Navy To Supersize Its Ultra Versatile SM-6 Missile For Even Longer Range And Higher Speed
The SM-6 is getting a way bigger rocket motor that will allow it to reach even farther than before and enemy ships may be its primary target.
The Navy's SM-6 missile has become an all-star of multi-role capability and a shining example of how repackaging existing systems with some new tech can garner grand results. The missile can shoot down air-breathing threats like aircraft and cruise missiles, it can swat incoming ballistic missiles in the terminal phases of flight, it can attack sea targets, and it even has a latent land attack potential. It is also network enabled and can engage targets well beyond the sensor reach of its launch platform using telemetry data-linked from a third-party platform, like a jet fighter. It does all this over long ranges, reaching out over 150 miles from its vertical launch cell aboard American destroyers and cruisers. Now, according to 2020 budget request documents, this versatile missile is set to get upsized for considerably more range and speed, and that is a very big deal.
The SM-6 was originally designed to leverage existing components, most notably the airframe of the SM-2ER Block IV Standard Missile and the seeker from an AIM-120C AMRAAM air-to-air missile. It has quickly evolved to be more potent and flexible since its introduction into service in 2013. Now, the latest SM-6 derivative is slated to shed its legacy airframe, one which doesn't take advantage of the full diameter of the launch cells in the Navy's Mk41 vertical launch systems, and be redesigned with a 21 inch diameter motor that will substantially increase the type's range and speed.
This same approach was taken with the SM-3 anti-ballistic missile interceptor, which is used for mid-course intercepts of ballistic missile threats. That missile also evolved from the SM-2ER Block IV, but as a joint U.S.-Japan weapons program venture. The SM-3 Block IIA is a redesigned variant that uses a 21 inch motor for increased range, higher speed, and thus greatly improved capability overall. Part of the redesign also included decreasing the size and reconfiguring the missile's tail fins, and drastically decreasing the size of the airframe strakes, so that it can still fit its wider diameter frame into the confines Mk41 cell.
We had proposed that the SM-3 Block IIA's redesign be carried over to the SM-6 in a past article of ours, which now seems to be the case according to the Pentagon's proposed 2020 budget. Known as the SM-6 Block IB, the initiative looks to spend hundreds of millions of dollars over next four years to develop the more capable missile. The line-item description, posted below, makes special note of the fact that the program will leverage existing missile technology and will result in an SM-6 with increased range. It will use a 21 inch diameter motor like the SM-3 Block IIA and will leverage internal components from the SM-6 Block IA. This will likely leave the upper seeker-warhead section of the missile the same diameter that it currently is, with the larger 21 inch motor attached below. As such, it will have a "necked-down" rifle bullet like appearance.
The documents state the SM-6 Block IB is planned to make it through its primary development by 2024.
By the end of this development process, the Navy will have all of its DDG-1000 Zumwalt class destroyers operational, ships which could really use such a versatile weapon for multiple applications and especially to overcome its radar/combat suite's deficiencies. Equipping the stealthy ships with SM-6 would also vibe with the Navy's revamped vision for them.
The first FFG(X) frigates will also be delivered. The FFG(X)s aren't officially slated to receive the SM-6 at this time, but such a versatile weapon could give the small surface combatants immense reach and a heavy punch. This is also when the Navy will be introducing its first Flight III Arleigh Burke class destroyers—the latest in the class of multi-role surface combatants that the SM-6 was primarily designed for.
The Navy's new drone ship initiative—which will include vessels equipped with Mk 41 vertical launch systems—will be well underway by then, as well. They represent what is really the most exciting aspect of the SM-6, and especially a longer-range version of it. It's a networked-enabled weapon that can use third party targeting—such as that from aircraft, ships, satellites, and land-based sensors—to engage enemies over very long distances.
In other words, it doesn't really matter what the launch platform is, or to some degree where it is, in order to be employed successfully. For instance, if a Super Hornet's air-to-air missile stores run dry, an SM-6 could be launched from a ship a hundred miles away at an aerial target that is in the shadow of the ship's radar horizon or even beyond its detection range as a whole. It would use the Super Hornet's targeting data to get within range on its own active radar seeker. Once it is locked on organically, the target has a very low chance of survival.
So even if an FFG(X) doesn't have the radar capable or targeting threats at the ranges a SM-6 Block IB could reach, it could simply act as the remote launch platform if it is closest to the target and is equipped with the missile. The same can be said for pretty much any ship with a vertical launch system capable of firing the missile, such as a drone ship.
But here is the thing, by most indications, the SM-6 Block IB would be a multi-function missile like the Block IA, yet in some past documentation, the Block IB was highlighted as a long-range anti-ship ballistic missile, above all else. We don't have a range increase for the new missile design, but let's just throw out a number of 30 percent. That would take the missile's range up to roughly 200 miles, but that's based on an anti-air engagement. It would be longer in a surface-to-surface one. And this is a very conservative guess based on the reported basic range metric that we are told drastically undervalues the original SM-6's baseline capabilities. It could be as much as double the range under certain engagement profiles, we just don't know.
Being able to reach out and pummel ships with a high-speed ballistic missile from over 200 miles away would be an incredible capability to insert into the U.S. Navy's surface combatant force. Many potential enemy vessels are equipped to counter air-breathing threats, such as anti-ship cruise missiles and low-flying fighters—but not anti-ship ballistic missiles. Layering these weapons in with anti-ship cruise missiles, such as Block IV Tactical Tomahawks, Naval Strike Missiles (NSMs), and Long-Range Anti-Ship Missiles (LRASM), and even the ever more lethal Harpoon anti-ship missile for shorter-ranged engagements, during an attack on a hostile flotilla would give even the most well equipped naval force a run for their money defending against it. Even AEGIS class destroyers and cruisers, at least up until very recently, can't execute the ballistic missile defense and anti-air mission at the same time.
Hopefully, the SM-6 Block IB will also include its anti-air and localized ballistic missile defense functions as well, at least eventually. Maybe even the weapon's latent land attack capability will be more of a priority in the future considering the weapon's greater range. The line item in the budget seems to indicated that it will indeed be multi-role.
I think it's also time for the Pentagon to begin working on adapting the SM-6 for air-launch applications. It could become the long-range multi-purpose weapon of choice for the Navy and the Air Force. Not only could it take down enemy aircraft at hundreds of miles away—something the USAF is highly interested in out of necessity— but it could also blast ships and even incoming ballistic missiles at similarly long ranges with the help of being launched at altitude and high-speed.
The land attack potential is also key here. Not only could it hit fixed targets, but if the Advanced Anti-Radiation Guided Missile's (AARGM) multi-mode seeker was incorporated, it could go after key air defense components from very long ranges. An air-launched version could be carried by strategic bomber and medium-large fighter alike, from B-21 to the F/A-18E/F to the F-15. But having what amounts to a very long-range SEAD weapon forward deployed on ships would also be a big force multiplier for air components of an integrated combat force. And once again, it could use the geolocation data of threatening emitters sniffed up by aircraft like the F-35 for targeting at very long distances.
There is also the possibility that SM-6 could be adapted for submarine use. We have talked about this in the past, but we don't have any evidence that points to such a program existing beyond speculation.
Regardless, the SM-6 was already among the Navy's most promising and exciting weapons programs. Now that it is getting supersized to meet its maximum potential, its value will only become more undeniable and hopefully we will see it ported over onto multiple future naval platforms, and maybe even aerial ones, in the future.
Contact the author: Tyler@thedrive.com