Russia’s OFZAB-500 bombs: Propaganda and reality clash in Kupiansk claims

Russian forces have been using such bombs to strike Ukrainian cities since the early days of the full-scale invasion. For instance, on March 9, 2022, Ukraine’s State Emergency Service demonstrated the defusing process of one such bomb dropped on Chernihiv.

Impact of the OFZAB-500, a type of guided aerial bombs used by Russia.

The bomb contains a large amount of an incendiary mixture that destroys defensive positions. pic.twitter.com/KM2NrthJvC

— Clash Report (@clashreport) November 19, 2024

Russia is modernizing these bombs by equipping them with UMPC (Unified Planning and Correction Modules), transforming them into guided aerial bombs (GABs). Reports of these modified munitions first surfaced in April 2023.

Upgrades to the bombs do not reduce their threat, as they are hazardous thermobaric munitions. The OFZAB-500 bomb contains a solid thermobaric mixture, OM-100MI-3L, which includes isopropyl nitrate mixed with aluminum-magnesium powder. This composition is also used in handheld rocket flamethrowers like the RPO-A Shmel (man-portable, single-use, rocket-assisted thermobaric weapon).

Thermobaric weapons generate a massive explosion with extremely high temperatures and pressure, causing catastrophic damage to both personnel and infrastructure within the blast zone. The OFZAB-500 is a single-cycle thermobaric weapon, characterized by the synchronized spread of a shockwave and the intense combustion of its thermobaric mixture, reaching temperatures of 1,500–2,000°C.

Another notable feature is their ability to create a "fire cloud" capable of infiltrating shelters and destroying everything within fortifications or buildings.

Earlier, RBC-Ukraine reported that Russia may have recently used rare FAB-500T aerial bombs in strikes on Zaporizhzhia.