Entering service in 2719, Cosara Weaponries CRB-27 very nearly became the standard medium mech of the SLDF despite production delays and competition from Blue Shot’s rival Starslayer design. Obviously the Amaris civil war put an end to that, but in its prior fifty years of service the Crab proved itself to be a reliable and dependable machine. Cheap too at a little over 4 million C-bills, which combined with its legendary toughness and ease of repair may well be why the SLDF liked it so much even though there isn’t a lot of advanced technology incorporated into the basic design.
The chassis is conventional, as is the 250 rated fusion engine that can push it along at 85 km/h - which is a respectable speed for the era - but where the Crab does dip into the Star League toy box is its shell. Nine tons of ferro-fibrous armour form the carapace, which is almost as much as can be carried by chassis. The centre torso can withstand an AC 20 burst while the side torsos can shrug off two large laser hits without going internal. Meanwhile the rear armour is characteristically strong for a Star League mech, being able to resist at least a medium pulse laser and a large laser in the centre torso. Particular attention has been paid to protecting the limbs, which all carry the maximum protection. This makes a certain degree of sense as it protects the machine's mobility and there’s only so much you can do with a 50 ton chassis, but the fact the side torsos can be shot out by three PPC hits makes me wince a bit and I would be inclined to move a little of the armour from rear plates and legs to guard against that.
For weapons the Crab sports a head mounted small laser, a medium laser buried in the centre torso and - hidden within a protective claw - a large laser in each arm. During the Star league Crabs apparently lacked proper hand actuators limiting their ability as raiders, however these were subsequently made available through upgrade kits. The reliance on lasers gives the Crab a respectable punch for its size and frees it from resupply, but keeping all that firepower frosty places serious demands on the cooling array. The Crab carries sixteen conventional heat sinks, but that’s still only enough to cover the main guns. Six of the sinks are mounted outside the engine and most of them are installed in the legs, so if you can find some water to wade through you can move and use your weapons a bit more aggressively. The other two are shared across the side torsos. If this warload has an obvious weakness, it’s a lack of flexibility. Whilst the pure energy battery certainly gives the Crab a nasty nip there’s no real crit-seeking going on, nor any ability to use alternative munitions or fire modes limiting you to slugging it out in a direct fire duel.
A final noteworthy feature is the Dalban Series K communications suite and 650 RND targeting systems. State of the art at the height of the Star League, these integrated systems harnessed limited AI to give a Crab pilot unparalleled tactical and strategic awareness.
“But wait,” I hear you cry, “is that really the best the Star League could do?” Of course not, and the Royal regiments got a brutally optimised upgrade to the basic Crab. The difference between a CRB-27 and a CRB-27b is relatively slight, they have the same engine, structure and armour and mostly the same weapons, which are laid out in the same way. All they’ve done is upgrade the large lasers to extended range models and replaced the original heat sinks with double strength models - these being laid out slightly differently with one in each arm and two in each side torso. That’s it, you could perform the upgrade easily in a mech bay if you wanted (and doubtless many techs did once the technologies became common again in the 3050s) but hoo-boy does it make a difference…
No Crab runs really hot, but this one is ice cold – oversinked even. You can take an engine hit and run around with the large lasers set to continuous beam spam and the heat gauge still won’t budge a millimetre. Even serious engine damage will hardly slow down your long ranged fire. Couple that with the extra critical padding endowed by those double heat sinks and the CRB-27b can be a serious pest to put down. Also, thanks to those extended range lasers this Crab isn’t a medium ranged fighter any more. 570 metres isn’t a massive distance, even back in the Star League, but no introtech weapon with comparable range comes without a minimum range to fuss about with and the medium and short ranged brackets mean you can try and hold favourable range increments over machines armed with PPCs and light autocannons. You also have much more concentrated damage than machines armed with the equivalent mass of long ranged missiles. Only the bleeding edge ER PPC competes well for range and firepower and how many twenty-eighth century mechs were armed with those that weren’t in the Royal regiments? In the era when it was created, facing machines that were mostly equipped with low tech weapons and heat sinks, this enemy Crab would have been a giant problem to face.
The CRB-27b was widespread enough to soldier on into the early succession wars in the service of the Free Worlds League and Capellan Confederation, where I suspect component attrition would have quickly left any survivors functionally identical to the CRB-27. However, most of these durable and effective machines left the Inner Sphere on the exodus and have served the Clans ever since. More recently the specifications of the CRB-27b were discovered in the New Dallas Memory Core and it appears that subsequently every Inner Sphere faction that still have Crabs in their ToE have refitted the majority of their extant machines to this standard.
Circa 2750, a second advanced Crab variant saw service with the SLDF. The CRB-27sl took the radical step of fitting an extra light engine, sacrificing both durability and cost for war load, but otherwise retains the armour and structure of the CRB-27. All the lasers are upgraded to their pulse equivalents except the small laser with instead is replaced with a conventional medium piece and this time there are fourteen double heat sinks. Finally, the machine gains five jump jets. Obviously this machine wants to get in your face and jump around just outside touching distance whilst cutting you up with accurate laser fire. It’s also a pretty nice scout hunter and good at fending off back stabbers, so long as you’re not asking it to chase down anything too fast. Compared to the 27b, the 27sl isn’t quite such a cool running machine, but walking alpha-strikes are still heat neutral and you’ll only have problems if you repeatedly leap around like Rudolf Nureyev while cutting loose with the entire energy battery and blaring Jean Michelle Jarre over the PA system. Also unlike the CRB-27b, the 27sl never survived in the clan toumans nor made a come-back during the Jihad so it has been extinct since the fall of the Star League. A shame – it’s a niche player but it’s a lot of fun to use.
Speaking of the fall of the Star League, the CRB-20 is what happens when you’ve got a Crab, but you can’t get your hands on Star League tech any more. The Dalban tracking and communications systems were replaced by off the shelf Garret components and the ferro-fibrous armour has been replaced with an equal weight of standard plate. Bearing in mind the ablative nature of battlemech armour, it is likely that any Crab that lasted for any length of time into the succession wars would quickly find itself reduced to the CRB-20 configuration. It wouldn’t be long before all your original armour had been blasted off and replaced and even if your Dalban systems were still operational, simply finding spare parts for regular maintenance would be a bear so replacing them with quality parts you can keep working makes sense.
In order to mount that standard armour, quite a lot of protection had to go – the equivalent to almost a full ton of ferro-fibrous plate – and it’s been removed pretty evenly across the whole chassis. A single gauss rifle hit will now go internal if it hits the arms or side torsos and centre torso armour has its protection reduced by 10%. The back plates have been slightly thinned and the legs have had their protection reduced too, although they’re still proof against a class 20 autocannon with a little to spare. All told, this is not ideal. The original Crab armour array enabled it to resist two big hits to most locations without breaching and often a third with a few points of structure left, whereas with a CRB-20 it’s quite likely that that second hit is going internal and the third will see bits of your mech falling off. I can’t help but feel they should have removed more armour from the legs and back in order to retain as much of the front facing torso armour as possible. In fact, I think I would have preferred to lose a heat sink and tried to keep as much of the original protection scheme as I could irrespective of what it did to my heat curve.
All that being said, even in this diminished form the CRB-20 is a really solid machine, in fact it’s arguably the best medium mech of the succession wars. Few of its medium weight competitors have more armour and those that do are either slower or outgunned. You’d be one of a very privileged few if you had access to one before 3039, however, as by the end of the Fourth Succession War only about a hundred Crabs were still known to be operational. Of course, Comstar managed to find a few thousand that they’d conveniently lost down the back of the sofa when it became time to provide military aid to the Draconis Combine. Officially all the machines so delivered had been downgraded to the CRD-20 standard, but apparently a few in their original configuration slipped through the net and it would not have been hard at all for the DCMS to refit the rest (minus the Dalban computers) once the Combine got ferro-fibrous armour production back on line.
Speaking of which, as the Great Houses struggled to repel the Clan invaders, a distinctively Kuritan variant of the Crab would make an appearance. A very minor variation on the CRB-27, the CRB-C merely removes the medium laser to make way for a C3 slave. It’s a pity the Kuritans didn’t come up with a more complex upgrade that could add the slave without compromising firepower, but simplicity was obviously the name of the game here and this Crab makes for a wonderfully durable point man in a C3 lance. The central position of the slave coupled with the Crab’s zombie nature means that without ECM it takes either an unlikely critical hit or the complete destruction of the mech to stop it from transmitting to the rest of its lance.
By the 3060’s the Inner Sphere had come up with some innovative ways to close the technological gap to the Clans and had Comstar devised the first really new Crab variant for a couple of centuries. The CRB-30 beefs up the armament considerably by replacing the large lasers with Extended Range PPCs and the medium and small lasers are also given the extended range treatment. A C3i computer occupies the right torso and a Guardian ECM system sits in the left, so this mech can either jam enemy electronics, set the system to counter-ECM and protect the integrity of its own network or in the absence of any other threat maybe try some ghost targeting to make itself that little bit harder to hit. In order to accommodate all this extra hardware the engine has been replaced by a 250 XL unit and two heat sinks had to be dropped, although they are now double strength freezers. This makes the CRB-30 the only Crab that can’t cover the entire heat of its two large energy cannons, however it still comes close enough that heat isn’t a major worry. Whilst it is not as durable or heat efficient as most other Crab variants, as a member of a C3i formation the CRB-30 is a really formidable and versatile tool. It is equally at home sniping at long range or taking point and thrusting into an area of network denial. It is fast enough to provide some muscle to light forces and makes an economical over watch partner for heavy formations. What it can’t do is take a really heavy beating and keep on transmitting like a CRB-C can.
Whilst the Word of Blake had access to the CRB-30, they clearly felt entitled to their own special hot-sauce version and the resulting CRB-45 is – different. The engine has been bulked up to a 300 XL model making the CRB-45 the fastest machine in the family and whilst it has the usual standard structure, this Crab elects to mess with its shell - something only the CRB-20 had previously done – and mounts Heavy ferro-fibrous armour. That sounds fantastic until you realise this was actually done to save weight and entailed a slight loss in protection. However, by skimming armour off the legs and rear centre torso, the CRB-45 manages to slightly thicken the front torso facings and gives nothing away on the arms or head so this is arguably a superior armour configuration to the standard array – certainly I’ve always felt that the classic Crabs devoted a little too much protection to the rear arc and legs.
Like the CRB-30 the 45 mounts a C3i computer in the right torso, but the armament has otherwise been completely revised. The centre line medium laser has been replaced with an extended range large model and the arms now sport light PPCs. The small laser is gone and third light PPC replaces it, although this has been moved over the left torso in order to fit in. There are fifteen double heat sinks this time, which makes this machine almost as frosty as the CRB-27b. This is the only Crab with minimum ranges on any of its guns so by extension it’s the only Crab that would to prefer to stand off from the enemy a bit. It does hit harder than any other Crab at long range so that’s not a problem, but none of the guns are really truly long ranged so it’s not the sniper that the CRB-30 is. In fact, the armament very much resembles a lot of the energy configurations sported by the Celestial series omnimechs and needs to be used in a similar manner, which means team work and movement across the C3i network making up for the lack of absolute range. Certainly, if you’ve just ripped massive hole in some poor sod with a Shootist ST-8C but they refused to die quickly, then a trio of LPPC and a Large Laser shot with C3 support from 540 metres away could be just the spice to finish the dish.
Broadly Crabs can be grouped into two sets, those with and without XL engines (incidentally, am I the only one that’s surprised that no one tried a light engined Crab?). The machines with standard engines are all legendarily tough and allow a MechWarrior to fight their way free from the battlefield even with both torsos shot out. However, because in practical terms there isn’t much variation between the CRB-20, 27, 27b and C it’s easy to declare the CRB-27b to be the pick of the bunch – it’s really just sublime so as long as it’s available and you’re not running a C3 network there is really no reason to use any other. All these machines can be a serious a PitA to deal with as you really do need to core them out to stop them fighting, although once both arms are gone they only have a relatively modest amount of firepower to offer. The XL engined Crabs are a slightly more diverse bunch, but in sacrificing durability they are much more “run of the mill” by the standards of post helm core medium mechs and strong armour aside, they are no harder to kill.
The Crab has soldiered on into the Dark ages in the armies of the Republic of the Sphere, the Draconis Combine and even the fragmented remains of the Free Worlds League. Considering how durable and effective the basic design is, I imagine it will still be with us for a good long time to come.
