The U.S. Navy and an unknown defense contractor are working on a new missile the service says will give its submarines a new, “disruptive offensive capability” to take on enemy ships. The previously unknown weapon, known as Sea Dragon, supposedly combines existing an U.S. Navy platform with an existing capability, is likely a new version of a versatile air defense missile capable of pinch hitting as an anti-ship missile.
The Washington Post over the weekend that Chinese hackers had compromised the computers of a Navy contractor and stolen 614 gigabytes of data. The stolen data pertained to the Navy’s Naval Undersea Warfare Center, which conducts research and development on submarine systems. , the stolen data includes, “signals and sensor data, submarine radio room information relating to cryptographic systems, and the Navy submarine development unit’s electronic warfare library.”
As if that weren’t bad enough, it also included data on the Navy’s new “Sea Dragon” weapon system. The Post withheld some key information about Sea Dragon at the request of the Navy, but did state that the weapon is a supersonic anti-ship missile for use by submarines. According to a statement by the Navy, the weapon was a “disruptive offensive capability” created by “integrating an existing weapon system with an existing Navy platform.” The weapon was to start underwater weapons testing later this year and be ready for service 2020.
What is Sea Dragon? Well, the Navy knows, as does a certain defense contractor. And it’s safe to say that China knows thanks to that 614 gigabytes of lost data. The fact that the missile is based upon “an existing weapon system” is a huge clue, as is the fact that it’s supersonic. All four of the Navy’s offensive missiles: the Harpoon anti-ship missile, Tomahawk land attack missile, the new Naval Strike Missile, and the Long Range Anti-Ship Missile are all subsonic missiles. We can count those weapons out.
What other existing Navy missiles fit the bill? Just one actually: the newish Standard Missile (SM) 6 air defense missile, or . The latest development of the Standard series of surface-to-air missiles, SM-6 is designed to be launched by U.S. Navy Arleigh Burke-class destroyers and Ticonderoga-class cruisers to defend the fleet from cruise missiles, manned aircraft, unmanned aircraft, and even short-range ballistic missiles. SM-6 has a range somewhere around 180 miles. The missile's only drawback is, originally designed to shoot down flying targets, it has a fairly small blast fragmentation warhead.
The SM-6 is indeed supersonic. In fact, it can fly at 3.5 times the speed of sound, or 2,685 miles an hour. The SM-6 also has the fun trick of taking targeting data from other Navy assets, including the E-2D Advanced Hawkeye airborne early warning and control aircraft and the F-35 Joint Strike Fighter. The system, known as , allows any of these airborne platforms to relay threat targeting data to SM-6 missiles.
Under a typical engagement, a E-2D Advanced Hawkeye flying ahead of the fleet could detect a swarm of incoming anti-ship cruise missiles. Because the cruise missiles fly low to the surface and radar is a line-of-sight sensor, the fleet’s radars would have difficulty detecting them until they were very close. But a E-2D flying high enough to see them at long range could pass on targeting data to an escorting destroyer, which could launch a volley of SM-6s to shoot down the cruise missiles. This vastly increases the ability of the fleet to defend itself, particularly as anti-ship missiles grow faster over time.
In 2016, then-Secretary of Defense Ashton Carter announced that SM-6 had an anti-ship capability. The Standard class of missiles has always had a secondary ability to attack ships—several were used in the late 1980s against Iranian warships during . In 2016, the Navy (yes, that Reuben James, the star of the Tom Clancy novel Red Storm Rising) with SM-6 missiles. The same E-2D in the scenario could instead detect a Chinese naval task force and the same destroyer launches the same missiles, only to destroy enemy ships.
The Navy’s Virginia-class submarines each have twelve vertical launch system (VLS) tubes in their nose, behind the sonar array, for Tomahawk land attack missiles. If the Navy can stick an undersea version of SM-6 in those silos, each Virginia sub could suddenly have a battery of 12 Mach 3.5 anti-ship missiles on call. Later versions of the Virginia class will include the Virginia Payload Module, which can accommodate 28 Tomahawk-sized missiles.
Now imagine a new scenario: the U.S. and China are at war. Somewhere in the Pacific, a Virginia-class submarine equipped with a Virginia Payload Module is ordered to a precise set of coordinates, at which point it is to launch all 28 SM-6 missiles on a particular heading. The submarine commander only knows what direction to shoot and that the target is a Chinese naval task force. Once the missiles are in the air, they receive targeting data from a carrier-based F-35 that has been using its stealth to shadow the Chinese warships.
The result is that the Chinese fleet is on the receiving end of 28 supersonic anti-ship missiles that suddenly show up on their radar screens 180 degrees from what they thought was the real threat: an American aircraft carrier. The Chinese fleet has four minutes to detect, track, and destroy all 28 missiles, and then there’s the matter of the huge aerial armada of American carrier-based aircraft that just showed up on their radar screens.
If SM-6 isn’t Sea Dragon, then the real Sea Dragon is likely something very much like it. There really is no other supersonic weapon in the U.S. Navy’s inventory that fits the requirements, and the abilities the missile brings to the table, particularly the ability to take targeting data from other assets, make it a very useful submarine-launched weapon. On the other hand, there might be considerable engineering challenges to make SM-6 fit in a submarine.
Or not. For now it’s just speculation, at least unless the Navy—or China—decides to release details on the real weapon.