Narrative:

Medium large transport vectored within coordinated climb area to avoid known traffic and given climb to 10000 ft. At 3500 ft medium large transport reported an RA and slowing climb, no traffic was observed. A few seconds later out of main bang a target with another sector's tag appeared indicating 4400 ft.

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Original NASA ASRS Text

Title: MLG CLBING IN DEP CTL AREA RECEIVED A TCASII RA ON AN UNKNOWN ACFT AT 900 FT ABOVE HIM. LTSS OCCURRED.

Narrative: MLG VECTORED WITHIN COORDINATED CLB AREA TO AVOID KNOWN TFC AND GIVEN CLB TO 10000 FT. AT 3500 FT MLG RPTED AN RA AND SLOWING CLB, NO TFC WAS OBSERVED. A FEW SECONDS LATER OUT OF MAIN BANG A TARGET WITH ANOTHER SECTOR'S TAG APPEARED INDICATING 4400 FT.

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.