incendiary bomb

military technology

Also known as: fire bomb, firebomb

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Last updated

June 29, 2026

Quick Summary

An incendiary bomb is a weapon designed to start fires. It contains an incendiary agent, such as jellied gasoline, that ignites upon detonation. These bombs are a type of conventional bomb, distinct from those that rely solely on explosive force.12

Incendiary bombs can be categorized into two main types:
* Intensive type: These use thermite, a mixture of aluminum powder and iron oxide, which burns at extremely high temperatures. The bomb casing itself is often made of magnesium, which also burns intensely when ignited by thermite, making these bombs effective at setting buildings ablaze through intense heat.2
* Napalm type: These contain a thin-walled container of napalm, or jellied gasoline. Napalm spreads over a wide area, adheres to surfaces, and burns for an extended period. This type is used against personnel, vehicles, and flammable installations. A rudimentary version of an incendiary bomb is a Molotov cocktail.2

While conventional bombs are typically propelled by gravity after being dropped, incendiary bombs are designed specifically to create destructive fires.2

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bomb
Conventional bomb types
Incendiary bombs are of two main types. The burning material of the intensive type is thermite, a mixture of aluminum powder and iron oxide that burns at a very high temperature. The casing of such a bomb is composed of magnesium, a metal that itself burns…
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Incendiary bombs are of two main types. The burning material of the intensive type is thermite, a mixture of aluminum powder and iron oxide that burns at a very high temperature. The casing of such a bomb is composed of magnesium, a metal that itself burns…
Read More

law of war
Weapons
Like nuclear weapons, incendiary weapons are not specifically banned unless used against the civilian population. It might be argued, however, that their use against enemy combatants (as opposed to military equipment) would infringe the 1925 Geneva Gas Protocol, since they could come within the prescription of “all analogous…
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Like nuclear weapons, incendiary weapons are not specifically banned unless used against the civilian population. It might be argued, however, that their use against enemy combatants (as opposed to military equipment) would infringe the 1925 Geneva Gas Protocol, since they could come within the prescription of “all analogous…
Read More

World War II
Iwo Jima and the bombing of Tokyo
…strikes at night, using napalm firebombs, were tried, with startling success. The first, in the night of March 9–10, 1945, against Tokyo, destroyed about 25 percent of the city’s buildings (most of them flimsily built of wood and plaster), killed more than 80,000 people, and made 1,000,000 homeless. This result…
Read More
…strikes at night, using napalm firebombs, were tried, with startling success. The first, in the night of March 9–10, 1945, against Tokyo, destroyed about 25 percent of the city’s buildings (most of them flimsily built of wood and plaster), killed more than 80,000 people, and made 1,000,000 homeless. This result…
Read More