Excalibur S artillery shell can change course in flight

Raytheon's dual-guidance system can switch from GPS to laser guidance to hit moving targets, reduce collateral damage.

Using a combination of Global Positioning System satellites and laser-guidance, soldiers calling in precision artillery strikes may soon be able to change their targets as the shells travel through the air. 

Raytheon successfully conducted the first live fire test of the company-funded Excalibur S artillery shell on June 15, according to the company. The dual-mode GPS- and laser-guided shell was initially aimed with a GPS target location and then terminally guided onto a different, offset target. 

The Excalibur S is an improvement of Raytheon’s Excalibur 1b, which itself was an upgraded version of the original Excalibur projectile that reduced costs and increased reliability. The GPS-guided 155mm howitzer shells are capable of achieving a radial miss distance of less than two meters from the intended target.

The round was the result of collaboration between Raytheon, which provided the guidance system, and BAE Systems Bofors, which provided the actual round. Using folding glide fins, the round is able to glide from the top of a ballistic arc and maneuver toward targets, giving it a range of about 25 to 35 miles.

Excalibur was accurate enough that tactics, techniques and procedures (TTPs) regarding the shells were changed, according to DOD Buzz. Artillerymen were initially required to use two rounds for each target, but that was reduced to a single shell per target after the services realized the system’s accuracy.

The new Excalibur S adds a laser spot tracker into the Excalibur 1b -- the test showed that the tracker was able to survive being fired from a 155mm howitzer and was capable of operating after switching from GPS guidance.

The new capability will allow ground troops to change a shell’s impact point to avoid casualties and collateral damage, hit targets that have repositioned after the initial salvo, or attack moving targets.

"The significance of this new capability cannot be understated," said Michelle Lohmeier, vice president of Raytheon Missile Systems' Land Warfare Systems product line. "A laser-guided variant of Excalibur gives the warfighter a precision weapon that accommodates target location errors, allows continued target attack when GPS is degraded or denied, and hit targets on the move at extended ranges."  

In addition to the Excalibur S, Raytheon is developing the Excalibur N5, which will incorporate the same the same capabilities into a shell compatible with 127mm/5 inch naval guns that are used by Navy destroyers and cruisers. The Navy recently issued a Request for Information to look at the feasibility of long-range, guided shells for its 5 inch guns. Raytheon expects to live-fire the Excalibur N5 later this year.