Source: Ministry of Defense of Ukraine
In all, the Ukrainian Army obtained a total of 108 examples of the vehicle shown here, the 48-ton Polish AHS Krab 155mm Self-Propelled Gun (SPG). As part of Poland's military aid to Ukraine, the country provided the first 18 vehicles which were received by the close of 2022. The remainder were obtained via purchase orders with Poland. The ArmatoHaubica Samobieżna (AHS; Self-Propelled Gun-Howitzer) Krab (meaning “Crab“ in Polish) is a joint development by the Polish company Huta Stalowa Wota (HSW), the British firm BAE Systems, and the South Korean entity Samsung Techwin. Work began on the Krab in 1997 and it finally entered production in 2016 with Polish artillery units receiving the Krab soon after.
Samsung Techwin's contribution to the Krab is the PK9 chassis which is a variant of the chassis used by the South Korean K9 Thunder 155mm Self-Propelled Howitzer (SPH). Power comes from a MTU Friedrichshafen GmbH built MT881 Ka-500 8-cylinder, water-cooled diesel engine that develops 1,000 horsepower. This is paired to a Allison X1100-5A3 transmission with a 6-speed gearbox (4 forward, 2 reverse gears). On roads, the Krab can top out at 37 miles per hour while offroad, in favorable terrain, up to 19 miles per hour can be achieved. Enough onboard diesel fuel is carried to provide for a maximum operational range of 250 miles. The all-welded chassis uses tempered steel armor plating produced by the Australian company Bisalloy with a maximum thickness of 19mm. This provides the approximate equivalent to STANAG 4569 Level 4 protection which means the armor is capable of withstanding up to and including 14.5x114mm API (Armor Piercing Incendiary) ammunition at a minimum distance of 200 meters as well as shrug off 155mm artillery shell fragments as close as 25 meters. Of the five man crew, only the driver sits within the hull.
The Krab's turret is much the same as that used on the British AS-90 155mm SPH which had been designed by Vickers Shipbuilding & Engineering, a division of BAE Systems. Like the hull, the turret supports the same Bisalloy armor and offers the identical STANAG 4569 Level 4 protection for the four men within. Situated within the turret is a HSW license built 155mm L/52 gun-howitzer. The gun mount provides for up to 70 degrees of elevation and 3.5 degrees of gun depression while the turret can fully traverse 360 degrees. The gun-howitzer uses a sliding block breech and there is a power loader which permits a burst fire rate of 3 rounds in only ten seconds. For three minutes, the Krab can fire 6 rounds for each of those minutes. A sustained fire rate is 2 rounds per minute. All told, the Krab holds 29 projectiles and 28 powder charges in the turret while the hull holds an additional 11 projectiles and 20 charges. The Krab can utilize any NATO compliant 155mm projectile to include the M982 Excalibur extended range, guided projectile. The latter can attain a range of 25 miles. A typical base bleed projectile can reach a maximum range of 19 miles. The gun-howitzer enjoys the benefit of a ZZKO Topaz FCS (Fire Control System) which consists of an automatic aiming system, ballistic computer, laser rangefinder, and both commander and gunner sights interlinked into the FCS. Outside the turret, situated on top of the gun mantlet, is a MVRS-700 SCD ballistic radar to measure the velocity of shells as they leave the barrel. In case of electrical failure, the turret can be manually traversed while the gun can also be manually elevated and depressed as well as loaded by hand. Also, should the Krab find itself in dire straits, it has a gunner's sight to allow it to engage in direct fire. For anti-air and local defense, the Krab can be fitted with a pintle mounted 12.7mm heavy machine-gun on the turret top.
Other protective systems within the Krab include an automatic fire detection/suppression system while there is a filtered ventilation system that gives a measure of crew protection against biological, chemical, and radioactive substances and agents. The Krab also utilizes the OBRA-3 SSP-1 warning and self-defense system. This consists of external sensors which detect lasers that are “painting” the Krab. Such lasers are often utilized by anti-tank missile systems. The OBRA-3 will warn the crew and designate the direction the laser is coming from. In addition, the OBRA-3 is tied into the Krab's two banks of 81mm dischargers, each bank with four launch tubes. These banks are located on the turret front, one bank on each side of the gun barrel. The OBRA-3 can be set to automatically launch smoke grenades to obscure the Krab and interfere with the laser designator or if desired, the commander can manually trigger the grenades.
Other systems include a FONET internal communication system for the crew (made by the WB Group), a RRC 9311AP RF digital radio station, FIN 311OL land navigation system, DD-9620 terminal for providing targeting data, GPS system, day/night sights for the commander and driver, and a 5.5 kilowatt output auxiliary generator (for powering the Krab with the engine off).
The Krab shown here belongs to Operational Strategic Group Dnipro, likely within Tactical Group Kharkiv or Tactical Group Starobilsk which are the group's two subordinate units. The crew has added metal mesh anti-drone screens to the turret, decking, and hull sides. Cutouts have been made in the frontal turret screens to accommodate the 81mm grenade launchers. The Krab looks to have kept its original Polish Army camouflage paint pattern.
As of September 9, 2025, the visually confirmed Ukrainian AHS Krab losses stand at 41. Of these, 35 have been destroyed beyond repair with the remaining 6 having suffered damage of varying severity.
