WASHINGTON (AP) â€” ``Stop!'' shouted the frightened air traffic controller as a giant Boeing 747 that had just landed headed into the path of another jumbo jet preparing to take off from the Chicago runway.
Tragedy was avoided as the second plane climbed quickly, but the incident was closely studied Tuesday as the National Transportation Safety Board issued recommendations for avoiding such close calls.
Luck was with the passengers and crew aboard the two planes, observed NTSB Chairman Jim Hall, ``but relying on luck doesn't make good public policy.''
Hall noted that more than 320 runway close calls were reported nationwide last year, a number that has been rising over the years as airport traffic increases.
The Chicago case and another in Providence, R.I., in which planes on the ground become lost in the fog were studied before the board issued its recommendations.
Those now go to the Federal Aviation Administration, which has already launched its own effort to reduce such incidents and plans a national runway safety summit June 26-28.
In the Providence case last Dec. 6, United Airlines Flight 1448 became lost in the fog and turned down a wrong taxiway leading toward a runway where a FedEx plane was taking off.
As it became clear from radio conversations that the United flight wasn't where it ought to be, the air traffic controller, also blinded by fog, ordered it to halt. She then cleared a US Airways flight to take off, but that pilot refused to go until he was sure where everybody was.
Eventually, after all movement at the airport was halted, the United pilot was able to read runway signs to determine where he was and could then taxi to a safe location so operations could resume.
The Chicago case occurred April 1, 1999, when an Air China International 747 cargo plane with a crew of eight aboard landed and turned onto the wrong taxiway. It then began to cross a runway just as a Korean Air 747 with 357 passengers and 22 crew members started to take off.
The unexpected appearance of the Chinese jet on the runway prompted the controller to shout ``Stop!'' just seconds before the planes would have collided. It was too late for that, but the Korean pilot was able to lift off early and veer sharply to the left, avoiding disaster.
In their recommendations, board members criticized the FAA for slow progress in developing technology to avoid runway incidents. They urged the agency to speed up that effort and to:
â€”Require that a pilot get a specific clearance before crossing each runway. Currently that clearance is implied when a pilot is told to proceed to the takeoff point, or a multiple clearance may be given to cross several runways.
â€”Prohibit planes waiting to take off from idling on an active runway at night or in conditions where they might not be visible to incoming planes.
â€”Adopt the English language phraseology recommended for ground operations by the International Civil Aviation Organization, and direct controllers to speak clearly and slowly, especially when dealing with foreign planes.
The United States already follows most ICAO terminology but there are some differences that may confuse pilots from other countries. For example, if an American controller wants a plane to go to a runway and stop until given further directions, the pilot will be told to ``taxi and hold short'' or ``position and hold short.'' The ICAO direction would be ``line up and wait.''
Downward looking radar is in service at some airports and that can help controllers monitor planes' movements. Improved versions are under development, said John Mayrhofer, director of the FAA's runway safety program.
A system called Airport Movement Area Safety System, to begin service later this year, sounds an alert when planes seem to be heading for a collision. It is expected to be in the nation's 34 busiest airports by 2002, he said.
But NTSB officials questioned whether AMASS will give enough warning, and urged that other systems also be studied.
Mayrhofer said an improved system is under development that uses ground sensors and Global Positioning System readings as well as radar.
On the Net:
National Transportation Safety Board: http://www.ntsb.gov
Federal Aviation Administration: http://www.faa.gov