Narrative:

On jun/xx/97 operating a scheduled flight from lga to ack, new york approach cleared us to bdr VOR and also cleared us to climb to 15000 ft. At XA37Z, climbing out of 14200 ft, and 7 mi southwest of bdr, our TCASII alerted us of impending traffic at our 5 O'clock position (2-3 mi and 700-800 ft below us and climbing). We were then advised of the traffic by new york, and told to descend back to 11000 ft. We then told new york we were going back down to 11000 ft. My first officer then noticed a B747 type aircraft on our 5 O'clock position. He also noticed that the closure rate from the B747 was too great and realized that if we descended to 11000 ft, we would descend into the aircraft. The closure rate from the B747 forced us to take evasive action, by turning to the left to avoid a possible midair collision. The first officer told me that air carrier flight rr (the B747) passed at our altitude and was 1/4 - 1/2 mi from us vertically. The crew of air carrier told approach that they passed us with 400 meters of separation. I also told approach we had a close call. Upon reaching ack I called new york approach and told them of the situation, and how if we descended to 11000 ft we would have possibly descended into the B747. They told me that they were investigating the situation. I believe approach should have descended air carrier back to 11000 ft, because they were behind and below us, and should have had us to continue our climb to 15000 ft.

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Original NASA ASRS Text

Title: AS A BE1900 IS CLBING TO ALT UNDER THE CTL OF N90, A B747 IS SEEN APCHING FROM BELOW AND BEHIND. THE BE1900 IS COMMANDED TO DSND TO AVOID THE B747 BUT THE FLC CAN SEE THAT A DSCNT WOULD BE INTO THE B747. BE1900 FLC COMPLAINS TO N90 THAT IT WOULD HAVE BEEN BETTER IF THEY CLBED AND THE LOSS OF SEPARATION WAS THE FAULT OF ATC.

Narrative: ON JUN/XX/97 OPERATING A SCHEDULED FLT FROM LGA TO ACK, NEW YORK APCH CLRED US TO BDR VOR AND ALSO CLRED US TO CLB TO 15000 FT. AT XA37Z, CLBING OUT OF 14200 FT, AND 7 MI SW OF BDR, OUR TCASII ALERTED US OF IMPENDING TFC AT OUR 5 O'CLOCK POS (2-3 MI AND 700-800 FT BELOW US AND CLBING). WE WERE THEN ADVISED OF THE TFC BY NEW YORK, AND TOLD TO DSND BACK TO 11000 FT. WE THEN TOLD NEW YORK WE WERE GOING BACK DOWN TO 11000 FT. MY FO THEN NOTICED A B747 TYPE ACFT ON OUR 5 O'CLOCK POS. HE ALSO NOTICED THAT THE CLOSURE RATE FROM THE B747 WAS TOO GREAT AND REALIZED THAT IF WE DSNDED TO 11000 FT, WE WOULD DSND INTO THE ACFT. THE CLOSURE RATE FROM THE B747 FORCED US TO TAKE EVASIVE ACTION, BY TURNING TO THE L TO AVOID A POSSIBLE MIDAIR COLLISION. THE FO TOLD ME THAT ACR FLT RR (THE B747) PASSED AT OUR ALT AND WAS 1/4 - 1/2 MI FROM US VERTLY. THE CREW OF ACR TOLD APCH THAT THEY PASSED US WITH 400 METERS OF SEPARATION. I ALSO TOLD APCH WE HAD A CLOSE CALL. UPON REACHING ACK I CALLED NEW YORK APCH AND TOLD THEM OF THE SIT, AND HOW IF WE DSNDED TO 11000 FT WE WOULD HAVE POSSIBLY DSNDED INTO THE B747. THEY TOLD ME THAT THEY WERE INVESTIGATING THE SIT. I BELIEVE APCH SHOULD HAVE DSNDED ACR BACK TO 11000 FT, BECAUSE THEY WERE BEHIND AND BELOW US, AND SHOULD HAVE HAD US TO CONTINUE OUR CLB TO 15000 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.