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Cellular Ammunition Storage Equipment

Cellular Ammunition Storage Equipment (CASE)
Production information
Type Equipment (Physical Enhancement)
Tech Base Clan[1]


Year Availability Clan = 2825

IS = 3036[1]

Year Introduced Clan = 2825 CSJ

IS = 2452 TH[2]

Year Extinction IS = 2840 [1]
Year Reintroduced IS = 3036 DC[1]
Technology Rating D
Availability Ratings C/F/D
Technical specifications
Heat 0
Tons Clan = 0

IS = 0,5

Critical Slots Clan = 0

IS = 1

Cost (unloaded) 50,000
BV (1.0) C
BV (2.0) C


CASE, short for Cellular Ammunition Storage Equipment, was created by the Terran Hegemony as a prototype in 2452 and as a production version in 2476[1][3] as a system designed to reduce the hazards of carrying volatile or explosive equipment, usually ammunition. CASE is essentially a specialized container structure for housing the equipment, and redirects explosive force in the event that the equipment explodes. While this makes it invaluable for preventing excessive internal damage, CASE does not actually stop the explosion, it merely contains and redirects the explosive force, so after an explosion units likely will be crippled or nonfunctional, though not destroyed outright.[1][4][5] Prototype CASE (CASE-P) had a tendency to not actually react to stop an explosion in some cases and has a 20% chance to not actually stop and redirect an explosion due to a variety of flaws in the system. [2]

Inner Sphere CASE weighs half-a-ton per piece, while Clan CASE does not require any additional tonnage. Both the Inner Sphere and Clan CASE cost 50,000 C-Bills. CASE mounted on an Inner Sphere 'Mech can only be placed in a torso section, and only protects that torso section. Any other ground, sea, or air vehicle mounting CASE only requires one, which protects the entire vehicle.[1][4][5]


CASE overall protects the Mech, however it does not contain, or otherwise negate the damage of an explosion in the same way CASE II is capable of. When an ammo load is detonated, apply all damage of the loaded ammo to the area affected. If the location containing the ammo isn't protected by CASE, and the damage exceeds the Internal Structure value of the location where the detonation takes place, the remaining explosion damage will transfer towards the torso of the mech whilst destroying the affected location. So, for example, an explosion in the left arm will transfer to the left torso of the 'Mech assuming that the remaining ammo there would deal damage in excess of the remaining internal structure value of that arm. If that location isn't protected by CASE and damage destroys the left torso in the transfer from the arm, then the remaining damage will transfer to the center torso, until the 'Mech is destroyed, or the damage is dissipated.

A unit with CASE mounted can reduce the damage taken from an ammunition explosion. Any time an ammo explosion enters a location with CASE, the damage will be applied as normal, but the excess damage, if applicable will not transfer to the next location. If using the example above, an ammo explosion occurs in the left arm, destroying it. The damage will spread to the left torso, but this time the left torso mounts CASE. Regardless of how much excess damage remains after destroying the left torso, the damage cannot transfer to the center torso as the CASE vents the explosion, saving the 'Mech from total destruction.

Unfortunately, Inner Sphere CASE can't be mounted in the arm or leg of a 'Mech. Clan CASE is automatically mounted on all units however, and is included, even in ammo bins in the arm or leg of a 'Mech.[6]

Inner Sphere CASE weighs half a ton and takes up one critical slot. Clan CASE is presumed to be mounted in all Clan 'Mechs unless otherwise noted, with no weight or critical space required.

Combat vehicles are notably different, when mounting CASE. Instead of location based damage in the event of an explosion, based on where the ammo is mounted, unlike a 'Mech when a combat vehicle suffers an ammo explosion all the ammo goes off in the vehicle at once. This explosion is nearly guaranteed to destroy the unit as it applies damage to their respective internal structure location where the critical causing damage was taken. If a combat vehicle mounts CASE however, all the damage caused by the explosion is vented out the back of the unit, simultaneously destroying the rear armor, but will not damage internal structure. This will stun the crew however, akin to how a 'Mech pilot would take damage due to the explosion feedback.[6][7]


  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 TechManual, p. 210, "Cellular Ammunition Storage Equipment (CASE)"
  2. 2.0 2.1 Interstellar Operations, p. 71, "CASE-P"
  3. Interstellar Operations, p. 71, "CASE-P"
  4. 4.0 4.1 Technical Readout: 2750, p. 12, "CASE"
  5. 5.0 5.1 Technical Readout: 3050, p. 221, "CASE"
  6. 6.0 6.1 Total Warfare, p. 133-4 , "CASE"
  7. Total Warfare, p. 193 , "Vehicular Critical Hits"