Poor Rules Almost Led to Mid-Air Collisions, NTSB SaysAlan Levin
A series of near mid-air collisions at commercial airports in recent years exposed inadequate air-traffic control procedures that create excessive risk for planes aborting a landing, accident investigators said today.
There is “no safety justification” for current rules that in at least five cases since 2006, including four last year, put planes on collision courses near an airport, the U.S. National Transportation Safety Board said today.
The current rule “facilitates hazardous conflicts and introduces unnecessary collision risk,” and may leave pilots on their own to avoid hitting another plane, the NTSB said in a letter to the Federal Aviation Administration calling for a change in procedures.
The near collisions occurred when the plane that aborted its landing began climbing just as another aircraft lifted off from or prepared to land at an adjacent runway, putting the two planes flying toward each other, the NTSB said.
The incidents occurred at Las Vegas McCarran International, New York’s John F. Kennedy International and Charlotte-Douglas International, according to the safety board.
The agency, which investigates aviation accidents and incidents, has no regulatory authority and can only make recommendations for safety improvements.
“The NTSB has determined that existing FAA separation standards and operating procedures are inadequate and need to be revised to ensure the safe separation between aircraft near the airport environment,” the agency said in an e-mail.
Planes are allowed to land and take off simultaneously on runways with converging paths if the runways don’t touch. Normally, planes on the two runways stay apart as the landing plane slows and turns off the runway.
A safety issue arises in the unusual case when pilots on a plane that is about to land decide to abort the landing in what is known as a “go around.” Pilots are encouraged to go around if they aren’t properly set up to touch down or another plane is on the runway.
At some airports, such as at Las Vegas and New York’s Kennedy, a pilot who aborts a landing and begins climbing may head directly for the path of other departing or arriving flights, according to the safety board.
If planes are taking off on runways with converging paths, FAA regulations require controllers to wait for one plane to clear the airspace before allowing another one to take off, to keep them separated. The current rules contain no such requirement in the event of an aborted takeoff, according to NTSB.
“Instead, separation was established by resorting to impromptu evasive maneuvers by pilots during critical phases of flight,” the NTSB said.
A Spirit Airlines Inc. plane, an Airbus SAS A319, and a Cessna Aircraft Co. Citation 510 corporate jet came within one-quarter mile (0.37 kilometers) of colliding just above Las Vegas’ airport on July 30, 2012, according to the NTSB.
As the Spirit plane climbed, the Citation’s pilots had to turn left to go behind it, according to the board’s letter.
On the same day at Kennedy, an AMR Corp. American Airlines Inc. Boeing Co. 757 came within 0.35 miles (0.56 kilometers) of a Pinnacle Airlines Corp. Bombardier Inc. CRJ 200 regional jet, the NTSB said in the letter.
The American plane had aborted its landing and climbed toward the Pinnacle aircraft. The American pilot refused a directive from an air-traffic controller to climb to 2,000 feet altitude.
“Negative, we are trying not to hit this aircraft off our right,” the pilot replied, according to the safety board.