Bunker buster

[1] In World War II the Luftwaffe developed a series of unguided rocket-propelled armor-piercing bombs for use against shipping and fortifications.

They had casings of high grade steel, much stronger than the typical World War II bomb so that they would survive hitting a hardened surface, or penetrate deep into the ground.

Though these bombs might be thought of as "bunker busters" today, in fact the original "earthquake" theory was more complex and subtle than simply penetrating a hardened surface.

The bombs had strong casings because they needed to travel through rock rather than reinforced concrete, though they could perform equally well against hardened surfaces.

In an attack on the Valentin U-Boat pens at Farge, two Grand Slams went through the 15 ft (4.5 m) reinforced concrete hardening[4]—equalling or exceeding the best current penetration specifications.

Devised by Captain Edward Terrell RNVR of the Admiralty's Directorate of Miscellaneous Weapons Development,[5] it had a streamlined hardened case and weighed about 4,500 lb (2,000 kg) including the rocket assembly.

Israeli F-15I fighter jets are believed to have used BLU-109s in the strikes that killed Hezbollah leader Hassan Nasrallah in Beirut on 27 September 2024.

It provides multiple delay arming and detonation times, as well as a void-sensing capability, which allows for precision activation of the fuze for 2,000-and-5,000-pound (910 and 2,270 kg) weapons to explode when they reach an open space in a deeply buried bunker.

[13] [14] The extra speed provided by a rocket motor enables greater penetration of a missile-mounted bunker buster warhead.

The non-nuclear component of the weapon is designed to greatly enhance the penetration into soil, rock, or concrete to deliver a nuclear warhead to a target.