| BLU-82B/C-130 | |
|---|---|
 A 15,000 lb BLU-82/B on display at theNational Museum of the United States Air Force | |
| Type | Air to surface conventional bomb[1](parachute retarded) |
| Place of origin | United States |
| Service history | |
| Wars | Vietnam War,Gulf War, andWar in Afghanistan |
| Production history | |
| No. built | 225[1] |
| Specifications | |
| Mass | 15,000 lb (6,800 kg)[1] |
| Length | 141.6 in (360 cm)[1] |
| Diameter | 56 in (140 cm)[1] |
| Filling | GSX Slurry |
| Filling weight | 12,600 lb (5,700 kg)[1] |
TheBLU-82B/C-130 weapon system, known under program "Commando Vault" and nicknamed "Daisy Cutter" inVietnam for its ability to flatten a section of forest into a helicopter landing zone, was an American 15,000-pound (6,800 kg) conventionalbomb, delivered from either aC-130 orMC-130 transport aircraft or aCH-54 Tarhe heavy-lift helicopter from the 1st Air Cavalry. A total of 225 were constructed.[2] It was successfully used during military operations inVietnam,the Gulf War andAfghanistan. The BLU-82 was retired in 2008 and replaced with the more powerfulGBU-43/B MOAB.
The designation "BLU" stands for Bomb Live Unit, as opposed to "BDU" (Bomb Dummy Units) used for practice. Originally designed to create an instant clearing in the jungles of Vietnam, the BLU-82B/C-130 was test-dropped there from aCH-54 Tarhe "Flying crane" helicopter. Later it was used in Afghanistan as ananti-personnel weapon and as an intimidation weapon because of its very large blast radius (variously reported as 300 to 900 feet/100 to 300 meters) combined with a visible flash and audible sound at long distances. It is one of the largest conventional weapons ever used, outweighed only by a fewearthquake bombs,thermobaric bombs, and demolition (bunker buster) bombs. Some of these include theGrand Slam andT12 earthquake bombs of late World War II, and more currently, theRussian Air ForceFOAB and USAFGBU-43/B Massive Ordnance Air Blast bomb, and theMassive Ordnance Penetrator.
The BLU-82 usesammonium nitrate andaluminum (cf.ammonal).[3]The warhead contains 12,600 pounds (5,700 kg) of low-cost GSXslurry (ammonium nitrate, aluminum powder andpolystyrene).
TheDaisy Cutter has sometimes been incorrectly reported as afuel-air explosive device (FAE). FAE devices consist of a flammable liquid, gas, or powder and a dispersing mechanism, and take theiroxidizers from the oxygen in the air. FAEs generally run between 500 and 2,000 pounds (225 and 900 kg). Making an FAE the size of a Daisy Cutter would be difficult because the correct uniform mixture of the flammable agent with the ambient air would be difficult to maintain if the agent were so widely dispersed. A conventionalexplosive is much more reliable in that regard, particularly if there is significant wind or thermal gradient.
The BLU-82 produces an overpressure of 1,000 pounds per square inch (6,900 kPa) near ground zero, tapering off as distance increases. It is detonated just above ground by a 38-inch (970 mm)fuze extender. This results in a maximum destruction at ground level without digging a crater.
This system depends upon the accurate positioning of the aircraft by either a fixed groundradar or on-board navigation equipment. The ground radar controller, or aircrew navigator if applicable, is responsible for positioning the aircraft prior to final countdown and release. Primary aircrew considerations include accurate ballistic and wind computations provided by the navigator, and precision instrument flying with strict adherence to controller instructions. Due to its extremely powerful blast effects, the minimum safe altitude for releasing this weapon is 6,000 feet (1,800 m) above ground level (AGL).
The BLU-82 was originally designed to clear helicopter landing zones andartillery emplacements in Vietnam.[4] The first use of a BLU-82 occurred on 22 March 1970, when one was dropped north ofLong Tieng,Laos duringCampaign 139.[5]
DuringOperation Lam Son 719 in 1971 25 BLU-82 bombs were dropped onNVA andPathet Lao forces inLaos. They were dropped by U.S. C-130 aircraft not only to clear landing zones, but also to strike against specific targets such as warehouses, vehicle parks, and enemy troop concentrations.[6]
South VietnameseVNAF aircraft dropped BLU-82 bombs on NVA positions in desperation to supportARVN troops in theBattle of Xuân Lộc in the last days of the Vietnam War. During theMayaguez incident, aLockheed MC-130 dropped one BLU-82 to assist U.S. Marine forces attempting to extract themselves fromKoh Tang island.[7]
Eleven BLU-82Bs were palletized and dropped in five night missions during the 1991Gulf War,[8] all fromSpecial OperationsMC-130 Combat Talons.[9] The initial drop tested the ability of the bomb to clear or breachmine fields;[10] however, no reliable assessments of mine clearing effectiveness are publicly available. Later, bombs were dropped as much for their psychological effect as for their anti-personnel effects.[11] Due to the size of the conventional blast, a BritishSAS unit that witnessed the explosion mistakenly assumed the U.S. had used a nuclear weapon and radioed back to their headquarters exclaiming, "Sir, the blokes have just nuked Kuwait!".[12]
TheU.S. Air Force dropped several BLU-82s during the campaign to destroyTaliban andal-Qaeda bases in Afghanistan to attack and demoralize personnel and to destroy cave complexes.[9] American forces began using the bomb in November 2001[13] and again a month later during theBattle of Tora Bora.[14] On 15 July 2008, airmen from theDuke Field711th Special Operations Squadron, 919th Special Operations Wing dropped the last operational BLU-82 at theUtah Test and Training Range.[15]
