GBU-72

Weekly insights and analysis on the latest developments in military technology, strategy, and foreign policy. The U.S. Air Force has successfully completed a series of tests of a new 5,000-pound-class bunker-buster bomb , the GBU-72/B. This included the release of a prototype of the weapon from an F-15E Strike Eagle combat jet over a range associated with Eglin Air Force Base in Florida. The testing of this weapon, developed under a program variously referred to the Advanced 5,000 Pound Warhead or Advanced 5,000 Pound Penetrator, and abbreviated A5K, took place earlier this year, but the Air Force only announced the results today . The flight tests followed an earlier round of ground testing, including an arena test , where the bomb’s warhead was detonated inside an array of barriers to gather data about its blast and other effects. The 96th Test Wing at Eglin said that this was the largest such explosive test event in the base’s history but did not identify what weapon previously held that record. A picture of the arena test of the warhead for the 5,000-pound-class GBU-72/B bunker-buster bomb., USAF Outwardly, the GBU-72/B itself looks essentially like an enlarged 2,000-pound class GBU-31/B Joint Direct Attack Munition (JDAM) precision-guided bomb configured with a bunker-buster warhead, such as the BLU-109/B or the improved BLU-137/B. The latter of these was originally known as the Advanced 2000 Pound Warhead, or A2K, and you can read more about that bomb here . This 5,000-pound-class weapon uses a modified version of the GBU-31/B’s tail kit, which contains a GPS-assisted Inertial Navigation System (INS) guidance package. This new bomb differs most visibly from the GBU-31/B series in that it has a pair of long fins or strakes, one attached to each side of the bottom of the bomb’s body. GBU-31/B-series JDAMs have a set of strakes that attach to the center of the weapon. The Air Force also touted the heavy use of modeling and simulation in the development of the GBU-72, as well as to explore its projected lethality. “An advantage to the modeling and simulation to design approach used is early prototypes are production representative,” James Culliton, the GBU-72 Program Manager, said in a statement. “This helps us bring our operational test partners in sooner with eyes-on, hands-on participation, validating our design and procedures sooner while including input that improves the weapon.” “The GBU-72 was developed to overcome hardened deeply buried target challenges and designed for both fighter and bomber aircraft,” according to an official Air Force press release. “Lethality is expected to be substantially higher compared to similar legacy weapons like the GBU-28.” The GBU-28/B is a 5,000-pound-class precision-guided bunker-buster that uses a Paveway-series laser guidance system and that first entered Air Force service in 1991. These weapons were originally developed due to concerns about the ability of the BLU-109/B to reach certain deeply-buried targets in Iraq in the lead up to the first Gulf War. To help rush these weapons into service, the BLU-113/B warheads used in the first batch of GBU-28/Bs had cases that had been fashioned from the barrels of retired U.S. Army 203mm howitzers. The Air Force subsequently employed GBU-28/Bs during the NATO-led bombing campaign over Serbia in 1999, and during the early stages of the interventions in Afghanistan and Iraq in 2002 and 2003, respectively. The U.S. government has since exported examples of these weapons to Israel and South Korea. The exact capabilities of the Air Force’s current GBU-28/Bs, which now use improved BLU-122/B warheads, are classified, but the original design reportedly had the ability to penetrate through more than 150 feet of earth and at least 15 feet of reinforced concrete. As already noted, the service expects the GBU-72/B to have much better performance. A now-outdated graphic that still provides some useful perspective regarding the comparative