As of June 19, eLoran is on the air in the United States. The low-frequency signal emanates from a former U.S. Coast Guard Loran Unit in Wildwood, N.J., which sports a 625-foot signal mast that has been out of action for five years. The signal is receivable at distances of up to 1,000 miles. The eLoran navigation and communications signal is difficult to disrupt; further, it could be an important part of enabling UAVs to fly safely in our airspace.