The planes — an American Airlines Boeing 737 flying in from Miami with 97 people on board, and a United Airlines Airbus 320 flying in from Chicago with 68 people on board — landed safely within minutes of each other, just after midnight.  The controller — the lone person on duty in the tower — did not respond to pilot requests for landing assistance or to phone calls from controllers elsewhere in the region. According to internal records, the pilots also used a “shout line,” which pipes into a loudspeaker in the tower, to try and reach the controller.  The tower normally is staffed by one air-traffic controller from midnight to 6 a.m. The Associated Press, citing an aviation official who spoke on condition of anonymity because of the ongoing investigation, said the supervisor who was on duty simply fell asleep.  After learning of the incident, Transportation Secretary Ray LaHood ordered a second air-traffic controller to be on duty overnight at the airport. LaHood also instructed the FAA to examine staffing levels at other airports around the country.  “It is not acceptable to have just one controller in the tower managing air traffic in this critical airspace,” LaHood said.  Because the controller was not available, the planes’ pilots took matters into their own hands, broadcasting their progress as they approached and landed. They also were communicating with controllers at a separate facility in the region that does not handle landings.  Babbitt, in a statement issued Thursday, said he was “determined to get to the bottom of this situation for the safety of the traveling public.”  “Fortunately, at no point was either plane out of radar contact, and our back-up system kicked in to ensure the safe landing of both airplanes.”  The incident, which the National Transportation Safety Board also is reviewing, is the second time in as many years that the tower at National has gone silent, said a source familiar with tower operations who spoke on the condition of anonymity because he is not authorized to speak for the FAA.  The previous time, the lone controller on duty left his swipe-card pass key behind when he stepped outside the tower’s secure door and was unable to get back in, the source said. A controller at another facility mentioned that incident to a pilot as he was trying to land early Wednesday.  The nation’s air traffic control system has many layers, with a network of en-route controllers directing planes when they are at or near cruising altitude. The airspace beneath that is controlled by Terminal Radar Approach Control facilities known as TRACONs. Takeoffs and the final miles of runway approach are handled by controllers in airport towers.
A control tower supervisor at Reagan National Airport has been suspended while the Federal Aviation Administration investigates why he wasn’t available to aid two planes that landed at the airport early Wednesday.