Japan's plan to build hypersonic weapons is a direct challenge to the Chinese navy, experts say. Credit: Sino Defence.

It travels toward its target faster than five times the speed of sound, making course corrections nearly impossible to track, and carries a “Sea Buster” tandem charge warhead designed to attack surface warships and penetrate carrier decks.

According to Jane’s, it is composed of a main warhead, which carries armour-piercing high-explosive shells and a nose fuze, and a precursor warhead that uses shaped charges.

Difficult to stop and capable of breaking through enemy air defense systems, it is a weapon that could cause havoc for the Chinese navy in the South China Sea, and the Japanese military plan to put it in use by 2026 — a “game changer,” as it’s described by ATLA, the agency developing the missile.

According to David Axe of The National Interest, Japan’s defense ministry is developing what it calls an anti-ship “hypervelocity gliding projectile,” or HVGP, for deployment on island bases.

The Japanese weapon’s designation is something of a misnomer. In US parlance, a guided missile traveling faster than five times the speed of sound is a “hypersonic” weapon. The Americans reserve the “hypervelocity” designation for fast, unguided cannon shells.

In any event, Tokyo wants the new HVGP to help it defeat Chinese forces, The National Interest reported.

The 2026 model is for “targeting a potential enemy invading Japan’s remote islands,” The Mainichi newspaper reported. “In the second stage, an upgraded type will be developed for possible installation in fiscal 2028 or later, featuring claw-shaped payloads, enhanced speeds and firing ranges and more complex trajectories.”

Another enhancement after 2026 could add a “payload that is capable of penetrating the deck of aircraft carriers,” Mainichi explained.

The HVGP is a boost-glide system. It launches atop a rocket, then separates from the booster and, guided by GPS, glides at hypersonic speed via a Dual-Mode Scramjet engine (DMS) toward its target, The National Interest reported.

Dual mode, in the sense: the rocket booster only needs to accelerate the missile to supersonic speed, and from there, the ramjet engine accelerates the missile to hypersonic speed, which then activates the scramjet engine to cruise.

It’s unclear what special “payload” the Japanese are considering specifically for targeting Chinese aircraft carriers. According to sources at Jane’s, it could be the “Sea Buster” warhead, a weapon specifically developed to target enemy surface vessels, most likely larger warships, or be used for “area suppression.”

However, the kinetic energy of a hypersonic missile alone should be sufficient to disable or destroy most targets, land or sea, The National Interest reported.

One such warhead — a Multiple Explosively Formed Penetrator (MEFP) — will be able to release dozens of hypervelocity metal fragments capable of striking several targets, Jane’s reported, citing documents.

Warhead guidance is achieved via either radio-frequency imaging converted from doppler shift data — which the government agency said will be able to identify naval targets in all weather conditions — or an infrared seeker capable to discriminating specific targets, Defense News reported.

Easier said than done, however, and this is the hard part.

According to naval experts interviewed by Forbes magazine, first, they would have to find the target; then they would have to fix its location; then they would have to establish a continuous track of its movements; then they would have to actually target it with specific weapons; then they would have to penetrate multi-layered defenses to reach the target; and finally they would need to assess whether the resulting damage was sufficient to disable the target.

Japan’s hypersonic missile is a direct response to China’s years-long campaign of maritime land-grabs and fortress-construction in the South and East China Seas. Credit: ATLA.

Because each step must be accomplished sequentially, if any “link” in the kill chain fails the whole process breaks down, Forbes reported.

After decades of development, hypersonic weapons finally are beginning to enter front-line service. The Russian defense ministry in late 2019 claimed it had deployed the Avangard surface-to-surface hypersonic missile, possibly making Russia one of the first countries to field an operational hypersonic weapon, The National Interest reported.

Chinese media claimed China is testing two hypersonic surface-to-surface missiles. The DF-17 made its first public appearance as part of the October 2019 celebrations commemorating the 70th anniversary of the founding of the People’s Republic of China. The second missile, the Xingkong-2, reportedly differs in detail.

The US Air Force successfully conducted a flight test of its own hypersonic Air-Launched Rapid-Response Weapon back in June 2019. The ALRRW could enter service as early as 2023. The B-1 and B-52 bombers both are possible launch platforms for the new weapon, The National Interest reported.

The US Navy and US Army meanwhile are working together on a booster for a Mach-5-plus missile plus a common glide body for a hypersonic weapon’s second stage. The Navy has identified the new Block V version of its Virginia-class attack submarine as the initial launch platform for the fast missile.

Japan’s hypersonic missile is a direct response to China’s years-long campaign of maritime land-grabs and fortress-construction in the South and East China Seas.

“Chinese government vessels have been frequently spotted navigating in contiguous zones near the Senkaku Islands and intruding into Japanese territorial waters,” Mainichi noted.

The Japanese military’s existing land-based weapons lack the range to strike, from Japanese soil, the outermost Chinese outposts.

“The introduction of longer-range gliding missiles to protect the Nansei Islands would make it possible for Japan to respond to China’s activities without deploying the Maritime Self-Defense Force’s vessels and aircraft,” Mainichi reported.

The hypersonic guided missile is ground-launched, Naval News reported, but under current plans, the Japan Air Self-Defense Force (JASDF) will deploy three different types of modern anti-ship missiles: