The X-31 aircraft returns from a test flight for the VECTOR (Vectoring Extremely Short Takeoff and Landing Control Tailless Operation Research) program. The X-31 uses thrust vectoring ? controlling the direction of its engine exhaust with paddle-like vanes ? to maintain control at high angles of attack and reduced speeds, well below the typical landing speed for an aircraft of its type. U.S. Marine Corps photo by Maj. Cody Allee.