On Thursday, U.S. forces detonated the most powerful conventional weapon in the U.S. arsenal, the Massive Ordnance Air-burst Bomb or MOAB, against an ISIS tunnel complex in Afghanistan’s Nangahar Province which is just along that country’s northeast border with Pakistan. The MOAB first entered the US arsenal in 2003 during the lead up to the invasion of Iraq. Its recent employment is the first time it has been used in a combat situation.
Weighing 21,000 pounds, the satellite-guided MOAB is packed with some 18,000 pounds of a gelled slurry of ammonium nitrate and powdered aluminum detonated by a highly explosive booster. The MOAB delivery package consists of an inertial guidance system, a global-positioning system, and fins and wings for course adjustment, making it extremely accurate. Given its massive size, the MOAB is dropped by parachute from a C-130 transport plane before the satellite-guidance system takes over.
The MOAB is a follow-on to a weapon designed to clear helicopter landing zones in Vietnam, the BLU-82 “Daisy Cutter,” a 15,000 pound fuel air explosive device. The BLU-82 was also employed in the 1991 Gulf War and more recently in Afghanistan, where along with the BLU-118/B thermobaric weapon, it was used against al Qaeda troops in fortified caves.