Northrop Grumman Corporation (NYSE: NOC) has won a contract to upgrade the inertial navigation systems (INS) for the Swedish navy’s submarines. Under the contract, awarded by Kockums AB, Northrop Grumman’s Sperry Marine unit will supply five MK 39 Mod 3C ring laser gyro systems for installation on two Gotland-class and two Södermanland-class submarines, with one set to be used for spares and training. The MK 39 Mod 3C systems will replace the existing spinning mass gyrocompasses currently fitted on the submarines. CA Clase AB, Sperry Marine’s sales and service representative in Sweden, was instrumental in securing the order. Kockums AB will perform the installations, which will be completed by 2011.