The Air Force on Wednesday night dropped the largest non-nuclear bomb ever developed on an Islamic State tunnel complex in Afghanistan.

Designated the GBU-43, the 30-foot, 22,000-pound guided munition is called the massive ordnance air blast (MOAB). More colloquially it is referred to as the Mother of All Bombs. The huge explosive is deployed by sliding out the back of a C-130.

A GBU-43/B Massive Ordnance Air Blast weapon on display outside the Air Force Armament Museum, Eglin Air Force Base, Fla.
A GBU-43/B Massive Ordnance Air Blast weapon on display outside the Air Force Armament Museum, Eglin Air Force Base, Fla.

A Pentagon spokesperson said the MOAB was delivered from the back of a Lockheed Martin [LMT] MC-130 special mission aircraft operated by Air Force Special Operations Command (AFSOC).

Around 7 p.m., local time in Afghanistan, the Pentagon conducted a strike against an Islamic State tunnel complex in Achin District, Nangarhar Province, Afghanistan. The weapon has a blast radius of more than a mile and a blast yield of 11 tons of TNT.

The strike was designed to minimize the risk to Afghan and U.S. forces conducting clearing operations in the area while maximizing the destruction of ISIS fighters (which the U.S. military calls ISIS-Khorasan or ISIS-K) and facilities.

“U.S. forces took every precaution to avoid civilian casualties with this strike. U.S. Forces will continue offensive operations until ISIS is destroyed in Afghanistan,” U.S. Central Command (CENTCOM) said in a statement.

Fast-tracked for Operation Iraqi Freedom (OIF), the bomb was developed by the Air Force Research Laboratory (AFRL) but never deployed in combat until now. The GBU-43 is best suited for near-surface cave and tunnels complexes and is not a deep-penetrator like the 20-foot, 30,000-pound GBU-57 massive ordnance penetrator (MOP) built by Boeing [BA].

“This is the right munition to reduce these obstacles and maintain the momentum of our offensive against ISIS-K,” Gen. John Nicholson, commander of U.S. forces in Afghanistan, said in a statement.

“As ISIS-K’s losses have mounted, they are using IEDs, bunkers and tunnels to thicken their defense,” Nicholson said.

MOAB was designed by Huntsville, Ala.-based defense contractor Dynetics, which developed the guided bomb in partnership with AFRL.

“In only three months, the MOAB preliminary concept was developed into a detailed design, fabricated, and proven by a flight test program of three successful guided flight tests conducted over a span of only 13 days,” the Dynetics website says. “MOAB was then produced and available to the warfighter during the early days of the Iraq conflict.”