Marking a milestone, Northrop Grumman Corp. recently shipped the 500th AN/WSN-7 ring laser gyroscope inertial navigation system (INS) to the U.S. Navy in support of naval operations across the globe. “Installed across the U.S. Navy Fleet, Northrop Grumman continues to support U.S. and NATO surface and submarine naval platforms around the world,” said Todd Leavitt, vice-president, naval and oceanic systems for Northrop Grumman.
Shipment of the accurate and dependable AN/WSN-7 ring laser gyroscope INS (see the figure) extends the production of gyroscope systems that began in 1911 with the installation of the first gyroscope installed on the USS Utah, the second and final member of the dreadnought class of battleships. The AN/WSN-7 is the U.S. Navy Program of Record for INS for all surface combatants equipped with AEGIS weapons systems, including Ticonderoga-class missile cruisers and Arleigh-Burke-class destroyers, as well as all Nimitz-class aircraft carriers.
Rather than a mechanically rotating gyroscope, the AN/WSN-7 INS employs a ring laser with two independent counter-propagating resonant modes. Differences in phase are used to detect rotation and plot paths. The navigational system is specified for 1-nm positional accuracy across 24 hours of use. For Sea Wolf and Virginia-class submarines, the AN/WSN-7A INS provides the same level of performance as the AN/WSN-7, in a modified form factor for submarine use.