Place of origin United States Designed 1970 Unit cost $3,100 | Designer General Dynamics Manufacturer General Dynamics | |
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Type Low-drag general purpose bomb | ||
The Mark 84 or BLU-117 is an American general-purpose bomb, it is also the largest of the Mark 80 series of weapons. Entering service during the Vietnam War, it became a commonly used US heavy unguided bomb (due to the amount of high-explosive content packed inside) to be dropped, second only to the 15,000 pounds (6,803.9 kg) BLU-82 "Daisy Cutter" then in service and presently third only to the 22,600 lb (10,251.2 kg) GBU-43/B Massive Ordnance Air Blast bomb (MOAB) currently in service. Pilots flying the F-117 Nighthawk over Iraq during the First Gulf War nicknamed it the "Hammer" (albeit fitted with the GBU-27 Paveway III kit for use specially by the Nighthawks), for its considerable destructive power and blast radius.
Development
The Mark 84 has a nominal weight of 2,000 lb (907.2 kg), but its actual weight varies depending on its fin, fuze options, and retardation configuration, from 1,972 to 2,083 lb (894.5 to 944.8 kg). It is a streamlined steel casing filled with 945 lb (428.6 kg) of Tritonal high explosive.
The Mark 84 is capable of forming a crater 50 feet (15.2 m) wide and 36 ft (11.0 m) deep. It can penetrate up to 15 inches (381.0 mm) of metal or 11 ft (3.4 m) of concrete, depending on the height from which it is dropped, and causes lethal fragmentation to a radius of 400 yards (365.8 m).
Many Mark 84s have been retrofitted with stabilizing and retarding devices to provide precision guidance capabilities. They serve as the warhead of a variety of precision-guided munitions, including the GBU-10/GBU-24/GBU-27 Paveway laser-guided bombs, GBU-15 electro-optical bomb, GBU-31 JDAM and Quickstrike sea mines. The HGK is a Turkish guidance kit used to convert 2000-lb Mark 84 bombs into GPS/INS guided smart bombs.
According to a test report conducted by the United States Navy's Weapon System Explosives Safety Review Board (WSESRB) established in the wake of the 1967 USS Forrestal fire, the cooking off time for a Mk 84 is approximately 8 minutes 40 seconds.