Review after control tower lapse
US federal aviation officials are reviewing air traffic control staffing at airports around the country after two planes landed at Reagan National Airport in Washington without clearance from the airport tower because they were unable to raise anyone there.
An aviation official said an air traffic supervisor - the lone controller on duty at around midnight on Tuesday when the incident occurred - had fallen asleep.
Peter Knudson, a spokesman for the National Transportation Safety Board, said the pilots of the two planes were in contact with controllers at a regional Federal Aviation Administration facility about 40 miles away in Virginia.
After pilots were unable to raise the airport tower by radio, they asked controllers in Warrenton to call the tower, Mr Knudson said. Repeated calls from the regional facility to the tower went unanswered, he said.
Transportation Secretary Ray LaHood, responding to the incident, said in a statement that he has directed FAA to put two air traffic controllers on the midnight shift at Reagan National.
"It is not acceptable to have just one controller in the tower managing air traffic in this critical air space," Mr LaHood said.
Reagan National is located in Northern Virginia just across the Potomac River from Washington.
Mr LaHood also said he has directed FAA administrator Randy Babbitt to study tower staffing at other airports around the country.
Regional air traffic facilities handle aircraft within roughly a 50-mile radius of an airport, but landings, take-offs and planes within about three miles of an airport are handled by controllers in the airport tower.
The planes involved were American Airlines flight 1012, a Boeing 737 with 91 passengers and six crew members on board, and United Airlines flight 628T, an Airbus A320 with 63 passengers and five crew members.