A new long-range air-to-air missile for the Boeing F/A-18E/F Super Hornet will pose a challenge for Chinese aircraft and unmanned air vehicles (UAVs) attempting to target US aircraft carrier battle groups.
Dummy rounds of the missile, designated the AIM-174B, were spotted on the wings of operational US Navy (USN) Super Hornets at the recent Rim of the Pacific, or RIMPAC, exercises in Hawaii.
The weapon is based on the USN’s primary ship-launched interceptor, the Raytheon SM-6. In a brief email to FlightGlobal the USN confirmed that the weapon is in service.
“The SM-6 Air Launched Configuration (ALC) was developed as part of the SM-6 family of missiles and is operationally deployed in the navy today,” it says.
The USN has not released official images, but shots of the weapon appeared on social media, including posts on Reddit apparently shot in the hangar of the USS Carl Vinson.
As it is based on a ship-launched missile, the AIM-174B is big, likely weighing in around five times more than the US military’s premier air-to-air missile, the 162kg (356lb) Raytheon AIM-120D Advanced Medium Range Air-To-Air Missile (AMRAAM).
Given the AIM-174B’s size, it is unlikely that that the weapon can be carried on the Super Hornet’s two fuselage missile mounts, which are equipped with LAU-116 launchers for the AMRAAM.
The Super Hornet has three pylons under each wing. The Carl Vinson hangar images show a dummy round of the AIM-174B carried on the jet’s middle pylon. An airborne shot of an F/A-18F appears to show the weapon on the inner pylon. Given that both the inner and middle pylons can accommodate larger missiles and bombs, it is probable that the Super Hornet can carry four AIM-174Bs.
The missile’s large size certainly brings range. Published ranges for the ship-launched SM-6 run from 130nm to 240nm (241km to 444km). Irrespective of the weapon’s exact performance specifications, the air launch of such a large missile from a fast-moving fighter at high altitude all but guarantees exceptional range.
Given that the Super Hornet’s combat radius can be extended by air-to-air refuelling – particularly when the Boeing MQ-25 Stingray refueller enters service – the AIM-174B will allow the fighter to prosecute targets at vast distances from the aircraft carrier. This reach is a critical capability given that Chinese doctrine calls for striking USN aircraft carrier battle groups with both long-range cruise missiles and anti-ship ballistic missiles.
The AIM-174B is likely aimed at the nodes in Chinese kill chains that facilitate such strikes.
It is known that the SM-6 can receive real-time targeting information from assets other than the launch platform. While the Super Hornet’s Raytheon APG-79 is an effective active electronically scanned array radar, the missile can also take mid-course updates from other assets, such as airborne early warning and control aircraft, UAVs, and potentially Lockheed Martin F-35s operating closer to enemy assets.
The SM-6 has its own seeker – derived from that used in the AMRAAM – for terminal guidance into the target.
Justin Bronk, a senior research fellow at the Royal United Service Institute, offers this perspective on the new missile: “The AIM-174B should enable the USN’s carrier air wings to threaten Chinese big-wing [intelligence, surveillance, target acquisition and reconnaissance] assets and bombers from sufficiently long ranges to meaningfully increase the survivability of carrier battle groups by increasing missile salvo warning times and disrupting some kill chain options.”
If China’s regular aerial forays against neighbouring Taiwan are anything to go by, key platforms for setting up kill chains include the Shaanxi KJ-500 airborne early warning and control (AEW&C) aircraft, and UAVs such as the Harbin BZK-005 and Tengden TB-001.
When China’s aircraft carrier capabilities reach a further level of maturity, particularly the commissioning of CNS Fujian, the country’s first super carrier, the new KJ-600 will also be instrumental in supporting Chinese kill chains.
As for Chinese long-range strike assets, the Pentagon has taken notice of later versions of the Xian H-6, a thoroughly modernised bomber originally based on the Tupolev Tu-16.
The H-6K/J features three hardpoints under each wing. The H-6J is especially focused on naval warfare, capable of carrying six YJ-12 supersonic anti-ship cruise missiles. This allows it to strike ships out to the “Second Island Chain”, which extends from Japan through Guam to the South Pacific, in support of the older H-6G, which itself can carry four YJ-12s.
The Global Times, a Chinese propaganda outlet, recently reported that an H-6K was spotted carrying four YJ-21 hypersonic anti-ship ballistic missiles.
In a conflict, Super Hornets using the AIM-174B would be able to degrade the resiliency of Chinese kill chains by either destroying AEW&C aircraft and UAVs, or at least forcing them to operate at greater distances from targets. They may also be able to hit launch platforms such as the H-6 before they have the chance to launch their missiles.
What is not clear is if the weapon will be deployed on other aircraft, such as the F-35. Two variants of F-35 operate from USN vessels. The USN’s F-35C is optimised to operate from US carriers equipped with catapults and arresting gear, while the US Marine Corps operates the short take-off vertical landing F-35B from amphibious assault ships.
While the F-35 could accommodate the AIM-174B under its wings, it would not be able to carry it internally, which obviates the fighter’s low observable characteristics.
Another tantalising possibility is the use of the weapon aboard US Air Force (USAF) Boeing F-15s, which are widely deployed in Japan. There is no evidence that the AIM-174B is intended for USAF service, but the F-15 is renowned for its payload carriage.
If nothing else, the AIM-174B serves as an effective stopgap until the arrival of the developmental AIM-260 Joint Advanced Tactical Missile, the planned long-range replacement for the venerable AMRAAM. Original plans had called for this weapon to be deployed in 2022, but there has been little public information about the programme in recent years.
With the AIM-174B the USN has sent an important message to China, whose anti-access/area denial strategy is based on extended kill chains incorporating long-range fires. It is a reminder that China does not have a monopoly on defence innovation, and the USN is far from standing still.
