Rockets and Missiles
What’s with the designations?
The USCM apparently use a couple of different methods for naming weapons. Some of them seem to use something based on the 1963 United States Tri-Service rocket and guided missile designation system, which starts with three letters; the first indicating the platform the weapon is launched from (some of these letter codes seem to be different to the modern-day version), the mission or target for the weapon, and whether it is a missile (i.e. has some form of guidance), (unguided) rocket, or probe. Different systems within the same code use sequential numbers, and different versions of the same system have a letter on the end which goes in alphabetical order. For example, the AGM-204C is the third (C) version of the 204th air-launched (A) ground/surface-attack (G) missile (M). Others (mostly unguided rocket launchers rather than missiles) use something like the MIL-STD-1464A Army Nomenclature System, which usually consists of the letter M (for model or mark), a number (sequentially assigned for each type of equipment), and optionally the letter A (for ‘Approved modification’) and (sequential) number to indicate modified versions. For example the M83A2 is probably the 2nd approved modification of the 83rd model of anti-tank missile. In the ANS, experimental models are designated XM rather than M, and experimental modifications are designated with an E rather than an A. However, many items don’t fit this pattern, indicating that it isn’t an entirely identical system (probably a result of writers not doing their research and just using whatever letters they liked). Even in the real world, you sometimes see designations which don’t seem to fit any obvious pattern.
M5 Rocket-Propelled Grenade
‘Rocket-Propelled Grenade’ is a name which has never actually been officially used for a real-world weapon so far as I’m aware. The Russian term Ruchnoy Protivotankovy Granatomyot means ‘hand-held anti-tank grenade-launcher’. Americans have traditionally favoured the terms ‘recoilless rifle’ or ‘rocket launcher’ for their kit, only using ‘rocket-propelled grenade’ as an unofficial term for the Russian-designed weapons.
Anyway, this is a fairly straightforward reusable bazooka-style launch-tube firing a 60 mm, 2.2 kg unguided, spin-stabilised rocket. Apparently it is a hypervelocity weapon. How fast you need to be in order to qualify as ‘hypervelocity’ seems to vary; the US Army classify a tank gun with a muzzle velocity of 1,021 m/s as a ‘hypervelocity gun’, but small arms are only hypervelocity above 1,524 m/s, and hypersonic missiles are those that go above 1,700 m/s. None of those are impossible if you assume some reasonable futuristic propellants and miniaturisation, but it certainly looks like an engineering challenge, especially at the higher end.
The warhead is an impact-fused supercritical HEAT (High-Explosive Anti-Tank; a shaped-charge which uses the Munroe effect to drive a liquified jet of metal through armour). ‘Supercritical’ seems to be simply technobabble here, and impact-fusing doesn’t seem like a great choice for something that might be moving at 1,700 m/s (although it may be a result of having to be proof against radar-absorbing surfaces, jammers, etc.). Presumably the high speed is to overcome active defence systems, since a shaped charge shouldn’t really be affected much by speed of impact. Even at 1,700 m/s a HEAT warhead would be justified over a solid penetrator with modern-day technology (back-of-a-napkin math says about 140 mm penetration in mild steel vs. more than twice that for the real-world NAMMO 66 mm M72A2 Light Anti-Tank Weapon, although the difference would be less dramatic with more advanced armour), and the Aliens setting seems to have significantly more powerful explosives (given the spectacular effect of 30mm grenades). Even so, it is described as ineffective against medium or heavy tank armour (presumably from the front).
Accurate range is about 400 m with a telescopic sight and maximum range is 2,000 m, both of which seem unremarkable. Although not mentioned in the Technical Manual, the combination of speed and accuracy should make it capable of hitting slower aircraft. Each USCM platoon generally has either two M5 RPGs or two M76 PIG plasma guns, for dealing with light armoured vehicles and bunkers.
A different weapon (capable of holding four rockets in a magazine) with the same name appeared in the video-game Aliens: Colonial Marines. It’s possible that the naming system has different sequences for single-shot rocket launchers and magazine-fed ones, making it possible for two similar items to both have the same designation code (for example, the US Army fielded both carbines and rifles, multiple different anti-aircraft guns, about a dozen different tractors, as well as a bayonet, a flamethrower, a grenade, a mortar, and a rocket launcher under the designation ‘M1’ in WWII).
M6B Rocket Launcher
This weapon only appears in the video-game Alien vs. Predator 2. It is an auto-loading launcher which holds three rounds. It shoots both ‘direct fire’ and ‘tracking’ rockets. It isn’t clear what the tracking rockets use to identify targets, but it seems to work against aliens and cloaked predators, and the manual claims it works best against moving targets, so possibly motion-tracker (ultrasound SONAR) or millimetre-wave radar. It might be the successor to the M5 from Aliens: Colonial Marines, given the similarities.
M83A2 SADAR
The Shoulder-launched Active-homing Disposable Anti-tank Rocket is a heat-seeking ‘fire-and-forget’ anti-armour missile in a disposable launch tube. Few hard figures are given for it, beyond its weight (3.2 kg) and range (20-1,000 m). It uses a smart guidance system which can make top attacks against vehicles and outsmart some countermeasures like flares (this can be disabled in order to simply use it as a rocket launcher). It uses a HEAT warhead like the RPG, but in this case it is described as being effective against medium armour, presumably thanks to attacking the weaker top side of vehicles (it doesn’t seem to be much bigger). To make it a little safer for use in crowded or enclosed spaces, it uses a countermass of plastic pellets to reduce back-blast. All of this is entirely believable given the setting assumptions; many modern anti-tank missiles have similar capabilities, the only real advancement is packing it all into a smaller package.
A rifle platoon is assigned 18 SADAR, enough for each dismounted member (i.e. all squad members and the two section sergeants, but not the APC drivers, lieutenant, or platoon sergeant) to carry one if they want.
The video-game Aliens vs. Predator: Extinction features the M83AM SADAR AMAG (‘aerosol magnesium’), a four-barrel version of the SADAR with added thermobaric effect. This seems to have been based on the real-world M202 FLASH, a 1970s incendiary rocket launcher.
M112 HIMAT
The Hypervelocity Intelligent Missile, Anti-Tank is a larger (11.3 kg) weapon, which needs to be emplaced before use. It consists of a disposable launch-tube with base-plate and bipod, which is set-up rather like a mortar. Inside the tube is a single missile.
The launcher is connected to some form of fire-control device, without which it cannot fire. This can be a computer (APS-100 Fire Controller) which draws data from connected local sensors in order to identify targets and launch automatically at them, a remote terminal where a human operator does a similar job, or a target-acquisition sight (SR-90 with IR and motion tracker capability, or SR-105 with IR and millimetre RADAR) which can be used to pick out targets directly.
The missile uses a two-stage rocket motor, the first stage propelling it out of the tube and aligning it with the target, the second accelerating it to hypervelocity (here defined as about Mach 4.5, or 1,490 m/s at sea level on Earth). It uses thermal imaging (IR imager in the 8-12 micrometre range), millimetre-wave radar, and a radio receiver (which allows it to home in on jammers and RADAR) in order to locate and identify the target. It’s smart enough to self-destruct if launched at a friendly vehicle, and otherwise tries to pick the most vulnerable point to hit.
The warhead is a solid tungsten penetrator, surrounded by an explosive charge which gives it some extra ‘kick’, and is said to be effective against all but the strongest tank armour (presumably after accounting for their targeting of weak points; a story describes them bouncing off tank glacis armour when they failed to correctly identify the layout of unfamiliar tanks). Although theoretically effective at over 5 km, active-defence systems reduce practical range against state-of-the-art opponents to around 1 km (which implies that point-defence systems in the Aliens setting can eliminate a threat in under 0.7 s). High-speed and a capable sensor package means that it is somewhat effective against slow aircraft and the CMTM says that a multi-purpose warhead for use against air and ground targets is being developed.
HIMAT is a company-level asset, which may be attached to line platoons. They seem to come with dedicated tank-hunter teams to operate them.
The HIMAT is conceptually similar to the never-fielded Vought / Lockheed-Martin line of kinetic-energy missiles (HVM, LOSAT, and CKEM) and presumably exists for similar reasons (wanting to engage fast-moving targets with good active defences at long range).
DSGR Smart Missiles
These aren’t in the Technical Manual, but are listed as one of the APC’s weapons in the initial design notes and appear in Alien: The Blueprints. The two angled panels on either side of the APC’s roof are apparently launch bays, each holding six multi-role (presumably air-intercept and surface-attack) missiles. Each missile is 51 mm in diameter, and is laser-guided. Guidance options are lock-on-before launch, after-launch, or handing-off to a separate laser designator. They seem to consist of an older propulsion system with a new guidance package (and possibly warhead). The description mentions precision strikes on targets close to friendly forces and civilians, so I think they are probably kinetic weapons with no explosive component. This makes sense since all weapons on the M577 APC (except for the laser turret on the M577A2 variant) have significant risk of collateral damage (blast effects from the plasma cannon, radiation scatter from the particle beams, or simply large numbers of not-very-accurate shells from the rotary cannon).
SIM-118 Hornet
A shoulder-launched surface-to-air missile (the kind of weapon known in the real-world as a MANPADS, or MAN-Portable Air-Defence System). It uses a millimetre-wave ‘seeker’ (presumably meaning RADAR), has a range of around 10 km, and no real warhead, relying on simply smashing into the target at hypervelocity. No other details are offered, so it isn’t clear how big they are, or whether they are one-use, or what.
Like HIMAT, they are company-level assets which are attached to platoons. It is possible that they are crewed by specialist teams or simply handed out to regular infantry.
There are some naming similarities to the real-world FIM-92 Stinger. I guess SIM means something like ‘Shoulder-launched (or Single-operator) air-Interceptor Missile’ (S__ isn’t a real-world American missile launcher code; F__ is for infantry launchers).
LIM-417 Phalanx
The ‘primary SAM’ (Surface-to-Air Missile) of the USCM is a long-range hypervelocity missile capable of hitting targets ‘to the limits of the stratosphere’ (obviously variable depending on the planet, but if it means the upper limits, that’s about 50 km up on Earth). To achieve that, it uses a three-stage booster (it isn’t totally clear if that means detaching booster engines as it goes, but I think that is what was intended). It has RADAR, as well as a broad spectrum of passive sensors (UV, visible, IR, and radio-frequency jammer homing), and can take guidance from a ground station to ensure a hit. The warhead is a bunch of darts, which can have their dispersal pattern optimised by an adjustable fusing mechanism.
It isn’t clear at all how big this thing is or what kind of platform it launches from. It’s another one of those company assets which gets attached to platoons, which implies it is capable of fitting inside an APC, but the designation LIM rather than SIM (as well as its range) suggests it isn’t shoulder-launched. In modern-day US missile terminology an L__ missile would be launched from a silo. For example, the LIM-49 Spartan was a 13 tonne anti-missile missile armed with a nuclear warhead. It’s unlikely that a rifle platoon would have a silo-based weapon assigned to them, so this must be another difference in nomenclature between the 20th century and the 22nd.
HIM-122 Lancer
An area-defence missile (presumably ground-launched) able to reach from medium altitude to the mesopause (85 km up on Earth) with ten independently manoeuvring warheads (what type isn’t specified). Apparently controlled entirely from a ground station via an ‘unjammable’ datalink (I guess laser in a cloud-penetrating frequency, i.e. blue, around 475 nm). The primary mission seems to be defence against ballistic missiles and orbital bombardment, but it can also engage aircraft and even low-flying spacecraft.
This is a battalion-level support asset, so presumably a fairly substantial bit of kit, but details are distinctly lacking. H__ missiles in the 1963 TS R&GM DS would be stored in hardened silos and raised to ground level before launch, but I don’t think any such weapons were ever actually built. If S__ missiles are man-portable, and L__ ones are launched from emplaced launchers, then H__ ones might be ground vehicle-mounted.
XIM-28A Long-Lance
A space combat missile. Eight of these make up a Conestoga-class starship’s main armament, so they are a pretty big deal. Each is 5.6 m long (about the length of a Ford Transit van) and has a two-stage motor, one for launch and the other for terminal guidance. It uses a mix of emission homing, IR imaging, and RADAR (in the 8-12 GHz range, AKA microwave or x-band) to find targets. The warhead is a forged-fragment ring, which I think means an annular-blast fragmentation or continuous-rod design (essentially a ring of metal which is folded up and then ‘unfolded’ by explosives into a circular pattern).
In the real-world ‘X’ is usually used for experimental systems and ‘I’ for air-interception, while the code for space targets is ‘S’, so this ‘should’ be something like VSM-28A rather than XIM-28A.
HIM-78 Sprint
This is a surface-to-orbit ASAT (anti-satellite) missile, with a two-stage booster (I think this means there is one booster engine and then the main engine). It can reach as far as geostationary orbit and uses a ‘kinetic’ warhead (I guess that means just crashing into the target). Like the Lancer, it is a battalion-level asset. I expect that it is larger than the Long-Lance (since it needs much more powerful motors to lift out the gravity well), meaning that it probably needs its own dedicated launch vehicle.
M201 Multiple Launch Rocket System
The heaviest artillery in USCM service is a tracked missile transport carrying eight 250 mm rockets. These can deliver submunitions and mines up to 120 km away (this is far enough to count as a short-range ballistic missile). The description seems fairly similar to the real-world M270 Multiple Launch Rocket System.
Mk. 16 Banshee 70
A 150 mm, 70.8 kg unguided rocket launched from the LAU-190/A launch tubes on the UD-4 Cheyenne dropship. Has a burn-out velocity of over 1,500 m/s and comes with a huge variety of warheads, including incendiary, explosive, multiple-dart, cluster bomblet, smoke, and chemical.
Mk. 10 ZEUS
A smaller (70 mm, 15.8 kg) unguided rocket, also carried by the Cheyenne. Only has two warheads: one smart-fused (i.e. airburst) fragmenting, one smoke.
Mk. 88 SGW
A small (12.2 kg) fire-and-forget (IR homing) short-range (1,500 m) air-to-surface missile with a 120 mm 2.2 kg shaped-charge warhead.
AGM-220C Hellhound II
The most capable air-to-surface weapon carried by the Cheyenne uses a three-stage motor and has a combination of millimetre-wave RADAR and IR imaging for target identification. It is smart enough to operate as a ‘brilliant’ weapon, hunting and attacking targets without human guidance up to 70 km away. The missile weighs 264 kg, of which 107 kg is the blast-fragmentation warhead. The Hellhound II has a similar name, appearance, and role to the real-world AGM-114K Hellfire II.
AGM-204A TSAM
The Threat Suppression Attack Missile is a ‘defensive’ weapon which can be set to launch automatically when a dropship is targeted by missiles or anti-aircraft artillery. It accelerates to hypervelocity in 2 seconds and has a range of up to 60 km at high altitude. Its passive sensors are able to detect a wide range of wavelengths (allowing it to home in on targeting RADAR, LIDAR, etc.) and it has an active millimetre-wave RADAR for terminal guidance too. It is a bit heavier (303 kg) than the Hellhound II, but carries a smaller (61 kg) blast-fragmentation warhead.
The TSAM is conceptually similar to real-world anti-radiation missiles such as the AGM-88 HARM. Notably, it is a good match in size and capabilities to the AGM-88E AARGM, which wasn’t fielded until two decades after the Colonial Marines Technical Manual was written.
AGM-660 Warhawk
A ground-attack missile carried by the EVAC-3 fighter. In the Kenner toy line where the EVAC-3 originally appeared, it was armed with Alienator missiles. Presumably that name was considered too silly by the RPG writers.
Hellcat Missile
A ‘light missile’ found on the XT-37 Stinger light attack vehicle. The XT-37 is another vehicle which originates from the Kenner toy line and was also armed with Alienator missiles, which were noted as having a 300 m range (rather short for a guided / homing missile). The similarity in name may imply that the Hellcat is a variant of the Hellhound for use on ground vehicles.
AIM-90E Headlock
A short-range (18-24 km) air-to-air missile. It weighs 96 kg, travels at hypervelocity, and uses a combination of optical and RADAR sensors to home in on its target. The warhead consists of 34 explosive darts, which are spread in an ‘optimum attack pattern’ depending on the target profile.
Small Arms and Machine Guns
M41 Pulse Rifle
The pulse rifle is the most iconic weapon of the setting, appearing in Aliens, Alien 3, and numerous spin-off comics and games. It fires 10 mm caseless ammunition (specified as ‘10mm✕24’ in the Aliens Colonial Marines Technical Manual; in a conventional cartridge, the 24 would be case length, but I don’t know how that would work with caseless rounds) which is detonated with an electric pulse (hence the name ‘pulse rifle’) rather than a conventional primer / firing-pin arrangement. Such a mechanism can potentially give a more controlled deflagration of the propellant charge, possibly sustaining high pressure in the barrel for longer and thus producing a high muzzle velocity with less recoil and stress on the chamber. The entire mechanism is ‘floated’ to reduce felt recoil further, and seems to be pretty controllable (Hudson was able to shoot bursts one-handed at a facehugger).
The Technical Manual gives quite a lot of detail about the ammunition, telling us that the propellant is a rectangular block of Nitramine 50. Nitramines are a real class of chemical, which includes explosives and propellants such as Octogen (1,3,5,7-Tetranitro-1,3,5,7-tetrazocane, AKA High-Melting Explosive, or HMX) and HNIW (hexanitrohexaazaisowurtzitane, AKA CL-20), so I guess that’s fairly plausible. Rectangular propellant charges were used in the H&K G20 and are very space-efficient, but must cause some issues with edge crumbling and alignment which could easily be avoided with cylindrical ones. The standard M309 light armour piercing explosive bullet apparently masses 13.6 g and has a muzzle velocity of around 840 m/s from the M41A’s 247 mm barrel. That equates to about 4.8 kJ of kinetic energy, considerably more than a modern battle rifle (and way more than an assault rifle, but less than some sniper / anti-materiel rifles). With a hardened steel cap, penetration should be over half an inch of mild steel (and probably a similar thickness of 22nd century personal armour, which seems lighter but not much stronger than steel). The explosive charge isn’t specified, but must be fairly small. Evidently either the propellant or explosive is prone to detonating when hit by a flamethrower, as happens to the bag of ammunition carried by PFC Frost in Aliens. Maximum effective range is about 500 metres, but this seems to be due to accuracy rather than power. No other ammunition types are mentioned, although it seems likely they exist (at least some kind of solid ‘ball’ version).
All variants of the M41 have a distinctive angular carrying handle, which holds the weapon’s battery pack (good for thousands of rounds and presumably also used to power accessories) and the iron sights (protected in a groove). It also functions as an attachment rail for optics such as the AN/RVS-52 (a charge-coupled low-light digital camera sight with ✕3 magnification) or the S6 holographic sight.
The most commonly seen variant of pulse rifle is the M41A (sometimes written M41A1, which would be more consistent with modern US military naming conventions) assault rifle, which has a permanently attached underslung U1 30 mm grenade launcher. It is usually issued with 95-round magazines (a dimmable LED counter on the right of the weapon keeps track of how many rounds remain in the magazine). Apparently you can squeeze 99 rounds into them, but doing so causes stoppages. Cyclic rate of fire is 900 rounds per minute (4.3 seconds to empty a standard magazine), and there are settings for 4-round bursts and single-shots per trigger pull. Light-weight materials such as carbon fibre and titanium aluminide (bit of a weird choice, usually used in high-temperature applications) keep weight to just 4.9 kg (fully loaded, with sling) which is pretty hefty but still less than some historical SMGs (e.g. the M1A1 Thompson ‘Tommy Gun’ which the pulse rifle props were based on) and assault rifles (e.g. the original AK-47), and better than all but the lightest modern assault rifle and grenade launcher combinations.
It isn’t exactly clear which other variants of M41 are available. The Colonial Marines Technical Manual (apparently written in the early 2180s in-universe) says that only the M41A and M41AE2 are in service, but the video game Aliens: Colonial Marines has M41A Mk. 2 rifles in 2179 (this could be justified as the Mk. 2 being withdrawn around 2080 due to poor reception if you really care). The Mk. 2 is essentially a slightly lighter, more modular variant of the M41A with smaller magazines. In terms of rules in the Alien RPG, there would be little difference. Later versions such as the M41A/2, M41A3, etc. would also be basically the same.
The M41AE2 ‘heavy pulse rifle’ is significantly different though. It replaces the under-barrel secondary weapon mount with a bipod, has a 327 mm quick-swap barrel (possibly giving something like 5-15% more muzzle velocity, range, and penetration), and takes an ‘L-feed’ magazine holding up to 300 rounds (it also seems to take standard M41A magazines). It is used as a ‘light support weapon’ (a vague category of guns which sit somewhere in the assault-rifle to light machine-gun continuum, more-or-less the same as ‘automatic rifle’ or ‘squad automatic weapon’) to supplement the firepower of rifle teams (bringing them more in-line with the smart-gun teams). The M41 was developed in the early 2170s, and is described as ‘similar in concept to the Harrington Automatic Rifle of the early ‘60s’ (this was apparently a 6.8 mm rifle, notable for reliability but lacking ‘stopping power’ against armoured infantry).
Another predecessor was the original 21st Century Wayland Storm Rifle, which looked a lot like an M41 with a long barrel and under-slung shotgun (according to promotional material for Prometheus). This gun was apparently very powerful and accurate, but unreliable due to high strain placed on its (many) moving parts and complex computer targeting (somewhat justifying the shotgun attachment as a back-up). It seems to have been issued alongside the Harrington as a light support weapon. The Weyland Storm Rifle might be the pulse-rifle-like weapon frequently shown in the ‘Aliens: Defiance’ comic (set in 2137) and its sequels, but I think it’s more likely a case of the artists (like the writers) just not bothering to check the timeline. The F44AA rifle in Alien: Romulus (set in 2047) is another pulse-rifle lookalike, although it seems to fire a smaller, less powerful round, and has smartgun-like assisted aiming.
M56A2 Machine Gun (Smartgun)
The main firepower of a (dismounted) rifle section comes from its two smartguns. The M56 machine gun (‘general-purpose automatic squad support weapon’) uses essentially the same principles of operation as the pulse rifle, but with a more powerful round (M250 10mm✕28 caseless, 14.9 g variable fused explosive projectile) and longer barrel (545 mm, giving probable muzzle velocities in the 950-980 m/s range, good for at least 15% more penetration than the M41A). Better cooling and belt-fed ammunition allow more sustained fire (at a cyclic rate of 1,200 rounds per minute), but the key difference is the accuracy afforded by the stabilised weapon mount and computer-assisted sights. Although the weight and awkwardness of the targeting system are a hindrance, it allows the smartgun to effectively engage targets at up to 1.5 km (better than many sniper rifles), while being more mobile than a traditional medium or heavy machine-gun.
Weirdly, there doesn’t seem to be any ‘official’ figure for how many rounds of ammunition a smartgun drum holds. Video games give numbers of 150, 200, and 600. It’s possible that several different drum sizes are used.
The original M56 smartgun was first fielded in 2149, and was notably unreliable, causing some marine units to hold onto their more dependable M38 machine guns until the issues were resolved.
M30 Machine Gun
The M30 gun on the UA 571-C robot sentry unit is similar to the M56 smartgun, just mounted on a different platform. It uses the same ammunition, has a slightly lower rate of fire (1100 rounds per minute), and seems to have similar barrel length (both props were built around M42 machine guns). The ammunition drum (notably larger than the one on the M56) holds 500 rounds.
M42A Scope Rifle
Introduced in the Colonial Marines Technical Manual, this is a bullpup (magazine behind the firing grip) marksman’s rifle usually deployed in an USCM battalion’s scout-sniper pool. The internals share a lot of parts with the M41 series, but it takes the same 10mm✕28 caseless ammunition as the smartgun. The usual round is a ‘match-standard’ M252 High-Explosive Armour-Piercing one with better accuracy than the M250 used in smartguns (effective up to about 3 km), and there is an even more accurate stabilised ball (i.e. not explosive) round (which can reach 3.8 km). The barrel length is 81 cm, which should give a muzzle velocity of over 1 km/s (over 8 kJ of kinetic energy, more than most ‘magnum’ sniper rounds, but only about half that of anti-materiel rifle / heavy machine-gun ones like the .50 BMG). There is a flash hider, but no sound suppressor, as the sonic boom of a Mach 3 projectile would make it pointless.
The rifle is named for its large multi-spectrum (visible light, infra-red, and ‘electromagnetic emissions’, presumably meaning passive millimetre-wave) ✕20 telescopic sight (presumably a variable-magnification digital camera system). This can also connect to various other sensors and integrate their data into the eyepiece display.
The design of the M42A was obviously inspired by the real world Walther WA2000. Oddly, many Aliens video games feature sniper rifles with similar designations but completely different appearance (M42C scoped rifle in Aliens vs. Predator, M42A2 scout rifle in Aliens: Fireteam Elite, and M42A3 sniper rifle in both Fireteam Elite and Aliens: Dark Descent). Meanwhile Aliens: Colonial Marines has the M4RA battle rifle, which is a close visual match to the M42A except for having an under-barrel attachment point for a shotgun or grenade launcher instead of a bipod. It can use a sound suppressor (as can the M41A Mk. 2 pulse rifle in that game; unlikely unless sub-sonic ammunition is issued) or barrel extension (it literally screws on the end of the existing barrel; although such things do exist for shotguns, making them work with very high-powered rifles is likely to be an engineering challenge, to say the least). It also has the option to mount various optics; the S4 ✕2 telescopic sight, S11 variable-zoom (✕2-4) sight, and an infra-red smart targeting scope.
M37 Shotgun
In Aliens, Hicks carries a heavily modified (sawn off barrel and stock, with the grip from an MP40 SMG attached) Ithaca Model 37 hunting shotgun, memorably using it in the ‘eat this’ scene. Although the weapon seems to be a personal one (in the novelisation it is an old family heirloom) it made such an impression that most of the Aliens video games include a shotgun, and often call it some variation of ‘M37’. Notably the M37A2 (from Aliens: Infestation and Aliens: Colonial Marines) is a close match to the shortened ‘stakeout’ version of the Ithaca, and the M37A3 (from Aliens: Fireteam Elite) is simply an Ithaca riot gun with some picatinny rail added. The RPG has an M37A2, but in this case it seems to be a dual-tube bullpup design based on the Henjin-Garcia 37-12 shotgun from Alien: Isolation (in turn apparently based on the obscure prototype Winter SWATriplex-18). Wherever the cartridge is specified, it is invariably 12-gauge, probably the same 12-gauge standard used today.
The Ithaca 37 appears in numerous other films and TV shows. Notably, the exact same one used by Michael Biehn in Aliens was in The Professionals a few years earlier. Biehn uses a different Model 37 in The Terminator (also directed by James Cameron), as does fellow Aliens star Bill Paxton in Near Dark (alongside Lance Henricksen and Jeanette Goldstein again). Kurt Russel wields one in The Thing, and a sawed-off version similar to Hicks’ is included in the Winchester brothers’ armoury in Supernatural.
Several types of shotgun shell are available to the USCM:
Buckshot - the standard load of small metal pellets. The USCM probably use non-toxic high-density materials rather than lead.
Baton Rounds - a less-lethal option, firing a ‘rubber bullet’.
S11 Expanding Shell - mushroom-shaped ‘hollow point’ slug.
R1 Flechette Round - fires a bunch of tiny darts.
B15 Timed Explosive - turns the shotgun into a tiny grenade launcher with dubious effectiveness.
Pistols
The various pistols seen in the Aliens universe tend to be simply real-world ones with minimal modification. Most of the USMC ones are ‘9mm’ (possibly the good old 9✕19mm ‘parabellum’ round first made in 1901 and still popular today, or a new caseless one) semi-automatic weapons.
The Technical Manual says that the standard sidearm is the M4A3, which is visually very close to a Colt M1911 (and its numerous derivatives). However, no such weapon is seen in Aliens. The closest match is Vasquez’s Smith & Wesson Model 39. That has custom ‘pearl’ grips, implying that (like Hick’s shotgun) it is a personal weapon rather than a military issue one. According to the Technical Manual, the M4 series has been in service for ‘the past sixty years’ (i.e. since around 2120).
The pistol used by most characters in Aliens (Apone, Crowe, Dietrich, Ferro, Frost, Gorman, and Spunkmeyer) is the Heckler & Koch Volkspistole 70. This is a fairly obscure handgun which was chosen because its unusual profile and plastic casing made it look futuristic. It was never named in the film (the technical manual just calls it VP 70, the RPG names it VP70MA6). According to the RPG, these pistols were only issued to well-connected officers for ‘nearly seventy years’ (i.e. from the early 2100s to the early 2170s) but in the last decade it has become the standard sidearm, replacing the ‘outdated’ M4A3.
It’s notable that there seems to be considerable variation in how the marines carry their pistols; some attach them to their chest straps, others to their hips, while Ferro has hers in a cross-draw holster and Spunkmeyer keeps his inside his jacket. Various video games added pistols based on the Heckler & Koch M23 (the M-4A4 in Aliens vs. Predator 2), Beretta 93 (the VP78 in Aliens vs. Predator), and the Fabrique Nationale P35 (AKA the Browning Hi-Power, simply called ‘9mm pistol’ in Aliens vs. Predator Gold).
Submachine Guns
Not seen in the films, but popular in the video games and comics. The ones which seem to be common in the early 2180s are the M10 machine pistol (from Aliens: Fireteam Elite) and the M39 SMG (from Aliens: Colonial Marines). Both are manufactured by Armat (same as the M41 series) and seem to be low-velocity 9mm caseless, with magazines forward of the trigger. The justification given for these being in USCM service when the pulse rifle is already a compact, easily controlled, fully automatic weapon is that they are preferred for use aboard spacecraft, where over-penetration is a concern. They may also be more compatible with sound suppressors and allow a bit more ammunition to be carried.
Grenade Launchers and Mortars
U1 Grenade Launcher
This is the pump-action grenade launcher attachment mounted under the M41A pulse rifle. It feeds from an internal tube magazine which holds four 30✕71 mm cartridges (the props of these are only 19 mm wide, as is the barrel of the launcher, due to being made from 12-gauge shotgun parts and accessories). It has a muzzle velocity (with the M40 grenade) of 78 m/s and is accurate to about 180 m (both about the same as modern under-barrel grenade launchers).
M92 Grenade Launcher
A six-chamber revolver grenade launcher from the video game Aliens vs. Predator 2. It loosely resembles the famous Milkor Multiple Grenade Launcher (designated M32 Multiple-Shot Grenade Launcher by the US Marine Corps) and may have been inspired by the custom-built grenade launcher (actually a dressed-up AN/M5 aircraft flare launcher) in Predator. Apparently there is a blink-and-you-miss-it shot of the vaguely similar ARWEN 37 less-lethal launcher in Aliens (when Ripley is gathering weapons in the Smart Ass dropship) although I can’t really make it out clearly. Although not explicitly stated, it seems likely that it uses the same 30✕71 mm cartridge as the U1.
30✕71 mm grenades
M40 and M47 High-Explosive Dual Purpose (Red cap)
A simple explosive charge surrounded by wire (M40) or pellets (M47) which shred anyone within 5 m. In the real world, HEDP rounds use a shaped-charge to penetrate armour combined with a fragmentation shell (hence, dual-purpose is both anti-vehicle and anti-infantry). However, here the term seems to be used to mean that they can be used either in a grenade launcher or as a hand-grenade (with 5 second delay).
M38 High-Explosive Armour-Piercing (Green cap)
This is the actual shaped-charge one. It can punch through 7 cm of mild steel (about 10% more than modern 40mm grenades) and has a similar blast to the M40.
M51A Bounding Fragmentation (Blue cap)
A fancy airburst round which uses a small charge to ‘bounce’ away from the point of impact before exploding. The similar Mk. 6 High-Explosive Smart-Bounce is seen in Aliens: Fireteam Elite.
M108 Canister (Black cap)
Essentially a buckshot shotgun shell, launching a blast of pellets for close-range engagements.
M230 Baton (Yellow cap)
A less-lethal ‘rubber bullet’ for riot-control. Probably a bit safer than modern-day versions, but still capable of causing injury or even death if you’re unlucky.
T3 Tear Gas (Pink cap)
A less-lethal chemical weapon. Causes irritation of eyes and mucous membranes resulting in impaired vision and pain. Allergic reactions are extremely rare but potentially dangerous.
M60 and U4 Incendiary (White cap)
Scatters white phosphorus (M60) or quinitricetyline gel (U4), which both ignite fires and create thick clouds of hot smoke, blocking vision and thermal imaging.
M72A1 Starshell (Purple cap)
A parachute illumination round. Launched straight up, it lights a large area for 45 seconds before burning out. Given that essentially all USCM personnel carry night-vision equipment, it seems likely that this is mostly used for rescue missions.
Proximity Mine (Brown cap)
Uses a laser sensor to detect motion nearby and then detonates.
UA 571-F Automatic Grenade Launcher Sentry
One of the family of weapon systems including the UA 571-C (which uses a 10mm machine gun) and the UA 571-D (laser). It mounts a 40 mm automatic grenade launcher. No further details are given, but it seems likely that it would complement the other sentry systems by providing anti-light-vehicle firepower (while the -C handles infantry and the -D does air-defence, leaving heavy armour to be dealt with by HIMAT missiles). As such, I expect the standard round to be a shaped charge one.
M402 Multiple Launch Mortar
A ‘twin-tube’ (double-barreled) 80 mm medium mortar which feeds from a ten-round rotary magazine. It can either be mounted on a motorised base unit (which takes three people to carry and set up) or the M572 mortar carrier (part of the same family of vehicles as the M577 APC). It isn’t specified what kind of shells it fires, but a proximity-fused airburst ‘shrapnel’ round would seem consistent with its role and the setting’s general technology level.
The emplaced version is operated remotely, so the controller can stay a safe distance from the weapon in case someone shoots back. It might even have enough range that it can be operated by someone with direct line of sight to the target, acting as their own forward observer.
Hand Grenades and Mines
G2 Electroshock Grenade
The infamous ‘sonic-electronic ball-breakers’ deliver a high-voltage shock which disrupts both nervous systems and unshielded electronics within a few metres, accompanied by a dramatic ‘thundercrack’.
Smoke Grenades
Not actually described in any of the books, films, or games, but it seems certain that infantry would have some means of laying down smoke to obscure their position without risking setting themselves on fire (numerous USCM vehicles have particulate smoke dischargers, and the technical manual points out how LIDAR is easily blocked by such smoke).
Marking Flares
The flares we see used in Aliens are M-94 ones. They are small ‘pencil’ style flares, ignited by simply striking the end against a hard surface, and burn bright pink-white. I expect that there are numerous different types available in a variety of colours (including infra-red).
M20 Claymore Mine
Based on the real-world M18 Claymore mine. Unlike the M18, the M20 does not need to be detonated by remote command, but includes laser sensors which can detect nearby movement.
M5A3 Bounding Mine
A ‘smart’ anti-personnel mine which links to remote sensor platforms and triggers when suitable targets enter its kill-zone. Launches into the air, spinning, then detonates when its directional charge is facing the target.
M111 Anti-Vehicle Mine
A simple pressure-activated mine with a substantial shaped charge.
Breaching Charge
Various different explosive charges are used by the USCM. The Armat type 4 assault breaching charge is the most commonly issued to rifle squads, consisting of a block of plastic explosive sufficient to knock a metre-wide hole in most walls, attached to a detonator which can be set with a variable delay or triggered remotely.
Directed Energy Weapons
Lasers
Although lasers compact and powerful enough to function as small arms do exist in the setting (the crew of the Nostromo actually carry laser pistols early in the film, before deciding that they were too risky to use on the alien), the USCM rarely issues them, typically only for use in zero-gravity environments (per the Alien RPG books). Compared to ‘slug throwers’, their lack of penetration and tendency to overheat makes them rather ineffective.
The Colonial Marines Technical Manual list several heavier laser weapons. The largest (and the only ones seen on film) are the 80 MW (actually, the technical manual says 80 mW; it consistently gives the symbol for milliwatts when it obviously means megawatts) point-defence lasers in the Conestoga-class starships' side turrets. These are free-electron lasers, which means they can vary their frequency, but it seems likely that they operate mostly in the far-ultraviolet range (most efficient in vacuum). Apparently they are effective against small craft and missiles up to 20 km away.
The A2 version of the M577 APC mounts twin 40 MW free-electron lasers (Republic Dynamics M2025) which work in the 2-3 micron range (2-3 μm, 100-150 THz, short-wavelength-infrared - this is sub-optimal for spot size and atmospheric penetration, but maybe the best compromise which minimises retinal damage from scattered light). The usual firing mode is pulsed (total power drain apparently 10 MW for both lasers, so each laser has about a 1:15 ratio of active to inactive time) to maximise penetration (apparently this can shoot down aircraft and missiles at 1-3 km, which seems plausible for the numbers given) but there is also a low-energy (20-50 kW) ‘dazzle mode’ for blinding sensors. In general, all the APC’s rear-turret weapons seem optimised for use against aircraft and missiles, rather than ground targets (which seems fairly sensible, given how scary aircraft and missiles are in the setting).
A (presumably similar) 40 MW free-electron laser (the M820) is used as an air-defence weapon. It isn’t made entirely clear what kind of set-up that entails, but it is in the section describing air-defence artillery. It uses its laser both as a weapon and a sensor (LIDAR).
The M292A2 self-propelled gun has an air-defence laser turret. No details are given, and this may be the M820.
Finally, the UA 571-D sentry gun variant uses a 20 MW HF laser. I think ‘HF’ means hydrogen fluoride. (Experimental) HF laser weapons do exist in the real world, but hydrogen fluoride is fairly unpleasant, so I question the wisdom of deploying something like that near your own infantry. Possibly the HF is converted to something safer immediately after being used, or HF stands for something else entirely (e.g. ‘high frequency’).
Particle Beams
The USCM use both neutral and charged particle beam weapons. The former are one of the anti-starship weapons found on the Conestoga-class (the big fixed-mount guns on either side above the laser turrets - the Bougainville-class seems to have similar ones on its large dorsal turret). These are apparently ‘800 MeV’ - I think that is energy per particle (each particle seems to be effectively a deuterium atom, so if I understand this correctly, the beam velocity is around 71% of light-speed). They are about 60-80 m long, so the particle accelerators have an ‘energy gradient’ of 15-20 MeV/m, which isn’t that much compared to real-world systems. It isn’t clear exactly how many particles this thing shoots out, but their penetration and effect should be pretty impressive. The book says they can disable electronics (presumably well-hardened ones) at 100,000 km. Getting useful energy densities out of a particle beam at that range seems likely to be challenging.
Charged particle beam weapons are the main ‘guns’ of the M577A3 APC (I think this is what Hudson calls ‘independently targeting particle beam phalanx’ in the special edition of Aliens - ‘independently targeting’ could mean that each of the two accelerators can aim independently, or, more plausibly, that the system can automatically select its own targets). These are 400 MeV (firing electrons, so something like 99.9999% of light-speed) and pull power from a 20 MW generator. There is ‘some 300 kg of deuterium tankage to provide beam mass’ (I think this means the weight of full tanks, not 300 kg of deuterium, which would require several tons of tankage with modern-day technology - no idea why they use deuterium, which seems inconvenient as a source of electrons). These apparently hit harder than the M2025 lasers, being able to punch through light armour at 3 km and disrupting unshielded electronics somewhat further than that. The entire turret including the ‘barrels’ of the weapons is only about 3m long, so either the accelerators are tightly coiled (requires strong magnetic fields) or they have very high energy gradients (real-world in-development technology may be able to deliver 1,000+ MeV/m over short distances, so that isn’t implausible).
Although not described in the CMTM, these charged particle beams presumably use UV lasers to create ionised paths in the air for the beams to follow. This both allows the weapon to actually hit the target (charged particle beams are ‘self focusing’ in air, but the point of focus wanders, creating something rather like a lightning bolt or the inside of a plasma ball if not directed by a path of lower resistance) and (I think) increases the range by reducing the number of air molecules in the path of the beam (through heating the air so it expands).
One downside of particle accelerator weapons not mentioned in the Technical Manual is that they tend to ‘scatter’ ionising radiation from the beam path (and even more so from the target). While exposure will fall off rapidly with distance (both because the intensity of radiation falls with the square of distance and because air soaks up x-rays), these aren’t something you want to be using too close to your own troops, which makes them an odd choice for an APC.
Phased Plasma
The term ‘phased plasma’ is pure sci-fi technobabble, but the way that plasma weapons are described as working in the Technical Manual is, if not really plausible, not completely ridiculous. Essentially, they function much like charged particle beams, but firing ionised molecules (i.e. electrically charged gas) rather than sub-atomic particles. In this case, the use of a laser to create an ionised channels is explicit (although it then goes on to say that they are charged to form a ‘solenoidal magnetic tunnel’ which seems like nonsense). Solid pellets of ammunition (Cadmium Telluride, possibly used because it goes from solid to vapour pretty quickly at the right temperature) are vaporised by the laser and then magnetically accelerated to considerable speed along the length of the trail. The stream of gas hitting the target seems to create an effect similar to a shaped charge.
The plasma cannons on the M577A1 APC (Boyars PARS 150) are 20 MW guns powered by a 6 MW fuel cell, which can each fire once every three seconds (allowing for cooling). They shoot 5g of plasma at 5 km/s (62.5 kJ kinetic energy, about four times the energy of a modern heavy machine gun round, or less than half the energy of shells from a modern APC’s autocannon). Effective range (against an unspecified target) in ‘ideal conditions’ is 4 km. It seems like these have comparable (or even better) effect to the charged particle beams, and stronger than the M2025 lasers (but are limited by their low rate of fire and would be slightly less accurate, especially against fast-moving targets, due to projectile travel time). Given the modest kinetic energy, I think that heat and electric shock is contributing to the damage too.
A smaller plasma weapon is the man-portable M78 Plasma Infantry Gun. This is a 15 MW weapon powered by a 4 MW fuel cell, and seems to be essentially similar to the PARS 150 in operation. It is described as ‘able to breach the flank armour of a heavy tank at 1,000 m’. That would be equivalent to several inches of steel, which might be possible if the plasma stream is sufficiently focused (but focusing it would be incredibly difficult, since hot ionised gas is even harder to keep concentrated than electrons, especially when it takes something like 0.2 seconds to reach the target as opposed to a few microseconds). The main advantages of the PIG vs. missiles seem to be its large ammunition capacity (30 shots) and ability to hit faster than active-protection systems can respond (the CMTM says that engaging tanks with missiles at ranges further than 1 km is usually pointless, although there are air-launched missiles which seem to get around this with fancy counter-countermeasures tricks). On the other hand, it can only attack the side facing you (unlike the various top-attack smart missiles available to marines) and is one of the heavier individual weapons (15.2 kg vs. 3.1 kg for M83 SADAR anti-tank missile, for example) so it isn’t very popular.
The M40 Ridgeway heavy tank has a 20 kW phased plasma point-defence gun, which it uses to defend against aerospace craft and missiles. I’m not sure if the massive jump in power from the 20 MW guns to 20 kW is an error, or if this weapon is meant to be much less powerful. Since a 15 MW plasma gun seems capable of punching through tank armour, it does seem likely that something only intended for use against ‘soft’ targets would be smaller and weaker. However, if the input power corresponds to transferred energy, you’re looking at a stream of gas with kinetic energy equivalent to the very weakest pistol cartridges or a good air rifle. If focused onto a tiny spot, that may possibly be capable of penetrating a couple of mm of steel, but the damage seems likely to be slight.
The only other plasma weapon named in the Technical Manual is the M270 mobile phased plasma gun, an air-defence artillery system. Apart from being described as capable of destroying artillery shells in flight, no real detail is offered. ‘Mobile’ implies that it might be some form of self-propelled gun, maybe even an autonomous robot.
The comics and video games introduce a few other plasma weapons, but these mostly seem to appear in the 2190s or later (after the time period covered by the Technical Manual and the standard RPG setting). There are essentially no published technical details of how they work.
