The GBU-27 Paveway III (Guided Bomb Unit) is a laser-guided bomb with bunker buster capabilities, it is a GBU-24 Paveway III (fitted on the warhead of the BLU-109 bomb body) that has been redesigned to be used by the F-117A Nighthawk stealth ground attack aircraft. The pilots flying over Iraq during the first gulf war nicknamed it the "Hammer", for its considerable destructive power and blast radius.
The GBU-27 was used in Operation Desert Storm. It was the weapon used in the February 13, 1991 attack on the Amiriyah shelter, which resulted in the deaths of more than 400 Iraqi civilians. It was also used in a series of strikes on the Muthanna State Enterprise site during February 1991.
During the 2003 invasion of Iraq, the US Air Force dropped 98 EGBU-27s on Iraqi targets.
The first foreign sale of the GBU-27 was the acquisition by Israel of 500 units equipped with BLU-109 penetrating warheads, authorized in September 2004. (Raas and Long 2006) Delivery of such precision guided weaponry was accelerated at the request of Israel in July 2006, though the exact munition were not specified. Israeli Defense Forces officials state that other precision-guided munitions have been used to attack Hezbollah facilities in the 2006 Israel-Lebanon conflict. However, the bunker busting technology in the GBU-27 could be directed, according to Israeli military sources, at Iran or possibly Syria.
As of 2011 the UK's RAF have also ordered the GBU-27 for use in Libya.
The GBU-27 may have a strong radioactive content (for instance uranium) as it is known that in the aftermath of the Amiriyah shelter bombing event in which two GBU-27s were used, the bunker is still found to be radioactive.