The NTSB is investigating what it calls a "near midair collision" of the US Airways flight, which was inbound from Pheonix with 138 passengers aboard on May 21, with a Cargolux Airlines flight that was taking off on a nearby runway.
The NTSB is also looking at why an air traffic controller who was guiding the US Airways jet ordered the aircraft to make a turn that the crew refused to make because it judged the move would "have put their flight in direct conflict" with the Cargolux aircraft, according to the NTSB.
US Airways flight 140, an Airbus A319, came in from the north on Runway 14 about 12:10 a.m. when, because of the tail winds, it missed its approach on the north-south runway and began to circle around, the NTSB said.
As the jet passed Runway 25R, which runs east-west immediately to the south of Runway 14, it crossed paths with Cargolux Airlines flight 658, a Boeing 747 departing for Chicago with a crew of two.
The jets were separated by about a third of a mile laterally and 100 feet vertically -- a distance the Federal Aviation Administration has characterized as a "very severe loss of separation."
Visibility at the time was 10 miles, the NTSB said.
A preliminary investigation revealed the A319 requested new instructions from the air traffic control tower as it abandoned its landing attempt, according to the NTSB.
A controller told the crew to turn right and to maintain visual contact with the departing 747 as the A319 climbed to 3,000 feet, where it was again to turn right.
"The A319 crew refused the (second) right turn because the turn would have put their flight in direct conflict with the B747," the NTSB said in a statement.
The US Airways crew then complied with a command to descend and was clear of the conflict at an altitude of about 1,700 feet. Federal officials are investigating why the controller allegedly told the A319 to turn toward the 747.
Bridget Ann Serchak, spokeswoman for the NTSB, said an air traffic control specialist from Washington, D.C., will be sent up next week to investigate and wouldn't comment on possible causes until the facts were determined. The agency will release a preliminary report about the encounter in the next few weeks, she said.
Todd Lehmackher, a spokesman for Tempe, Ariz.-based US Airways, would say only that the company was cooperating with the NTSB as the investigation continues.
Repeated messages seeking comment at the Boca Raton, Fla., U.S. headquarters of Luxembourg-based Cargolux have not been returned.
John Parrott, manager of the Anchorage airport, said he had not heard of the incident Friday.
"I'm a little puzzled that it has somehow been reported as a midair but wasn't the talk of the airport," he said.
The incident is the latest in a spate of close calls around major airports that have safety officials concerned.
In April, a Southwest Airlines flight taking off from Houston's William P. Hobby Airport came within 125 feet of a news helicopter. The same month, a small private plane and a Southwest Boeing 737 came within 200 feet of each other when an air traffic controller at Bob Hope Airport in Burbank, Calif., misjudged the spacing between the planes.
In February, another Southwest jet descending toward the Burbank airport took evasive action to avoid colliding with a small plane.
NTSB Chairman Deborah Hersman in December criticized the FAA for failing to act on long-standing safety recommendations aimed at preventing such incidents.
Find James Halpin online at adn.com/contact/jhalpin or call him at 257-4589. The Associated Press contributed to this report.
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