The bomb was a GBU-43/B (GBU stands for Guided Bomb Unit). Its description is Massive Ordinance Air Blast (MOAB). That is what it is called in all official documents. Because of its size it was nicknamed "Mother of All Bombs." That is a nickname the troops gave it. It is not an official name.
There really isn't anything special about it. It is nothing more than a bigger, improved, more accurate "Daisy Cutter." The Daisy Cutter is a 15,000 lb. bomb. The MOAB is a 21,000 lb. bomb. The official designation of a Daisy Cutter is BLU-82/B BLU stands for Bomb Live Unit. They are both delivered exactly the same way, out of the back of a C-130. Daisy Cutters have been used when the situation is right since Vietnam. In Vietnam they were used to clear forests to create helicopter landing areas. In Iraq Daisy Cutters were used to neutralize IEDs (Improvised Explosive Devices) and to collapse non-reinforced tunnels.
Both the Daisy Cutter and the MOAB are air blast weapons. They never touch the ground. They are not bunker busters. Bunker busters penetrate deep into ground going through up to 22 feet of steel reinforced concrete before exploding. The GBU-28 was used to destroy Iraq's extremely hardened, thought to be impenetrable bunkers. Air blast weapons destroy targets through over pressure. That is why they are so good at setting off IEDs. Extreme over pressure also collapses unhardened tunnels.
The reason the MOAB was used in the area was that it was an open area filled with tunnels and covered with IEDs. It needed to be cleared before ground troops could go in. MOABs are not used in heavily populated areas. Its blast area is over a mile wide. While it is fairly precise at hitting its target, it is not precise in what it kills.
By the way, The MOAB is not the biggest air blast weapon. The Russians are reported to have one that is even bigger.
The media is making a much bigger deal over the bomb than is merited probably because it was the first time it was used and its nickname is the Mother of All Bombs. But huge air blast bombs have been used for around 50 years.
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Ret. USAF 1969-1973,1980-1996: Vietnam veteran. Aircraft maintenance. R & D, ICBM Operations.
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