Thermobaric Weapons Explained, How They Work and Who Fields Them

Thermobaric weapons generate a longer, hotter pressure wave than conventional explosives by burning dispersed fuel with the surrounding air, and Russia’s 24-tube TOS-1A is the most heavily used system of the type in service today. Fielded from shoulder-fired rockets to heavy glide bombs, these munitions are neither new nor banned, but their effects in enclosed spaces make them among the most scrutinized weapons in modern war.

24

Rocket tubes on the TOS-1A launcher

220 mm

TOS-1A rocket caliber

~6 km

TOS-1A stated range, manufacturer figure

2002

US BLU-118/B combat debut in Afghanistan

How do thermobaric weapons work

A conventional high-explosive warhead carries both fuel and oxidizer in one solid charge and releases its energy in a microsecond spike. A thermobaric charge instead carries fuel rich in metals such as aluminum and draws much of its oxygen from the surrounding air. On detonation, the fuel disperses and burns through the air around the target, producing a lower peak but far longer-lasting blast wave and intense heat.

That sustained overpressure is what makes the type effective against bunkers, caves, trenches and buildings: the pressure wave flows around corners and through openings, and in enclosed spaces the effects are severe for anyone inside. Older two-stage fuel-air explosives work on the same principle with a separate dispersal and ignition sequence, while modern single-charge thermobarics are more compact and reliable.

Thermobaric vs conventional explosives

Thermobaric vs conventional high explosive

Characteristic	Thermobaric	Conventional HE
Oxygen source	Mostly atmospheric air	Contained oxidizer
Blast profile	Lower peak, much longer duration	Sharp, brief peak
Thermal effect	Large sustained fireball	Brief flash
Best targets	Enclosed spaces, fortifications, personnel	Structures, armor, point targets
Limitations	Degraded by wind, rain and thin air; poor against armor	Less effective around corners and in tunnels

Simplified comparison; exact effects depend on warhead design and environment.

TOS-1A Solntsepyok explained

The TOS-1A, nicknamed Solntsepyok or “scorching sun,” mounts 24 tubes for 220mm thermobaric rockets on a T-72 tank chassis, a pairing that signals its role: it fires from just a few kilometers behind the front, inside artillery range, so it needs armor. Russian industry states a range of about 6 km for the improved rockets, with newer munitions claimed to reach 10 km or more, figures that remain manufacturer claims. Russia classifies it as a “heavy flamethrower system” and assigns it to radiological, chemical and biological defense troops, a doctrinal quirk dating to its Soviet origins.

A wheeled successor, the TOS-2 Tosochka, trades armor for mobility and longer claimed range. At the lighter end of the Russian inventory sit the RPO-A Shmel shoulder-fired rocket and thermobaric warheads for RPG-7 launchers, while ODAB-series aerial bombs, now fitted with glide kits, deliver the largest effects.

Which countries have thermobaric weapons

Notable thermobaric systems by country

Country	Systems
Russia	TOS-1A, TOS-2, RPO-A Shmel, TBG-7 rounds, ODAB glide bombs
United States	AGM-114N Hellfire, SMAW-NE rocket, BLU-118/B bomb
China	PF-97 shoulder-fired system and rocket warheads, per reported data
TOS-1A export users	Iraq, Azerbaijan, Armenia, Kazakhstan and Algeria, as reported
Others	Various thermobaric grenades and rocket warheads in many arsenals

Holdings per public reporting; most countries do not itemize thermobaric stocks.

The US arsenal illustrates the Western approach: niche munitions for specific targets, such as the AGM-114N metal-augmented-charge Hellfire used against buildings and the BLU-118/B dropped on Afghan cave complexes in 2002, rather than massed launchers. Russia is the only power that built a dedicated armored thermobaric artillery branch.

Thermobaric weapons in Ukraine

TOS-1A use in Ukraine has been extensively documented by open-source investigators since 2022, including in urban assaults such as Mariupol, and Ukraine has captured and reportedly operated at least a handful of the launchers itself. Russian state media credit the system with breaking fortified positions, claims that should be read as such. The launcher’s short range has proved costly: numerous TOS-1As have been destroyed by artillery and loitering munitions, losses that are operator-reported on both sides.

Russia has also scaled up ODAB thermobaric glide bombs delivered by aircraft from standoff range, part of the same glide-bomb campaign that reshaped the front in 2024 and 2025. Against that backdrop, Western militaries have mostly doubled down on precision rather than blast mass, using systems like GMLRS-armed launchers to hit fortifications with accuracy instead of area pressure.

Editor’s read

Thermobaric weapons occupy an uncomfortable space: legal in themselves, devastating in enclosed spaces, and heavily used in a war where the line between fortification and apartment block keeps blurring. The TOS-1A’s Ukraine record cuts both ways, effective enough that Russia keeps building them, vulnerable enough that drones keep killing them. Expect the type to migrate toward standoff delivery, because the launchers that must get close increasingly do not survive.

Thermobaric weapons frequently asked questions

What is a thermobaric weapon?

A munition that disperses and burns fuel using atmospheric oxygen, producing a longer-duration blast wave and intense heat, especially effective in enclosed spaces.

Are thermobaric weapons banned?

No treaty specifically bans them. Like all weapons, their use is governed by international humanitarian law, which prohibits indiscriminate attacks on civilians.