Lockheed Martin's Miniature Hit-to-Kill interceptor is small and cheap, which could make it an attractive option to defend various platforms.
The U.S. Army has awarded Lockheed Martin a $2.6 million contract to continue development of its Miniature Hit-to-Kill interceptor, or MHTK. The service is interested in using the weapon to help troops on the ground knock down incoming artillery projectiles and small unmanned aerial vehicles, but the tiny missile, or other designs leveraging some portion of its technology, could possibly evolve to take on other roles.
The Maryland-headquartered defense contractor announced the deal in a press release on June 13, 2018. The contract also moves the MHTK out of the experimental science and technology phase and into formal development. The Army is pursuing the interceptor as one of the multiple weapons that will work with its truck-mounted Multi-Mission Launcher as part of what is now called the Extended Mission Area Missile (EMAM) program. The launcher and the rest of the complete air defense system, including a networked command and control setup and mobile fire-control radar, are part of the larger and obtusely named Indirect Fire Protection Capability, Increment 2 – Intercept, or IFPC Inc 2-I, effort.
"This award brings us one step closer to addressing a top battlefield priority,” Hal Stuart, the Force Protection Program Manager at Lockheed Martin Missiles and Fire Control, said in a statement. MHTK offers “an effective and cost-efficient solution to defeat rockets, artillery shells, mortars and other airborne targets,” he added, a mission commonly known as Counter-Rocket, Artillery, and Mortars, or C-RAM.
Lockheed Martin has been actively working on MHTK since 2012, developing the system with a combination of internal company funds and contracts from the Army. The company conducted its most recent controlled flight test, involving an interceptor with improved airframe and internal electronics, at the service’s White Sands Missile Range in New Mexico in January 2018.
Looking more like a model rocket than an advanced kinetic interceptor, at less than two and a half feet long, approximately one and a half inches in diameter, and a total weight of around five pounds, the missile is small by any definition. For comparison, this is roughly half the physical size of and more than a pound lighter than a short-range FIM-92 Stinger surface-to-air missile.
Lockheed Martin keeps the size of the interceptor down in large part by eliminating the need for a warhead. Instead, the MHTK uses its speed and precision to physically slam into its target and destroy it, hence “hit-to-kill.” The company says the missiles can defeat artillery rockets and shells, mortar bombs, and small drones, the latter of which are becoming an increasingly likely threat to American troops in potential low- and high-end conflicts.
The complete system uses a radar on the ground to spot incoming threats and cue the missile toward them. A small active seeker inside the missile then takes over to guide the interceptor into its target.
Without a warhead, and associated systems that come along with one, the interceptors themselves are relatively cheap, as well, with Lockheed Martin aiming for a unit cost as low as $16,000. This is less than half that of a Stinger missile and exponentially cheaper than the price tag on traditional short-range missiles, such as the AIM-9X Sidewinder.
The small size also expands the magazine depth of the Army’s Multi-Mission Launcher, since four MHTKs can fit inside each one of its 15 launch cells. This means one launcher alone could conceivably carry a full load of 60 interceptors, which could help the complete system have the necessary volume to have the best chance of defending against a large-scale indirect attack.
A cutaway mockup showing how multiple MHTK interceptors can fit inside a single Multi-Mission Launcher cell.
The Army also envisions fielding individual Multi-Mission Launchers armed with a mix of different interceptors that could allow them to act as layered, short-range air defense systems all by themselves. The service has already selected the aforementioned AIM-9X for more traditional short-range air defense capabilityagainst low-flying aircraft and helicopters.
With launchers networked together, each one might not necessarily have to have all the different types of interceptors though, with radars cueing certain ones to the most suitable targets. This could also give the IFPC Inc 2-I systems greater flexibility to engage targets over a wider area, as well as share information back and forth with other, larger air defense systems with more powerful and longer-range sensors. In 2017, the Army demonstrated it could engage small droneswith its long-range Patriot surface-to-air missiles if absolutely necessary.
MHTK had been competing more directly against a team made up of Raytheon and Israel’s Rafael Advanced Defense Systems, who had been offering a missile called Sky Hunter. This was effectively a modified version of the Tamir inceptor, which is the weapon at the core of the Israeli Iron Dome defense system. Iron Dome’s primary targets are also rockets and other artillery rounds.
The Army has also tested the millimeter wave radar-guided Longbow Hellfire as a possible option for the Multi-Mission Launcher. This could potentially give it a surface-to-surface attack capability, as well.
Together, the EMAM program and the Multi-Mission Launcher are both essential parts of the Army’s effort to address an increasingly glaring short-range air defense gap and emerging concerns about swarms of small unmanned aircraft. There’s always the long-standing and continued threat from mortars and larger artillery systems, as well.
With renewed concerns about future conflicts with near-peer opponents, such as Russia or China, the U.S. military as a whole has rediscovered a need to defend against possible aerial attacks and find answers to potential opponents’ advanced artillery developments. Small and non-state actors are also becoming ever better equipped in these regards, as well, especially when it comes to smaller, improvised drones.
The Army is also looking to add directed energy weapons to various units to disable or destroy certain threats, as well as improve its larger, longer-range air defense capabilities. These, along with MHTK and other systems, could potentially get blended together on the same platform for added flexibility against a wide array of targets.
A US Army briefing slide outlining the proposed mix of short-range air defense systems in the near-, mid-, and far-terms, including the Multi-Mission Launcher, directed energy (DE) weapons, and other systems.
But MHTK’s size and low price point could potentially make it, or a system derived from it, attractive both within the Army and to other U.S. military services in other formats. One of the more obvious potential applications would be looking into integrating a truncated version of the Multi-Mission Launcher onto armored platforms that can operate closer to the front lines or even smaller vehicles for more limited missions.
Depending on how quickly the seeker inside the interceptor activates and can acquire its target, it could have some utility against larger, but still low-flyingaircraft, such as gunship helicopters. It might be possible to develop a version that is still smaller, lighter, and cheaper than the FIM-92 Stinger missile that would expand the air defense capabilities available to small units. If this is the case, a man-portable type might be another possibility, with active radar guidance leaving tradition infrared countermeasures useless.
US Marines fire a man-portable, shoulder-fired FIM-92 Stinger missile during a training exercise.
In the same vein, the interceptors might be a useful supplement to point-defense systems on ships. The compact nature of the system means that it could potentially fit on almost any size of watercraft to offer additional protection against various threats.
An air-launched MHTK, or derivative, might offer a close-in option for aircraft against incoming missiles or other projectiles, too. In May 2018, the U.S. Navy announced it was interested in acquiring a “hard-kill” defense system to defend various large and increasingly vulnerable cargo and other combat-support aircraft from incoming missiles.
That service, along with the U.S. Marine Corps, has also been investigating potential ways to defend helicopters specifically against rocket-propelled grenades. Northrop Grumman has also already patented its own separate designfor just such an active protection system for low-observable aircraft.
A series of photographs from a test of Israeli defense contractor Rafael's prototype hard-kill active protection system for helicopters against a rocket-propelled grenade.
Again, a more advanced version may be able to take on more complex aerial targets at close ranges. A small, short-range missile derived from the MHTK could be an especially valuable option for internal carriage on fifth generation multi-role fighter jets, which otherwise have limited space available for self-defense weapons during strike missions that require them to operate in full stealth mode.
Lockheed Martin has already proposed a conceptual small, hit-to-kill air-to-air missile called Cuda for its F-35 Joint Strike Fighter to help expand how many targets it might be able to engage defensively while remaining as stealthy as possible. These would still be significantly larger than the MHTK interceptors.
Whatever the case, Lockheed Martin and the Army are moving ahead in developing the MHTK for its primary and important role of guarding against incoming indirect attacks and small unmanned aircraft. But hit-to-kill missile technology is clearly a growing field and there is significant potential for designs such as Lockheed Martin's MHTK to take on a wider variety of missions and offer far less expensive and compact options compared to their existing counterparts.