Bunkers and Bunkerbusting in 2030 with superhard materials at hypersonic speed

The ultimate goal of the bunker busting roadmap is to develop technologies that enable conventional explosive fills with the power of “nuclear” materials, weapons that no longer require a fuze in the explosive train as in today’s designs, and weapons with better accuracy than those utilizing the Global Positioning Space system.

For the near to mid-term (next 15 years), the roadmap emphasizes the continued development and employment of the BLU-109/113, BLU-121B/B, BLU-122, MOP, and a next-generation, hard-target munition. For the far term (beyond 2031), the roadmap specifies the development of a “high speed penetrator” weapon.

US Air Force Research is ramping up the development and integration of a hypersonic weapon.

While the future roadmap for targeting hard and deeply buried facilities must emphasize the development of technologies that support all five HDBT (Hard Deep Buried Targets) operational capability elements (detect, characterize, plan, defeat, and assess).

The High Velocity Penetrating Weapon-Conventional Survivable Ordnance Package will be designed with a warhead that will survive and function after boosted impact into a hard target. As the speed of future weapons increases dramatically, terminal guidance and control issues will grow in importance. In addition, new fuze designs will be required to ensure the weapon functions at significantly higher impact velocities than today’s gravity-fall weapons.

Following the HVPW in development of AFRL’s HDBT Capability Concept demonstrations through 2020: 2011-2018-Integrated Precision Ordnance Delivery System (IPODS); 2016-2020-Global Strike Penetrating Munition (GSPM); and 2020-Functional Defeat Munition (FDM).

The Global Strike Penetrating Munition will provide enhanced HDBT penetration (targets hardened to greater than 15,000 psi) through even faster impact velocities (up to 4,000 fps) for targets utilizing high strength and ultra-high performance concrete.

Proposals for employing the Global Strike Penetrating Munition include via Sub-Launched Global Strike Missile, an Advanced Hypersonic Weapon, the Biconic/Conventional Strike Missile, or a Long Range [Hypersonic] Strike Weapon.

As tunnels and underground facilities are continuously dug deeper in the earth and even stronger concrete is created, kinetic weapons with even greater impact velocities may be required. However, there is a point at which penetration of an HDBT will not be possible, either due to facility depth or level of hardening, or a combination of both.

The far-term Functional Defeat Weapon is a concept driven by the recognition that competition between HDBT technology and kinetic weapon technology may favor the HDBT. Still in the definition stage, this concept requires a coordinated multi-directorate / agency technology demonstrations aimed at finding, characterizing, assessing, and neutralizing HDBTs, while providing innovative techniques to exploit HDBT vulnerabilities. These demonstrations will tackle technological challenges associated with precision effect and placement, sensor data fusion / algorithms / assessment, unconventional fuzing, and novel payloads and materials. These materials may include the use of nanotechnology.

Recent breakthroughs in nanotechnology have occurred in a range of relevant specialties from materials to sensors to energetics. The implications of these breakthroughs are that improved ISR capabilities may become available to enhance location and characterization of HDBTs. Moreover, enhanced energetics and improved material properties may improve penetration and thermobaric effects especially against WMD-related materials contained in HDBTs.

Los Alamos National Laboratory (LANL) has made substantial progress in the development of nanotechnology materials designed to enhance weapon penetration / payload survivability and lethality. Scientists have made significant progress in creating core structural properties of materials through the use of nano-sized particles.

Through the development of diamond-SiC nanocomposites, LANL has developed the technology to enhance fracture toughness while maintaining superhardness.

Their efforts revealed that superhard ceramics performed better than metal alloy tips at hypersonic (greater than Mach 5) penetrations. While surviving penetration at hypersonic velocities is critical for successfully striking HDBTs, enhancing the kinetic energy and effects of the weapon is just as vital.

“Energetics is the application of technology to alter the design of power sources, propulsion and explosive combustibles. It is most commonly associated with increasing their energy density.” There is significant motivation to utilize nano-energetic materials in weapon design as these matierials have more surface area per volume than traditional powders and thus perform better when compared to larger materials. Nano-energetic materials enable increased reaction speed, resulting in faster ignition and larger energy releases in a shorter amount of time.

“Nano-energetic materials have shown improved performances in terms of energy release, ignition, and mechanical properties compared to their bulk or micro counterparts.” LANL applied these principles to foster the development of nano-explosive reactive munitions (NERM) and materials, such as Tantalum/Bismuth Oxide, incorporating high densities and high-energy
densities.

For the same explosive power, Scientists anticipate that weapons utilizing nano-energetic
materials will be comprised of up to two orders of magnitude less overall mass as conventional
weapons. In addition, energetic materials can be designed for a specific application by
controlling density and sensitivity to initiation. The Defense Threat Reduction Agency has
accomplished extensive work on advanced energetics as well. Near-term efforts include
enhanced thermobarics and shock-dispersed fuels. Mid-term efforts emphasize advanced multifunctional
energetics and all/high nitrogen species. Far-term efforts include metastable molecular clusters (5 to 50 times greater energy than conventional high explosives (HE)), nuclear spin and shaped isomers (104 times greater than HE), small-scale fusion (108 times greater than HE), and anti-matter annihilation (over 1000 times greater than HE).

Current and Future Gaps in Defeating HDBTs

Countries across the world increasingly recognize the benefit underground facilities provide in protecting and securing strategic assets. These facilities are becoming “ubiquitous,” able to conceal resources, capabilities, and intent. High on the list of nations making significant investments in underground facilities is China, whose underground tunnel network
reportedly stretches 5,000 km. China’s underground facilities are emblematic of the US HBDT defeat problem, highlighting gaps in intelligence (represented by the operational capability elements of detect, characterize, plan and assess) and weapons capability (represented by the operational capability element of defeat).

There are over 10,000 HDBT around the world and the number will greatly increase with improved tunneling technology and better and stronger concrete.

Double strike big 30,000 lb munition has been claimed to be successfully developed

Several thousand pounds of high explosives “coupled to the tunnel” (i.e., a 20,000-30,000 lb munition) would be required in order to destroy blast doors and send the required overpressure through the complex. Such an optimized penetrator weapon may penetrate 5-8 times farther than current 2,000 lb weapons. In addition, by employing the optimum dual delivery tactic, “where a second penetrator follows immediately behind the first, and boosting the penetrator velocity with a rocket motor, a depth of up to 40 meters can be achieved in moderately hard rock