THE Pentagon today announced the possible sale of three Aegis naval weapons systems to Australia, saying it would increase the ability of the US and Australian navies to operate together. The Defence Security and Co-operation Agency (DSCA) estimated the value of the sale could be as high as $US350 million ($460 million). Aegis systems are centred on a sophisticated computerised command system that can cue air defence missiles to attack enemy missiles and aircraft detected by targeting radar. Using its AN/SPY-1 phased array radar, it can track over 100 targets simultaneously.Noting Australia's strategic location, the DSCA said helping the Royal Australian Navy (RAN) modernise its fleet of surface warships was vital to US interests. "The procurement also aids in maintaining the US Navy (USN) production base and will improve interoperability between RAN and USN forces," it said. "This proposed sale is consistent with those objectives, and facilitates burden sharing with our allies." Lockheed-Martin Maritime System and Sensors, Raytheon, General Dynamics were the principal contractors, DSCA said.