The Osa-AKM (9K33M3) is a Soviet mobile surface-to-air missile system, developed by NII-20 in the early 1960s following a Council of Ministers decree (No. 1157-487). Work on the project was difficult from the start and even had to be reassigned between design bureaus. The system, codenamed “Osa” (“Wasp”), was first presented for state trials in July 1967, but the initial prototypes failed and required major revisions. Testing resumed in 1970, and by October 1971 the Osa entered service with the Soviet Army.

Almost immediately after adoption, modernisation efforts began. By 1973, two upgrade programmes were underway: Osa-A focused on improving the radar and fire-control system, while Osa-K aimed to increase the missile load to six. These were eventually merged into the Osa-AK (9K33M2), which passed factory trials in 1975 and was accepted into service. Later in 1975, development began on another modernisation to counter the growing threat of helicopters. This resulted in the Osa-AKM (9K33M3), which entered service in 1980. Compared to the Osa-AK, the AKM featured the improved 9M33M3 missile with greater manoeuvrability and reliability, revised guidance algorithms that allowed the system to effectively engage hovering and low-altitude targets, a reduced minimum engagement range (down to ~1.5 km), and improved resistance to electronic countermeasures. These upgrades made the Osa-AKM far more versatile against a wider range of aerial threats.

Throughout the 1980s, the Osa became one of the most widely exported Soviet SAM systems, entering service with virtually every Warsaw Pact member and many Soviet allies around the world. In total, 25 countries fielded the Osa, with Greece being the last to acquire it. The system saw combat in numerous Middle Eastern conflicts and remains in service with the Russian Armed Forces and several other operators to this day.

Introduced in Update 2.41 “Firebirds”, the Osa-AKM can reliably engage manoeuvring aerial targets at ranges up to 10 km and is capable of guiding two missiles onto a single target simultaneously. Thanks to its wheeled chassis, the Osa-AKM enjoys excellent mobility, allowing it to take up unexpected positions against enemy aircraft. However, the vehicle has a large silhouette, no meaningful armour protection, and its missiles are mounted at an upward angle, leaving it virtually incapable of engaging ground targets.