Raytheon has successfully fired its new Excalibur N5 projectile during a recent live guided flight test at Yuma Proving Ground, Ariz.  It was fired from a 5-inch naval gun during testing (shown, top photo). Excalibur N5 (bottom photo) is a 5-inch/127 mm naval variant of the projectile used by the U.S. Army, the U.S. Marine Corps and several international armies--Sweden, Canada, Australia and the Netherlands have selected Excalibur for their military services. The projectile uses a built-in ruggedized GPS receiver and satellite signals to help guide itself to its intended target. It is expected to more than triple the maximum effective range of conventional naval gun munitions and deliver the same accuracy of the Excalibur Ib, which is in production today.


Excalibur’s  advantages include a major reduction in the time, cost and logistical burden associated with using conventional artillery munitions. It is being developed to support several critical naval mission areas including Naval Surface Fire Support, Anti-Surface Warfare (ASuW) and countering Fast Attack Craft (FAC). It is said to have what is known as “a radial miss distance” of less than two meters from the target, greatly reducing the possibility of collateral damage; the munition has been employed within 75 meters of supported troops. Nearly 770 Excalibur rounds have been fired in combat, according to its manufacturer.


The main challenge to GPS guided munitions comes from GPS jammers and spoofing equipment. This is not a theoretical threat: in 2011, North Korea blocked South Korean GPS signals, reportedly using Russian-made jamming equipment capable of disrupting the guided weapons. Also in 2011 Iran downed and captured an RQ-170 Sentinel drone, claiming it had spoofed GPS data and redirected the drone to land inside Iranian borders. In response to this counter-measure Raytheon is developing a laser-guided version of the projectile, to be called the Excalibur S. This variant incorporates a digital semi-active laser seeker, allowing it to hit moving targets and engage and strike targets without GPS-based location information. In this way it reduces the risk associated with GPS jamming.


Testing is continuing at Raytheon.