Please enable JavaScript to view this site.

Ordnance, Explosives, and Related Items

Navigation: Ordnance > Bombs > United States

US Bomb, 500 lb Fire, Mk 77 Mod 1

Scroll Prev Top Next More

Bomb, 500 lb Fire, Mk 77 Mod 1


The 500 pound fire bomb Mk 77 Mod 1 is a 75 gallon capacity bomb obtained by modifying the 750 pound fire bomb Mk 77 Mod 0. The modification consists of cutting off approximately 2 inches from the nose and tail body sections and welding the remaining pieces together to form the smaller Mod 1. Two suspension lugs are mounted on the body 14 inches apart. Two gasket sealed filler holes are located on the upper bomb surface. The bomb is filled with approximately 72 gallons of gasoline gel. Once the bomb is filled, it can not be disassembled; it must either be used or jettisoned. Only the igniter contains an explosive burster and not the fire bomb. These bombs are used against both land and water targets.

The base color of the bomb is the natural aluminum color of the body. Purple identification bands are painted around it. Identifying nomenclature is stenciled on this modified bomb body in red letters. May also be unpainted with markings in black.

Hazardous Components

Igniters and fuzes are used in the nose and tail of the Mk 77 Mod 1 fire bomb. Three igniters may be used; the M15, the AN-M16, and the M23. The bomb is designed for primary use of the M23 igniter with the AN-M173 fuze in both the nose and the tail.

Adapters are furnished with the bomb so that the M15 igniter with the M157 fuze can be used in the nose or tail of the bomb. The M16 igniter with the M157 fuze is normally used only in the tail of the bomb, since the nose cone will not accommodate this larger igniter. If the nose cone is left off the bomb, however, the M16 igniter can be used in the nose.

Filler is napalm (450 lb, 204.5 kg)

See Also

Bomb, 750 lb Fire, Mk 77 Mod 0

Igniter, AN-M16

Igniter, M15

Igniter, M23

Nose/Tail, Impact, AN-M173A1

Side, Impact, M157


TM 9-1325-200, Bombs and Bomb Components (1966)

OP 2216, Volume 1 - Aircraft Bombs, Fuzes, and Associated Components (1960)