|'Mech type||Inner Sphere BattleMech|
|Chassis||Hollis Mark 1A|
|Communications System||Dalban Series K/Garret T11-b|
|Targeting Tracking System||650 RND/Garret D2j|
|Heat Sinks||16 single|
Designed in 2719 during the last days of the Star League, the Crab was built as a medium-weight raider and guerrilla fighter for the Star League Defense Force. Although lacking jump jets, it possessed good overland speed and its all-energy weapons payload was suitable for long-range missions without the prospect for resupply. The Crab also boasted a highly advanced communications system, the Dalban Series K, and was built mostly with proven parts that were easy to maintain. The term "Crab walk" soon became synonymous with easy duty, since technicians spent less than half the time maintaining the Crab than with other 'Mechs of the same weight class. So popular was the Crab that many believed it was likely to become the standard medium 'Mech of the SLDF. Unfortunately the Amaris Civil War and the dissolution of the Star League put an end to any future plans for the Crab.
Less than 1,000 Crabs had been produced when the Succession Wars began. Cosara Weaponries' factory on Northwind was practically destroyed in 2786, one of many strategic targets attacked in the opening salvos of the First Succession War. Although dedicated technicians were able to keep portions of the assembly line open, producing what spare parts they still could to rebuild damaged Crabs, the technology used for both the original's advanced armor plating and communications system became lost. Designated as CRB-20 models, these Crabs were only slightly inferior to the original; with the destruction of the military infrastructure necessary for the Dalban Series K's more advanced functions to work, its replacement by lesser systems ironically became less of an issue. By the end of the Fourth Succession War 100 or so Crabs were still active in the Inner Sphere and all were CRB-20s.
Unbeknownst to many, ComStar had secreted away massive stockpiles of Star League technology and 'Mechs, including the Crab. When it came time to form their own military, original CRB-27 Crabs were used to outfit the Com Guards, while at the same time gifting downgraded CRB-20s to the Draconis Combine during the War of 3039 as part of Operation Rosebud. Concurrently, the discovery of the Helm Memory Core allowed the refit line on Northwind to start upgrading the remaining downgraded Crabs to their original specification. Unknown to anyone in the Inner Sphere was the continued existence of the Crab in the arsenal of the Clans, although by the time of the Clan Invasion these had been relegated to second-line and garrison units. Eventually Cosara Weaponries was able to restart production of the original Crab in the 3050s and brand-new variants began turning up. Among these were new CRB-30s built by ComStar, later acquired by the Word of Blake, which made use of new C3 technology; it was also rumored ComStar sold these models to the Free Rasalhague Republic. During the Jihad the Word of Blake managed to capture the Northwind factory and begin producing their own radical variant known as the CRB-45.
Weapons and Equipment
The Crab carries two RamTech 1200 large lasers, each housed in the claw and forearm of either arm. While excellent weapons, they are quite delicate with the focusing mirrors liable to be knocked out of alignment if used in hand-to-hand combat; fixing them requires the pilot to leave their cockpit and stick their head up into each arm's elbow to make the necessary adjustments. Backing up the large lasers is a Ceres Arms medium laser in the center torso, well-protected from the fusion engine and with easy access to the 16 heat sinks, and an Exostar small laser in the head, a last-resort weapon more suitable for fighting infantry and rioting citizens. Nine tons of ferro-fibrous armor provides good protection for its size as even the weakest locations, the left and right torso, can each survive a shot from a PPC. Originally lacking hand actuators, Cosara later provided a refit kit to install one in either or both arms.
The centerpiece of the Crab is its Dalban Series K communications system with an integrated 650 RND targeting-tracking system. It monitors all radio and short-wave bands to not only determine the 'Mech's exact location on a world but the approximate location of other units, friend or foe, without the use of satellites. The system was smart enough to predict enemy movements and project a path towards a given location while avoiding their notice. However, in contrast to the rest of the 'Mech, this system was extremely hard to maintain, even breaking down when not in combat. As the Succession Wars dragged on, only the most elite and prestigious mercenary and House units could maintain the system, and when the last living Series K-certified technician died it soon became a matter of guesswork.
The other notable feature of the Crab is its ejection seat, which performs in two different modes. When an explosion is imminent, the top hatch is blown off and the seat ejected up through the roof as commonly seen in other 'Mechs, with seat stabilization thrusters providing a controlled fall some 200 meters away. If more time is allowed, then the seat will instead rotate 90° and eject the pilot out the back of the 'Mech. This is a much briefer and gentler experience for the pilot, with their seat landing some 50 to 90 meters behind the Crab.
- The CRB-20 is a downgrade of the CRB-27 Crab, first sighted in 2810. The only major modifications to the design is the use of standard armor, which reduced the overall protection on the Crab, and the replacement of its electronic systems with more reliable off-the-shelf models. When ComStar gifted their Crabs to the Draconis Combine they replaced the original components with a Garret T-11b communications system and a Garret D2j targeting and tracking system. BV (1.0) = 921, BV (2.0) = 1,143
- Another Crab variant used by the Star League, the 27sl uses an XL engine with 14 double heat sinks. The large lasers and medium laser are traded out for two large pulse lasers and a medium pulse laser, and the small laser replaced by a medium laser. To improve mobility, five jump jets were added for a 150 meter jumping range. BV (2.0) = 1,309
- The CRB-30 is a complete rework of the CRB-27 Crab introduced in 3061. To start, the standard engine has been replaced with an extralight model. The CRB-30 puts this free weight to good use by replacing the twin large lasers with a pair of ER PPCs and upgrading the medium laser and small laser to an ER medium laser and an ER small laser. The standard single heat sinks have all been replaced with double heat sinks, though two have been removed, so the PPCs must use volley fire. The last part of this upgrade is the addition of a Guardian ECM suite and an improved C3 computer. BV (1.0) = 1,204 (C3: 188), BV (2.0) = 1,509
- This variant, fielded by Word of Blake and first spotted in 3070, makes use of three light PPCs and an ER large laser, turning the Crab into a direct-fire support 'Mech. The 45 incorporates 15 double heat sinks to combat all heat the machine is capable of producing, while a larger 300-rated XL engine allows speeds of up to 96 km/h. This came at a slight decrease in armor, though the use of a heavy ferro-fibrous weave helped make up most of the difference. A seemingly-standard C3i computer allows this design to share target data with other like-equipped units. BV (2.0) = 1,342
- This Crab variant uses a composite internal structure and a 350-rated XXL fusion engine to reach speeds of 110 km/h. A supercharger allows it to sprint at 140 km/h, which is good for leaving the field when its armor is breached. Main firepower comes from a pair of plasma rifles supported by an ER medium laser and an ER small laser. BV (2.0) = 1,964
These variants were introduced in various apocryphal sources, and thus far have not appeared in any canonical media.
- BSC-20 Big Steel Claw
- Described as a FrankenMech combining the shell of a CRB-20 Crab and the autocannon feed from an UrbanMech. Solaris Games duelist, Bogdan "The Steel Beast" Tubbs' Big Steel Claw mounts an AC/5 in the right arm fed from a single ton of reloads, supported by a pair of flamers in the center torso and pair of medium lasers in the left arm.
From MechWarrior Online:
- CRB-FL Florentine
- While all indications are that Judith Faber, Blake's Wrath agent Rapier, piloted a standard CRB-27 during the Battle of Tukayyid, MechWarrior Online paints a wildly different picture in their version of her 'Mech. Named Florentine, this variant is a virtual mini-King Crab, mounting an UAC/5 in each arm supported by a left-torso mounted LRM-5 and a right-torso mounted medium laser. Carrying one ton of missiles and three tons of autocannon ammunition, the Florentine's weapon loadout is made possible through use of a 250-rated XL engine and an endo steel frame.
- Night Chanter - The Night Chanter is an OmniMech that Clan Coyote developed from the chassis of the Crab.
- In German products, the unit's proper name was translated to Krabbe. The model code was accordingly changed to KRB-27.
- Plastic CRB-27 is included in BattleTech: ComStar Battle Level II
Original CRB-27 Crab from TRO:2750
CRB-20 Crab from TRO:3025 Revised
CRB-27 Crab from TRO:3050
CRB-20 Crab from TRO:3039
CRB-27 Crab from TRO:3050 Upgrade
Crab from RG:ilClan v5
A Crab in combat from The Battle for Twycross
CRB-27 Crab in combat from CCG
Concept art of the Crab from MWO
Model of CRB-FL "Florentine" from MW5:Mercs
- Technical Readout: Succession Wars, pp. 80–81: "CRB-27 Crab"
- MUL online date for the Crab
- Combat Operations, pp. 106 & 124
- Technical Readout: 2750, p. 30-31
- Technical Readout: 3025 Revised, p. 56-57
- Technical Readout: 3039, p. 258-259
- Technical Readout: 3050 Upgrade, p. 198-199
- Record Sheets: 3039, p. 122
- Combat Operations, p. 124
- Technical Readout: 3075, p. 169
- Record Sheets: 3075 Unabridged, p. 164
- Record Sheets: 3075 Unabridged - Age of War, p. 21
- Era Report: 2750, p. 135
- Record Sheets: 3050 (Clan & Star League), p. 131
- Combat Operations, p. 123
- Record Sheets: Upgrades, p. 83
- Record Sheets: 3050 (Clan & Star League), p. 132
- Recognition Guide: ilClan, vol. 5, p. 13
- Recognition Guide: ilClan, Vol. 5, p. 18
- Record Sheets: 3050 (Clan & Star League), p. 133
- MechWarrior Online
- BattleMech Manual, p. 91 Design Quirk Table - Crab Entry.
- Turning Points: Foster, p. 19: BattleMechs
- BattleMech Manual
- Combat Operations
- Era Report: 2750
- Master Unit List
- MechWarrior Online Resistance Heroes Sale Page
- Recognition Guide: ilClan, vol. 5
- Record Sheets: 3025/3026
- Record Sheets: 3039
- Record Sheets: 3050
- Record Sheets: 3050 Upgrade (Clan & Star League)
- Record Sheets: 3060
- Record Sheets: 3075 Unabridged
- Record Sheets: 3075 Unabridged - Age of War
- Record Sheets: Upgrades
- Technical Readout: 2750
- Technical Readout: 3025 Revised
- Technical Readout: 3039
- Technical Readout: 3050
- Technical Readout: 3050 Revised
- Technical Readout: 3050 Upgrade
- Technical Readout: 3075