SAN DIEGO -- The Federal Aviation Administration blamed an air traffic controller at Lindbergh Field for clearing a Southwest Airlines plane for takeoff last week while another jet was stuck on the runway, it was reported.

FAA spokesman Ian Gregor said the controller erred by clearing Southwest Flight 1626 for takeoff while a Hawker Siddeley corporate jet remained on the runway due to a mechanical problem.

The controller had anticipated the Hawker would exit the 9,400-foot-long runway in time and therefore cleared the Southwest flight for takeoff during the Jan. 16 incident, the report said.

Gregor said at the time the Southwest plane lifted off, the two aircraft were just 2,500 feet apart, the San Diego Union-Tribune reported.

''There was no collision hazard because Southwest took off a half-mile from where the (other plane) was,'' Gregor was quoted as saying.

Gregor said earlier the FAA had looked into the incident and did not consider it a safety breach.

The National Air Traffic Controllers Association said it believes the FAA initially tried to cover it up.

Melvin Davis, the San Diego chapter president of the union, said the incursion should have raised a red flag with the FAA about the state of the nation's air traffic control system in view of continuing staffing issues.

Davis said the controller involved had been working six days a week because of staffing strains at Lindbergh, the Union-Tribune said.

Rep. Bob Filner, D-San Diego, has requested a congressional investigation into the incident.

The last recorded runway incursion at Lindbergh took place in late 2003.