HUNT VALLEY, Md., 6 Nov. 2011. Officials of the U.S. Naval Air Warfare Center Aircraft Division UAS Test Directorate at Patuxent River Naval Air Station, Md., has established and demonstrated a dedicated Shadow tactical unmanned aerial vehicle (UAV) for test and evaluation -- primarily for U.S. Marine Corps users, Navy officials announced. The Shadow UAV is from AAI Unmanned Aircraft Systems (UAS) in Hunt Valley, Md. Shadow is replacing the old Pioneer UAVs in the Navy and Marine Corp inventory. The last Pioneer UAV was retired from service in 2007.