“The hypersonic threat is real; it is not imagination"- Lt Gen Samuel Greaves

As evidenced by numerous media accounts and Department of Defense (DoD) senior leaders’ comments, the impact and challenges posed by hypersonic missile systems are a growing and extremely complex threat to our national interests.  Hypersonic weapons are highly maneuverable, travel many times the speed of sound, and allow for the destruction of targets anywhere in the world in less than an hour. Potential targets range from leaders of terrorist organizations to a nation’s critical command and control facilities.  In March 2018, General John Hyten, commander of U.S. Strategic Command stated before the Senate Armed Services Committee, “We [U.S.] don’t have any defense that could deny the employment of such a weapon [hypersonic missiles] against us.”

During a recent Hypersonics Senior Leader Executive Forum, Dr. Michael Griffin, Undersecretary of Defense for Research and Engineering further stated…“In the last year, China has tested more hypersonic weapons than we have in a decade…If Russia were to invade Estonia or China were to attack Taiwan tomorrow, it would be difficult to defend against their strike assets”.  The recently released Missile Defense Review acknowledges the threat associated with hypersonic technology and highlights the need for a space sensor layer to track weapons through all phases of flight.  Currently, 23 Nations have demonstrated varying degrees of expertise in hypersonic technology…a number that continues to grow daily.

Current Activities

In response to this evolving technology, DoD and specifically, the Services are developing various programs under an effort known as Prompt Global Strike.  According to Acting Secretary of Defense, Patrick Shanahan, “This is really about industrialization, not about science."  Dr. Griffin further expands on this point stating, “It is an effort to get these systems into the field in the thousands…we are going to have to create a new industrial base for these systems.”  The Pentagon's 2019 budget reflects the department's growing interest and concern, with approximately $2 billion expected to be allocated during the current fiscal year.  In addition, the funding for key hypersonic programs has also increased from $201 million in 2018 to $278 million in 2019.

The Services are approaching Prompt Global Strike in a variety of ways.  The Navy conducted its own hypersonic test during a summer 2018 wargame near Hawaii.  In the test, a destroyer fired hypervelocity projectiles featuring fins and a radar guidance system to address targets traveling at hypersonic speeds.  In theory, these hypervelocity projectiles could potentially target ships, ground targets, aircraft, and even incoming missiles.  In April 2018, the Air Force awarded work on the Hypersonic Conventional Strike Weapon under a contract valued at $928 million. This was followed by a successful bid to develop the Air-Launched Rapid Response Weapon.  Army efforts are focused on the Alternate Re-Entry System, which is essentially a maneuverable warhead that could be launched from Air Force bombers, Navy vessels, and Army launchers.  The Army has been involved in hypersonic technology for several years. In November 2011, the Army's Space and Missile Defense Command successfully launched an Advanced Hypersonic Weapon (AHW) from the Pacific Missile Range Facility in Kauai, Hawaii to the Ronald Reagan Ballistic Missile Defense Test Site at the Kwajalein Atoll, Republic of the Marshall Islands.

In addition, the Defense Advanced Research Projects Agency (DARPA) in conjunction with industry partners is working on a hypersonic tactical boost-glide weapon.  The defense industry is also involved in DARPA's Hypersonic Air-breathing Weapon Concept competition and possibly developing a sea-launched boost-glide capability for the Navy.

It is also important to highlight the offensive and defensive aspects of hypersonic weapons.  On the one hand, this technology provides a nation with the ability to quickly strike time-sensitive targets at great range. On the other hand, it presents many challenges defending critical assets from incoming hypersonic weapons.  From a deterrence standpoint, hypersonic weapons have value when incorporating both offensive and defensive capabilities. Potential adversaries will likely think twice before employing hypersonic weapons against a nation that possesses both a credible defense and the ability to respond offensively.

Currently, much of DoD's funding for hypersonic weapons is going toward precision strike or offensive weapons, as opposed to missile defense programs.  According to Mike White, the Pentagon's assistant director for hypersonics, "If you look at the portfolio and the time phasing on the portfolio, we are stepping out first on the offensive side as we study and assess the path forward to get a robust defensive strategy."  Part of the reason is that offensive systems are technically easier and cheaper to develop.  According to Bill LaPlante, senior vice president at MITRE, "The defense, in general, is getting harder and more expensive than the offense."

Hypersonic Imperatives

The challenges of defending against hypersonic weapons have been discussed in many academic and defense industry forums, as well as in media coverage.  The impact of speed, extreme altitude changes, and maneuverability especially during the final phase of flight, present both offensive opportunities and defensive obstacles.  From a missile defense perspective, the lack of a "universal" interceptor to address the myriad flight profiles highlights the challenges associated with hypersonic weapons. To address this threat in a sustained and cost-informed manner, agreement on hypersonic imperatives must be achieved.  To meet the services' multi-domain requirements, the following imperatives must be considered from a joint missile defense perspective.

1. The need for a "space sensor layer," now known as the Hypersonic and Ballistic Tracking Space Sensor (HBTSS), is viewed by many as one of the most immediate and critical requirements to address hypersonic threats.  Given the limitations of line-of-sight terrestrial sensors, defense department leaders have frequently lamented the challenges of tracking threat vehicles through all phases of flight.  Currently, the Missile Defense Agency (MDA) and other organizations are actively engaged in HBTSS's concept design phase to detect and track emerging (and evolving) threats using persistent infrared sensors. On-orbit sensor options, like HBTSS, will significantly enhance our engagement opportunities and probabilities of success.  Additionally, future architectures must include the integration of both space-based and terrestrial sensors to permit on-orbit track processing, while reducing reliance on ground stations and the associated time implications. Finally, the timely "reseeding" of on-orbit assets will be critical to achieving the necessary levels of resilience and redundancy.

2. Our current fleet of joint interceptors are limited in range, altitude, and the ability to defeat evolving threat systems.  In fact, the majority of our current interceptors are primarily focused on the terminal phase of flight.  Only the Ground-Based Midcourse Defense Interceptor (GBI) and to a limited degree, the AEGIS Standard Missile interceptor provide mid-course defense opportunities.  Although a “universal interceptor” may be cost prohibitive or currently technologically unfeasible, two or three interceptor classes could be upgraded to cover potential gaps as an interim solution.  In addition, DOD must leverage promising kinetic and non-kinetic options to address the ever-creasing advances in hypersonic technology. For example, the linking or “talking” of future interceptors to on-orbit sensors (and other interceptors) will significantly enhance our ability to defeat new and sophisticated threat systems.  This expanded capability will also assist in addressing many of the services’ multi-domain challenges.

3. The development of an effective and responsive Battle Management Command, Control, and Communication and Intelligence (BMC3I) system has long been the goal of the air and missile defense community.  BMC3I allows the warfighter to plan, execute, control, and sustain combat operations, especially in response to complex environments (e.g., raids of threat missile systems).  Given the speed, maneuverability, and the unpredictable nature of hypersonic weapons, current BMC3I systems are likely to be quickly overwhelmed. In response to these challenges, changes are required to shorten response times by exploiting autonomous BMC3I activities.  Again, our BMC3I systems must be capable of processing and directing engagements more quickly than our current C2 ground station construct. Ideally, the goal is to achieve an effective layered defense while minimizing gaps in coverage and providing opportunities for re-tasking of incoming targets (e.g., Shoot, Assess, Shoot).

4. Related to BMC3I is the issue of integration or the assimilation of sensors and shooters to optimize the capabilities of individual AMD systems. The introduction of hypersonic weapons further accentuates the need to fully exploit the capabilities of our current and future missile defense systems.  Any discussion of integration must also include non-kinetic options like directed energy (DE), cyber, and electronic warfare (EW) that expand our ability to attack threat systems in all phases of flight, especially during the boost phase. In addition to potential cost savings, non-kinetic options have been successfully tested at White Sands Missile Range against unmanned aerial vehicles and indirect fire munitions.  The Navy has incorporated DE capabilities in its ship defense operations. In addition to extreme speeds and maneuverability, hypersonic weapons operate in a wide spectrum of altitude regimes, ranging from very low to exo-atmospheric. As mentioned, the lack of a “universal” interceptor capable of operating in multiple altitude regimes and over extended ranges, both at sea and over land, highlights the need for integrated missile defense.  Unfortunately, many of our AMD systems were developed without stringent (and enforced) standards to fully integrate with other systems. Future efforts must address this lack of oversight.

5. As we all know, there are many claimants for finite DoD resources. The continuing challenge for the department is to balance readiness requirements with the need to   The challenge is further exacerbated when dealing with highly complex weapon systems and the issue of obsolescence. The introduction of hypersonics from both an offensive and defensive perspective, stresses the importance of modernization and the development of new technologies in response to emerging threats.  For AMD operations, the cost-per-intercept continues to be an area of concern, especially when dealing with threats requiring multiple interceptors to achieve an acceptable probability of success (e.g., probability of kill). In response to this dilemma, senior leaders are appropriately considering both doctrinal and technology solutions.  From left of launch discussions to materiel solutions addressing all phases of flight, DoD is evaluating many options to address the threat of hypersonic weapons. Bottom line: future AMD systems must provide warfighters with responsive, flexible, and integrated systems in a sustainable manner.