“Hypersonic” appears to become a major motto in the armament world. Beside missiles, we are about to also see shells fired at such speeds. The US Army has the lead, apparently.

M777A2 howitzer units will be the first to benefit from the hypersonic technology (Photo Credit: U.S. Marine Corps photo by Cpl. Levi Schultz)

Let’s first recall what hypersonic means: a speed above Mach 5 (7,250 km/h, 4,506 mph), a speed where dissociation of air begins to become significant and high heat loads exist. The US Army is planning to demonstrate artillery technology capable of firing hypersonic projectiles in a short or medium term.

Speaking to Defense News on March 19, Brigadier General Stephen Maranian, team leader for the Long-Range Precision Fires (LRPF) modernization team, said the U.S. Army is planning to extend the cannon on M777 Howitzer units to "be able to achieve the velocity out of the tube that hypersonic speeds would require."

Etending the cannon's tube from a 39-caliber to a 58-caliber will take place after the service finishes testing the XM113, a projectile "filled with insensitive high explosive munition and a supplementary charge," according to an Army fact-sheet on the rocket-assisted artillery round. The projectile is currently under development at Yuma Proving Ground, Arizona, and could be delivered to US Army artillery teams in two and a half years, Maranian told Defense News.

The XM113 round will increase the range of howitzers by about 33 percent, from about 30 km (18.6 miles) to 40 km (24.8 miles). Each round will be compatible with US Army precision guidance kits that turn artillery shells into smart weapons.