Narrative:

Bos approach vectored us, air carrier 1ABC, out of holding and descended us to 11000 ft. Another air carrier, abc, was also being vectored at 11000 ft. TCASII alerted us of the conflict and we climbed immediately. The controller queried us on our altitude and instructed us to climb back to 13000 ft. The problem arose because of controller error. Contributing factors include: similar call signs, WX and holding pattern. Conflict was discovered via TCASII (great tool). We were aware of the other air carrier, abc, and very conscious of controller's instructions. Holdings and altitudes were read back clearly and double-pointing at the new mode control panel altitude was accomplished.

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Original NASA ASRS Text

Title: A B757 FO RPTED A TFC CONFLICT DURING DSCNT FROM A HOLD IN THE VICINITY OF PVD.

Narrative: BOS APCH VECTORED US, ACR 1ABC, OUT OF HOLDING AND DSNDED US TO 11000 FT. ANOTHER ACR, ABC, WAS ALSO BEING VECTORED AT 11000 FT. TCASII ALERTED US OF THE CONFLICT AND WE CLBED IMMEDIATELY. THE CTLR QUERIED US ON OUR ALT AND INSTRUCTED US TO CLB BACK TO 13000 FT. THE PROB AROSE BECAUSE OF CTLR ERROR. CONTRIBUTING FACTORS INCLUDE: SIMILAR CALL SIGNS, WX AND HOLDING PATTERN. CONFLICT WAS DISCOVERED VIA TCASII (GREAT TOOL). WE WERE AWARE OF THE OTHER ACR, ABC, AND VERY CONSCIOUS OF CTLR'S INSTRUCTIONS. HOLDINGS AND ALTS WERE READ BACK CLRLY AND DOUBLE-POINTING AT THE NEW MODE CTL PANEL ALT WAS ACCOMPLISHED.

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.