Boeing said it conducted a successful first mission system test flight of an Airborne Warning and Control System (AWACS) aircraft upgraded under the Block 40/45 program, the largest enhancement in the history of the U.S. Air Force E-3 AWACS fleet. Boeing said during the seven-hour flight April 5 from Boeing Field in Seattle, the crew conducted functional tests of the aircraft's enhanced navigation, communications, radar and mission computing subsystems. In future test flights, the company said it will further calibrate the upgrades and measure their performance. The mission system flight test program is scheduled for 62 flights over the next several months. Under the Block 40/45 program, Boeing outfitted the Test System 3 AWACS aircraft with new mission computing hardware and software, upgraded radar equipment, and navigation and communications systems. These enhancements are designed to increase the aircraft's capability through improved automation, human computer interface and reliability as well as lowered lifecycle costs. Based on a Boeing 707-320B airframe, the E-3 AWACS provides wide-area surveillance, command-and-control and communications functions for all airborne assets in any theater of operation.