The National Transportation Safety Board has launched an investigation into the near midair collision of a passenger jetliner and a cargo jumbo jet.

On May 21, 2010, at about 12:10 a.m. Alaska Daylight Savings Time, an Airbus A319, operating as US Airways flight 140, and a Boeing 747-400, operating as Cargolux Airlines International flight 658, came within an estimated 100 feet vertically and a .33 mile lateral separation as the B747 was departing Anchorage International Airport (ANC) and the A319 was executing go-around procedures at ANC.

The A319, with 138 passengers and crew aboard, was inbound from Phoenix (PHX) to runway 14 and the B747, with a crew of 2, was departing Anchorage en route to Chicago (ORD) on runway 25R. The incident occurred in night visual meteorological conditions with 10 miles of visibility.

According to the TCAS report from the A319 crew, that aircraft was approaching ANC when, because of the effects of tailwinds on the aircraft’s approach path, the crew initiated a missed approach and requested new instructions from air traffic control. The tower controller instructed the A319 to turn right heading 300 and report the departing B747 in sight. After the A319 crew reported the B747 in sight, the controller instructed the A319 to maintain visual separation from the B747, climb to 3000 feet, and turn right heading 320. The A319 crew refused the right turn because the turn would have put their flight in direct conflict with the B747. The A319 crew then received a resolution advisory to “monitor vertical speed” and the crew complied with the descent command. During the descent, the A319 crew lost sight of the B747. At about 1700 feet above ground level, the A319 crew received a “clear of conflict” aural command.

There were no reported injuries or damage to either aircraft.

NTSB investigator Dan Bartlett, an air traffic control specialist based in Washington, will be traveling to Anchorage to begin the investigation.

Source: NTSB