There is debate regarding the penetration capabilities of the bomb. The US Air Force has said that the GBU-57 can penetrate up to 60 m (200 ft) of unspecified material before exploding. The BBC reports that analysts at Janes say the weapon can penetrate about 60 m (200 ft) of earth or 18 m (59 ft) of concrete. This is consistent with a separate source which suggests penetration of up to 18 m (59 ft) into reinforced concrete with a compressive strength of 5,000 psi (34 MPa) and 2.4 m (8 ft) into 10,000 psi (69 MPa) reinforced concrete.