In recent weeks, incendiary weapons have been used with increasing frequency in the Syrian conflict. Aside from ZAB-2.5 incendiary submunitions, and white phosphorus (WP) projectiles, ZAB-100-105 incendiary free-fall bombs have also been observed within Syria.

ZAB-100-105 incendiary bomb, as seen by Human Rights Watch in Syria. Note that the bomb casing has been cut open, possibly so that rebel fighters could retrieve and reuse the incendiary composition. The white markings indicate the munition’s ballistic data.

ZAB stands for Zazhygatelnaya Aviatsionnaya Bomba, or ‘incendiary aircraft bomb’, with such weapons being used to engage a wide range of target structures, especially those housing combustible materials such as fuel and ammunition depots. Personnel, and other materiel and structures, are also potential targets for such weapons. The Soviet/Russian-produced ZAB-100-105 was introduced into the Soviet Air Forces in 1959, and has been sold and distributed to various Soviet client states, and Russian allies and trading partners in the years following. Still in service with the Russian Air Force, the ZAB-100-105 is a simple, robust free-fall incendiary weapon.

Incendiary cartridge as found by Human Rights Watch in Syria. The blue stamp reads ‘OTK 63’, which indicates the component was inspected by inspector 63 of the Technical Control Branch. It does not indicate year of manufacture or year of inspection. 

Whilst some bombs in the ZAB series are filled with a thickened synthetic fuel mixture (largely analogous to napalm), the ZAB-100-105 contains approximately 28.5kg of a solid incendiary composition (a thermite-type mixture with a binding agent) as well as nine thermite ‘cartridges’, spaced evenly within the bomb. Upon impact – as impact fuzes are almost invariably used with this type of weapon – the cartridges are ignited by the main reaction, and dispersed over the nearby area. The bomb casing is thicker as it tapers towards the nose cone, directing energy upwards and outwards upon impact, and scattering the thermite cartridges. These incendiary canisters, seen above, weigh approximately 2.7kg each, and will burn for around three minutes. Some of the larger ZAB series bombs feature a central bursting charge to disperse the incendiary filler, a feature not seen on the ZAB-100-105.

The bomb itself weighs approximately 107kg, is between 1049 and 1065mm in length, and is 273mm in diameter. The tail fins are 341-345mm in diameter. ZAB-100-105 bombs feature a so-called ‘electron’ (электрон) casing, made from an alloy of magnesium, aluminium, and zinc. The distinctive golden-bronze colour of this alloy is visible in some of the images below. These munitions are rated for deployment from heights between 300 and 12,500 metres, and at speeds from 600 – 1400 kilometres per hour. An annotated diagram of the weapon can be seen below.

ZAB-100-105 diagram taken from an official Soviet source. Annotated in English. 

The ZAB-100-105 bomb casing and cartridge featured in the photos above and below were sighted in Syria by a Human Rights Watch team, earlier this month. The bomb casing has been opened by local rebel forces, perhaps in an attempt to salvage the incendiary filler for use in makeshift munitions. The images indicate that the weapon was assembled in 1983, and the bomb casing manufactured in 1982.

There is a mistaken belief out there that the ZAB-100-105 contains a liquid (napalm-type) filler, however this is not the case. There is also very limited awareness of the presence of the nine thermite canisters within the munition. Finally, it should also be noted there has been some confusion in the media with regards to identifying white phosphorus and ZAB-series weapons correctly. I have written a brief note on the differential identification of WP and ZAB incendiary munitions.

Remember, all unexploded munitions are dangerous. You can visit RRMA for more information. As always, if you see any UXO, remember the ‘ARMS’ acronym:

•AVOID the area

•RECORD all relevant information from a safe distance

•MARK the area to warn others

•SEEK assistance from the relevant authorities

Thanks to Peter Bouckaert, Mark Hiznay, Alex Diehl, Ole Solvang, Yuri Lyamin, and Sean Moorhouse. 

Images copyright Human Rights Watch, 2012.