GBU-28

The GBU-28 was developed in 1991 during Operation Desert Storm to address a requirement for a munition capable of penetrating hardened command and control centers located deep underground. The initial production run utilized modified artillery barrels from deactivated howitzers to create the bomb bodies. The system transitioned from design to combat employment in approximately two weeks.

The GBU-28 is a laser-guided penetrator munition. The operator illuminates a target with a laser designator, and the bomb guides itself to the reflected energy. The Enhanced GBU-28 variant incorporates inertial navigation and GPS guidance to augment the primary laser system. The weapon utilizes a short-delay time fuze, which triggers detonation after the casing has penetrated the target structure. Testing demonstrated the capability to penetrate reinforced concrete and earth. Warhead options include the BLU-113, which contains tritonal explosive, and the BLU-122, which uses AFX-757 explosive housed in a casing machined from a steel alloy.

The system is operated by the United States, Israel, and South Korea. Its first combat use occurred in February 1991, when two F-111Fs dropped the munitions on the al-Taji Airbase near Baghdad. One bomb successfully penetrated a reinforced concrete bunker. During the 1999 NATO bombing of Yugoslavia, F-15Es deployed the GBU-28 against the Straževica command center. The munition was later used during Operation Enduring Freedom and Operation Iraqi Freedom. Israel has acquired the GBU-28 and utilized the weapon during operations in Gaza, including the 2021 Guardian of the Walls operation. In 2011, reports indicated technical issues regarding fuzes that caused premature detonation in some units. The United States Air Force began assessments for the GBU-72 in 2021 as a planned replacement for the GBU-28.