or four. Other entries do not specify the number carried but describe hanger bays of only 200-1,ooo tons capacity. Large TS spacecraft do not seem particularly well equipped for sustained combat. Obviously it is in a commander’s best interests to conserve and reuse his AKVs if possible. An AKV would need to retain at least half of its delta-V for a possible return trip. If it is decided to sacrifice the AKV the excess delta-V can be used to boost ramming speed.

It seems logical that the AKVs be supplemented by lesser forms of long-range missile. I will call these “effectors”.

The missiles that we are most familiar with are long aerodynamic shapes that generally fly towards their target until their fuel burns out. A typical effector drone is a barrel-shaped object that may be the size of a small car or bigger than a bus. Its shape makes it easier to store and handle within the warship. Conical and spherical variants are also known. In space combat an effector may take hours or even days to reach its target and may fly sophisticated courses, exploiting local conditions for sling-shot orbits or cover. Essentially the effector is a robot spacecraft on a one-way trip. The missile has several advantages over a manned craft. It will have a greater G tolerance so can use manoeuvres and tolerate accelerations that a manned craft cannot. Unlike the larger and more expensive AKVs it is not expected to be reused and a warship can carry a useful quantity. It also does not need to save fuel for the return trip and needs no life support resources so can be smaller and faster.

Effectors do not generally have launchers or missile tubes. Drones are stored in any available unpressurized cargo hold or hanger. When it is time to fire a drone the cargo handling system simply carries one to the nearest hatch and releases it. The effector’s secondary propulsors push it away from the hull until it is far enough away to activate its main drive. As it accelerates away it will unfold like a flower to reveal sensor masts, radiator wings and tower-mounted attitude jets. Since a target may be hours or even days away this seemingly leisurely way of launching is not a significant delay. For larger effectors might be carried clamped to the outside of the hull, as some AKVs are carried.

Once the effector has reached and located its target it must find some way to harm it. The simplest option is to simply crash into the target.

"An object impacting at 3 km/sec delivers kinetic energy equal to its mass in TNT."

When the velocity of an object reaches 3km/sec its kinetic energy becomes equal to the explosive energy of an equal mass of TNT. This is an exponential relationship in that at double this speed the object will have four times the energy, at triple nine times and so on. An object moving at 7 miles per second Earth escape velocity has about the energy of the explosion of fourteen times its mass in TNT so any impact will have a considerable effect. Kinetic energy continues to increase with increases in relative velocity. At relative speeds of over 190km/sec kinetic energy of two objects impacting begins to exceed that of a nuclear weapon of equivalent mass. The problem here is that of actually hitting the target given the speeds of the objects involved. Doubtless, however, if its other offensive systems fail an effector or AKV will attempt to crash into a target.

Nuclear warheads are an obvious choice for a missile, although combatants in TS are wary of escalating to the use of nuclear weapons. The absence of atmosphere in space means that the blast effects of a nuclear weapon will be greatly reduced and the majority of the warhead’s energy will be converted into X-rays and gamma rays. A nuclear explosion in space has been described as being a momentarily brief, very bright flash without the fireball and billowing clouds so beloved by special effects departments. The damage range of a nuclear explosion in space is likely to only be about a kilometre in radius. Within this distance the damage will be considerable but getting a warhead to within a kilometre of a target moving at interplanetary velocities may be problematic. Since an explosion is a spherical event increasing the size of the warhead only offers limited returns. A warhead ten times more powerful only increases the effect area by about two and a half times. More practical may be to fire a number of smaller warheads in a pattern and hope one will get close enough.

The lack of atmosphere will also greatly reduce the potency of conventional explosive warheads too. An explosive warhead that makes contact with a target or penetrates the hull will do considerable damage but proximity detonations will have only limited effects.

The effector or AKV may have its own laser systems and other directed energy weapons that it can use to fire on the target from relatively close range. Effectors are well suited to the application of “bomb-pumped laser” systems. These are weapons that use the detonation of a nuclear or non-nuclear device to provide power for a brief, intense burst of directed energy such as an X-ray laser. Transhuman calls these “Teller mines” after the physicist Edward Teller. The X-ray Laser Munition Pack (XLMP) fired from an AKV or larger ship’s coilgun consist of a number of these devices with a total mass of 9.5 tons.

“The exception is the X-ray laser warhead (“Teller mine”), a stand-off weapon which detonates a nuclear bomb and uses its radiation to energize multiple coherent X-ray beams. The bombs are kicked out a few miles from the firing craft by electromagnetic coilguns. coordinated by communications lasers. and directed using the main vessel’s sensors. where they deliver a short-ranged but lethal one-time punch.” [TS 3e p.10]

A bomb-pumped laser device will destroy the firing platform but this is not a concern if the system is mounted on a disposable drone or missile. Included in this class of weapon is the shaped nuclear charge, a weapon that focuses the majority of its energy into a cone-shaped discharge of X-rays and plasma that is aimed at the target. An effector might carry a number of sub-munitions armed with bomb-pumped DEWs. During the final attack phase these would spread out and fire upon the target from several directions at once. Possibly the sub-munitions would use communication lasers or some other system to coordinate their attack between themselves.

An interesting variant of the above is idea is to use Lithium Deuteride in a projectile and the energy of a high velocity impact used to compress it into an exothermic reaction. I like to think this might have been what the “Nuclear Pellet Launcher” mentioned in the TTA series of books was.

Electromagnetic pulse weapons are another attack option, although for these to be useful they must have a wider effect area than a conventional nuclear weapon. An EMP weapon could be used to blind or disrupt a target’s systems so they would be are most useful if used to soften the target up for more destructive attack systems.

One of the most cost-effective means of attacking spacecraft might be a Victorian idea, the shrapnel warhead. As stated above, at relative speeds exceeding 3km/sec a solid object has greater kinetic energy than the explosion of the equivalent weight of TNT. A shrapnel warhead may contain a small bursting charge and a mass of solid projectiles such as 2"/ 3lb cast iron balls. Cast iron balls seem the sort of thing that could easily be manufactured in a free-fall environment from an asteroid or scrap. One can easily envision a large spacecraft manufacturing its own.

An exploding shrapnel warhead would create a cloud of shot over a large area, which may exceed the effect area of a nuclear weapon in volume. The effect area would also be more persistent. Warheads could be detonated so that the sub-projectiles either hit the target or the target flies into them. The small size and number of balls would make it difficult for a laser defence system to destroy them all. A laser system would have to vaporize each ball since they would still be a threat if molten or broken up. An interesting idea would be to pack the balls in sand or carbon dust to form a cloud that would interfere with laser fire. The shrapnel warhead itself would be rather robust. A nuclear explosion is a complicated event to initiate and relatively minor damage to the nuclear device might render it inert. The shrapnel warhead is mainly inert metal so would be more tolerant to damage from defensive fire. If the warhead is broken up or detonated the scattered shot would still pose a hazard to the defender.

The tungsten pellet Kinetic-Kill Munitions Packs (KKMP) used by AKVs and larger ships in TS are similar in principle to the shrapnel warhead but on a larger scale. The ten-shot KKMP needs to be launched from a coilgun, has a total mass of 9.5 tons, and occupies 250 cubic feet. Each shot therefore launches nearly a ton of tungsten pellets. [TS 3e p.188 and 197]

The shrapnel warhead and KKMP are not the only forms of kinetic weapon possible, of course. The effector may pack a number of larger short-range kinetic kill missiles, effectively the offensive equivalent of Kirklin mines. These might be designed so that if hit by a defensive laser they break into large fragments and/or release smaller “child” KE missiles so continue to be a hazard to the defender. 

Probably an attacking effector or AKV will use a mixture of offensive systems, releasing a number of sub-munition warheads of various types while attacking with directed energy and jamming systems. Larger models of drone or AKVs may also utilize railguns as armament, allowing them to attack if they pass within a few kilometres of their target

Typically an AKV can only carry a single, ten-shot munition pack and launch it from a coilgun mounted to be forward firing. A railgun is a much lighter system and can be turret-mounted. The railgun gives the AKV the capability to engage multiple targets. Railguns are capable of accelerating a projectile at phenomenal speeds. A railgun round that penetrates a ship’s hull is likely to perforate a number of internal compartments as well, possibly punching out the other side of the vessel. Smaller targets hit by a railgun will be shattered, pulverized or even vaporized. A hit from a railgun can be devastating but in a vacuum a miss of a few inches will have negligible effect on the target.

A railgun round may be accelerated at 20,000 to 60,000g and such forces pose considerable problems in creating guidance systems suitable for a railgun rounds. Whether these challenges will be solved by the TS-era, or will actually need to be addressed remains to be seen.  It can be assumed the majority of railguns use unguided rounds. Acceleration forces also make it problematic to use unstable compounds such as explosives in railgun rounds. When a projectile’s velocity exceeds 3km/s the need for an explosive component is debatable. Railguns generally use solid shot or “slugs”, either of hardened steel or steel with a tungsten or depleted uranium core. A 3" calibre railgun slug or shot for a 5" (127mm) railgun masses about 33 lb. Each round is acutely pointed but this point is covered by a cap of softer material (above) that reduces the chance of a round glancing off armour. AKV railguns use the same ammunition as other railguns but tend to be simpler than other models since they are likely to only be used for a short duration. Waste heat production and excessive wear are less of consideration on such models. A railgun can be refurbished if the AKV survives its mission. Instead of the 5" railgun some AKVs and smaller vessels mount a 3" railgun that fires a 57mm projectile of 15 lb mass. The 3" railgun permits more rounds to be carried within a given volume.

Below is a tentative proposal for such railguns, based on the rules in Spaceships (4e). Railguns are typically turret mounted. 

Weapon	d-Damage	sAcc	Range	RoF	Shots	Rcl	WPS	Notes
3" Railgun	6d x 2(2) x V	-7	S	[p.58]	50	3	15lb 1/133t	[1, 2]
5" Railgun	3d x 7(2) x V	-7	S	[p.58]	150	3	33lb 1/60t	[1, 2]

[1] d-Damage is multiplied by relative velocity (V) of combatants and subject to an armour modifier of (2). Minimum relative velocity for these railguns is 3 mps.

 [2] Rof value varies with turn length and weapon type. See p.58 of Spaceships (4e) for Rof.

The enemy may be well aware that an effector or AKV is on its way and have several days to prepare. He may launch an effector or AKV of his own to destroy the incoming threat. This suggests that the attacking vessel may have their own defensive systems and the defensive vessel counters to these. The effectors and AKVs will doubtless use ablative armour, evasion and other defensive methods to increase its chances of reaching the target.

An effector will have to be a fairly sophisticated robot spacecraft in its own right and it is highly likely that some may be retasked spacecraft. In this article on “Killer Buses” commercial, obsolete or surplus spacecraft are used as missiles, echoing the use of fireships and hellburners during the age of sail and the use of explosive-packed ships in later conflicts. As has been explained already, such a ship does not even need to be filled with explosives to make it a weapon. Its mass and velocity will make it lethal enough and even if it is destroyed the fragments produced may remain a hazard to the target. It is feasible that such a ship will contain sub-munitions and interception counter-measures. The distinction between ship and missile becomes increasingly blurred as we consider space warfare. One can envision a captain desperately launching his lifeboats and shuttles to destroy an incoming threat           

Particle Accelerators and Coilguns.

Many of the space warships in Transhuman Space (TS) include neutral particle accelerators as part of their armament.

 In TS 3e ship-building rules particle accelerators were brought in 50 foot increments, the longest known example being 400 ft long. One of the reasons for the popularity of cylindrical hulls was that a linear particle accelerator could be installed running down most of the longitudinal length of the hull. This arrangement only allows the particle weapon to fire into the ship’s forward arc. Spaceships 8 design rules represent this by treating particle weapons as fixed mounts on the forward hull. While the weapon extends most of the length of the vessel it is generally not massive enough to count as a spinal mount. If you had a ship that expected to get chased a lot it might be prudent to build a vessel with a rearward firing particle weapon! The Archangel-class SDV [Spaceships 8 p.29] design has a pair of particle beams but both are mounted for forward fire. Legally only warships are permitted to mount particle accelerators. In Spaceship 8 rules particle beams can only be mounted on ships of SM+8 or larger and must be major, medium, or spinal batteries, installed as fixed mounts (a +2 to hit) with either the rapid fire or very rapid fire options. The Salahudin Samboja [Spaceships 8, p.31] appears to be an exception, mounting a 3GJ weapon, the maximum size of non-rapid major battery weapon for the SM+10 hull.

The Atomic Rockets webpage has some interesting discussion of the real word strengths and limitations of particle beams as weapons. Particle beams cannot be focused as tightly as a laser, giving them less range than a laser of equivalent power. On the plus side the particle beam has greater penetration. A laser beam stops on the surface of a target and attempts to burn through. A particle beam will penetrate deeper, causing local heating and also producing levels of radiation dangerous to both electronic and biological systems. In Transhuman Space laser weapons are limited to 300MJ or less. Particle beams are available in the GJ range.

The requirement for a forward mounting raises some interesting questions. The spacecraft can only fire its particle beam at a target the hull is pointing towards. Of course, in space combat a ship can point in a different direction to the one that it is travelling in. Most of the ships in TS appear to be “tailburners”. They have one large engine at the end of the vessel. Presumably they decelerate by pointing the drive forward and change course by orientating the drive in the appropriate direction. Suppose such a ship is heading “north” and wants to head “east”. The ship would reorientate so that its drive is pointing “northwest”. Thrust from the drive would cancel the northward motion and move the ship eastward. It should be obvious that during this process the forward-firing systems of the ship can only engage targets to the “south-east”. The ship cannot fire and manoeuvre at the same time! This is why I have proposed designs of military spaceship with multiple major thrust ports, permitting changes of direction or speed without reorientation.

Another consideration for the fixed mount is one of accuracy. When a target is thousands of miles distant the margin of error will be in terms of fractions of a degree. It seems unlikely that a ship hull of 10,000 to 30,000 tons can be orientated with sufficient finesse. The particle weapon itself will weigh 20-40 tons for every 50ft of length, [TS (3e) p.182] so sufficiently fine movement of this mass is unlikely to be practical either. The spaceship will need some mechanism to influence the path of the beam magnetically. The particle beam is neutralized just before it leaves the “muzzle”. Beam trajectory will need to be set while the beam is still in its charged state.

Coilguns are another weapon found on some large TS spacecraft. In TS 3e all coilguns were 333mm [p.181] and fired “munition packs”. A Kinetic Kill Munition Pack (KKMP) held several canisters of tungsten pellets. A X-ray Laser Munitions Pack (XLMP) had canisters holding several nuclear bomb-pumped X-ray laser weapons [TS 3e p.102, p.188]. Both types of munition pack massed 9.5 tons, occupied 250 cubic feet and held 10 shots [p197]. (This implies each coilgun round is more than 26ft/8m long! Perhaps each shot is a fusillade of smaller canisters.)

In Spaceships 8 coilguns are considered to be equivalent to electromagnetic guns and their power varies. AKVs carry coilguns equivalent to 10cm or 12cm guns. Larger vessels carry guns of 14 to 24cm equivalence, representing that larger vessels can mount more powerful coilguns that can fire the same munition packs at greater velocities. Potentially a coilgun as long as the ship could be created. These may in fact be the systems represented by fixed forward mounts of medium size or greater. Despite this, coilguns are relatively low velocity weapons in the context of space warfare and are thus limited to shorter range engagements. Minimum relative velocity modifier is 2 mps. See Spaceships 4e [p.58, p.68] for effects of 10-24cm electromagnetic guns and space combat. (Note that the p.68 table is subject to a correction in Spaceships Errata. dDamage for 10cm-24cm is actually 3dx5 - 6dx6)  Spaceships 8 [p.9] has rules for X-ray laser munitions. KKMPs are treated as conventional 10-24cm rounds for damaging purposes with no armour modifier. Each coilgun bay contains one munition pack giving 10 shots. It is up to the GM as to whether a coilgun bay can be reloaded during a combat. Given that each munitions pack weights nearly 10 tons this will only be practical on larger spaceships if allowed.