Narrative:

We were departing on runway 16 departure, cleared to 7000' by departure control. We noticed lights at 12 O'clock and mentioned we better keep our eyes on them. Visibility was restr by haze and intermittent clouds and darkness, making it very difficult if not impossible to determine altitude of oncoming aircraft. First officer was flying aircraft and was just ready to take evasive action when the other aircraft veered to the left just as we reached 6000'. He passed off to our right at a distance estimated to be some what less than 1/2 mi distance. At the same time, the controller told us to maintain 5000', but by that time it was too late to have any effect on the situation. We asked for the identity of the other aircraft and were informed that it was a widebody transport flight.

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Original NASA ASRS Text

Title: FLT CREW OF WDB DEPARTING NARITA AND AT 6000' MSL OBSERVED A WDB TAKE EVASIVE ACTION TO AVOID, AT SAME ALT. NARITA CTL ADVISED REPORTER THEY KNEW WHO THE FLT WAS.

Narrative: WE WERE DEPARTING ON RWY 16 DEP, CLRED TO 7000' BY DEP CTL. WE NOTICED LIGHTS AT 12 O'CLOCK AND MENTIONED WE BETTER KEEP OUR EYES ON THEM. VISIBILITY WAS RESTR BY HAZE AND INTERMITTENT CLOUDS AND DARKNESS, MAKING IT VERY DIFFICULT IF NOT IMPOSSIBLE TO DETERMINE ALT OF ONCOMING ACFT. F/O WAS FLYING ACFT AND WAS JUST READY TO TAKE EVASIVE ACTION WHEN THE OTHER ACFT VEERED TO THE L JUST AS WE REACHED 6000'. HE PASSED OFF TO OUR R AT A DISTANCE ESTIMATED TO BE SOME WHAT LESS THAN 1/2 MI DISTANCE. AT THE SAME TIME, THE CTLR TOLD US TO MAINTAIN 5000', BUT BY THAT TIME IT WAS TOO LATE TO HAVE ANY EFFECT ON THE SITUATION. WE ASKED FOR THE IDENTITY OF THE OTHER ACFT AND WERE INFORMED THAT IT WAS A WDB FLT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.