GATOR Mine System

The GATOR mine system is a US system of air-dropped anti-tank and anti-personnel mines developed in the 1980s to be compatible with existing cluster dispensers. It is used with two dispenser systems—the Navy 500 lb CBU-78/B and the Air Force 1,000 lb CBU-89/B. Additionally the mines are used with the land- and helicopter-based Volcano mine system.

In use the bombs are dropped from aircraft flying at speeds between 200 and 700 knots, and at altitudes of between 100 and 1,200 meters. A fuse in the FMU-140B controls the opening of the dispenser at one of 10 predetermined altitudes between 90 m and 900 m using a doppler ranging radar or alternatively a 1.2 second time fuse. Mine arming begins when the dispenser opens with the activation of the mines' vanadium pentoxide batteries. The circular mines have a rectangular plastic "aeroballistic" adaptor. Once the mines reach the ground they arm in between 1.2 and 10 seconds.

The mines self-destruct after a preset time which can be set to 4 hours, 15 hours or 15 days. Any that do not will become disabled after 40 days when the batteries discharge fully. The self-destruct time is set just prior to aircraft takeoff using a simple selector switch on the dispenser. During the Gulf War the dud rate for this system was significant, in one of seven Kuwati battlefield sectors there were 205 BLU-91 and 841 BLU-92 duds. Given that 89,235 BLU-91 and 27,535 BLU-92 mines were used during the Gulf War, this represents a dud rate of somewhere between 0.5 to 2% for the BLU-91 and to 6 to 21% for the BLU-92 . Additionally, CMS mine field clearing personnel reported dud GATOR mines detonating with no apparent triggering event, and speculated that the extreme heat of the Kuwait desert may have triggered detonation.

The GATOR system provides a means to emplace minefields on the ground rapidly using high-speed tactical aircraft. A typical GATOR minefield is 650 m long and 200 m wide and contains 432 anti-tank mines and 132 anti-personnel mines. The minefields are used for area denial, diversion of moving ground forces, or to immobilize targets to supplement other direct attack weapons. In the 1991 Gulf War the US Air Force employed 1,105 CBU-89s. One reported task was to hamper the movements of Iraqi Scud missile launchers.