The Mark 84 or BLU-117 is a 2,000-pound (900 kg) American general-purpose bomb. It is the largest of the Mark 80 series of weapons. Entering service during the Vietnam War, it became a commonly used US heavy unguided bomb to be dropped. At the time, it was the third largest bomb by weight in the US inventory behind the 15,000-pound (6,800 kg) BLU-82 "Daisy Cutter" and the 3,000-pound (1,400 kg) M118 "demolition" bomb. It is currently sixth in size due to the addition of the 5,000 lb (2,300 kg) GBU-28 in 1991, the 22,600 lb (10,300 kg) GBU-43/B Massive Ordnance Air Blast bomb (MOAB) in 2003, and the 30,000 lb (14,000 kg) Massive Ordnance Penetrator.
Mark 84 bomb
An aviation ordnance technician handling the bomb body of a "thermally protected" (insulated to slow cook-off time in case of fire) Mark 84 aboard the USS George Washington
Sailors remove hoisting sling from a crate containing a pair of Mark 84 bomb bodies. Tailfins and fuzes have not yet been fitted
Mk 84 exploding in North Vietnam, 1972
A general-purpose bomb is an air-dropped bomb intended as a compromise between blast damage, penetration, and fragmentation in explosive effect. They are designed to be effective against enemy troops, vehicles, and buildings.
American AN-M64 500 lb General Purpose Bomb as seen in Boeing B-29 Superfortress weapons bay.
A 4000 lb GP bomb, 1943
A Mk 82 GP bomb loaded on an F/A-18 Hornet, showing nose fuze and textured thermal insulation
Guidance accessories for a 500 lb body and a Laser-Guided Training Round, bottom