Coral to Concrete: China Building New Facilities in the Paracel Islands

The GBU-39 Small Diameter Bomb (SDB) is a guided air-delivered bomb in the 250-pound weight class, developed and predominantly produced by Boeing in the United States. The munition entered service in 2006, and has been produced in at least three variants, with at least two different warhead configurations. The standard warhead contains 37 pounds (16.8 kg) of high explosive composition— a relatively small payload for an air-delivered bomb, intended to minimise collateral effects and enable fighter aircraft to carry larger numbers of munitions.

The GBU-39 has been used extensively by U.S. forces and allies in in recent conflicts in Afghanistan, Lebanon and Ukraine and has been described as the Israeli military’s “weapon of choice” in its bombing campaign in Gaza. The unit cost for the standard GBU-39 variant, the GBU-39/B, is given by the U.S. Air Force as $40,000 USD.