China develops new stealth cruise missile

China is reportedly developing a new stealth cruise missile sized to fit inside the internal weapons bays of its J-20 and J-35 stealth fighters, according to technical design documents released in Weibo.

The missile’s design specifications set its length at under 4 meters and diameter under 0.85 meters — dimensions that are almost certainly driven by the internal bay dimensions of China’s fifth-generation fighters rather than any other constraint. The J-20, China’s primary stealth air superiority platform, and the J-35, its newer carrier-capable stealth fighter, both feature internal weapons bays designed to preserve their low-observable profiles by keeping munitions concealed from radar. A missile that fits inside those bays can be carried to its launch point without compromising the aircraft’s stealth signature, then released to fly the remaining distance to its target independently.

The aerodynamic configuration visible in the design documents shows a conventional fixed-wing layout with a blended body, parallel wing design, V-tail configuration, and a serrated exhaust nozzle at the rear. The serrated nozzle is a stealth feature borrowed directly from low-observable aircraft design — the jagged edge breaks up radar reflections from the exhaust cavity in the same way that serrated edges on stealth aircraft panel joints reduce their radar cross-section. The V-tail serves a dual purpose, providing both flight control surfaces and physical shielding of the engine exhaust from infrared sensors looking up at the missile from below. These are not incidental design choices. Every visible feature of the aerodynamic layout is oriented toward reducing the missile’s detectability across multiple sensor spectrums simultaneously.

The infrared suppression system is where the design becomes particularly sophisticated. Four cooling nozzles are positioned around the engine exhaust — one at each corner of the nozzle opening — injecting cold air into the hot exhaust plume to reduce its infrared signature.

The engine nozzle and the cold air injection ports are both recessed behind an outer shroud, so that the hottest components of the exhaust system are physically hidden from infrared sensors viewing the missile from most angles. A rock wool thermal insulation layer surrounds the engine to reduce heat transfer to the missile body.

The V-tail fins provide additional shielding of the exhaust when viewed from behind. Taken together, this layered approach to infrared suppression addresses the thermal signature problem from multiple directions simultaneously rather than relying on any single technique, and the design documents indicate it is expected to significantly improve the missile’s infrared stealth performance.

The performance parameters confirmed in the design material describe a subsonic weapon: cruise speed of 0.71 Mach, maximum level flight speed of 0.75 Mach, and a range of 1,330 kilometers. Subsonic cruise speed is a deliberate trade-off in stealth missile design — higher speeds generate more heat and more acoustic signature, while subsonic flight allows the stealth shaping and infrared suppression features to do their job more effectively. At 1,330 kilometers range, launched from a J-20 or J-35 operating well outside the defensive perimeter of a target carrier strike group, the missile reaches a strike radius that fundamentally complicates the defensive geometry for any surface fleet in the Western Pacific.

The contrast with the U.S. AGM-158C Long Range Anti-Ship Missile is explicit in the source material. The LRASM, America’s primary stealth anti-ship missile, is too long to fit inside the internal weapons bays of either the F-35 or the F-22, requiring external carriage that exposes the launching aircraft’s radar cross-section during the approach to its launch point. The Chinese missile’s sub-4-meter length specifically solves the problem that LRASM creates for American fifth-generation fighters — it allows the entire strike package, aircraft and weapon, to remain stealthy from launch platform to target. That asymmetry has direct implications for how the two countries’ stealth air fleets can be employed in a high-end naval engagement.

A stealth cruise missile that fits inside a stealth fighter’s internal bay, flies 1,330 kilometers at subsonic speed, suppresses its own infrared signature through active cooling, and can be carried two at a time by each of China’s 200-plus J-20 aircraft describes a weapon system designed with a specific threat in mind. U.S. carrier strike groups operating in the Western Pacific have long been the anchor of American power projection in the region. A weapon that can be launched from inside a stealth aircraft’s bay, beyond the range of most carrier-based defensive systems, while minimizing the signatures that would allow it to be detected and intercepted, is designed to reach those carriers. Whether it can do so in practice depends on how the weapon performs when it is actually built and tested.