Sikorsky continues to inch toward flying its X2 technology demonstrator coaxial compound helicopter for the first time at its R&D and test facility in Horseheads, N.Y. At press time, the X2 had made three separate “blades-on” ground runs, with a cumulative engine run time of 30 minutes. Data analyzed during the ground run includes the performance of the X2’s belly-mounted active vibration control system. James Kagdis, X2 program manager, said the ground runs will continue into this month before the aircraft is prepared for first flight. He declined to speculate on when the first flight would happen. The X2, which Sikorsky unveiled in 2005, incorporates a suite of advanced technologies, including active vibration control, contra-rotating rigid main rotor blades, hub drag reduction and an integrated auxiliary propulsion system.