Narrative:

We were cleared to 10000 ft by approach control. We were descending through 10000 ft when TCASII gave a TA. TCASII then came back with alert to stop rate of descent, which we did at 10500. A widebody transport was in a climbing turn right at us. TCASII showed he was within 700 ft. We had a visual with him the whole time and he climbed through our altitude slightly left of us without clearance. No report was made as far as we know by either aircraft or ATC.

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Original NASA ASRS Text

Title: WDB ARRIVING NRT HAS CLOSE ENCOUNTER WITH ANOTHER WDB DEPARTING NRT BTWN 10000-11000 FT.

Narrative: WE WERE CLRED TO 10000 FT BY APCH CTL. WE WERE DSNDING THROUGH 10000 FT WHEN TCASII GAVE A TA. TCASII THEN CAME BACK WITH ALERT TO STOP RATE OF DSCNT, WHICH WE DID AT 10500. A WDB WAS IN A CLBING TURN R AT US. TCASII SHOWED HE WAS WITHIN 700 FT. WE HAD A VISUAL WITH HIM THE WHOLE TIME AND HE CLBED THROUGH OUR ALT SLIGHTLY L OF US WITHOUT CLRNC. NO RPT WAS MADE AS FAR AS WE KNOW BY EITHER ACFT OR ATC.

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.