Narrative:

We were descending through 16000 ft when we were issued a TA by ZBW. The traffic was reported as a saab 340 at 10 O'clock and 15000 ft, converging. Both myself and the PNF had the traffic in sight as the visibility was exceptionally good. We reported the traffic in sight and the ZBW controller responded by instructing us to maintain visual separation with the traffic and descend and maintain 13000 ft. We accepted the clearance. It was evident to both myself and the PNF that we would pass ahead and above the converging traffic. As we were descending through 15500 ft (and ahead of the traffic) the crew of the saab reported to ZBW that they had obtained an RA from TCASII and had descended. ZBW replied that we had accepted a clearance for visual separation and that we were passing clear. It is unknown to us as to exactly what action the saab took as a result of their RA. (Our aircraft is not TCASII equipped.) it is/was our opinion that the RA was unnecessary as we were visual with the traffic and were maintaining visual clearance. There was never a question of any conflict in our opinion. No action was taken on our part. ZBW made no further comments about what had happened. I do not know if the crew of the saab had us in sight or not. Duty time for our crew was not a factor, nor was fatigue. I do not have any reason to believe that we made any errors as to the judgement of distance or altitude.

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Original NASA ASRS Text

Title: SAAB 340 FLC DSNDED IN RESPONSE TO A TCASII RA CAUSED BY RPTR'S IA1124 EXECUTIVE JET DSNDING OVERHEAD OF THE SAAB 340 WHICH WAS ON A CONVERGING COURSE.

Narrative: WE WERE DSNDING THROUGH 16000 FT WHEN WE WERE ISSUED A TA BY ZBW. THE TFC WAS RPTED AS A SAAB 340 AT 10 O'CLOCK AND 15000 FT, CONVERGING. BOTH MYSELF AND THE PNF HAD THE TFC IN SIGHT AS THE VISIBILITY WAS EXCEPTIONALLY GOOD. WE RPTED THE TFC IN SIGHT AND THE ZBW CTLR RESPONDED BY INSTRUCTING US TO MAINTAIN VISUAL SEPARATION WITH THE TFC AND DSND AND MAINTAIN 13000 FT. WE ACCEPTED THE CLRNC. IT WAS EVIDENT TO BOTH MYSELF AND THE PNF THAT WE WOULD PASS AHEAD AND ABOVE THE CONVERGING TFC. AS WE WERE DSNDING THROUGH 15500 FT (AND AHEAD OF THE TFC) THE CREW OF THE SAAB RPTED TO ZBW THAT THEY HAD OBTAINED AN RA FROM TCASII AND HAD DSNDED. ZBW REPLIED THAT WE HAD ACCEPTED A CLRNC FOR VISUAL SEPARATION AND THAT WE WERE PASSING CLR. IT IS UNKNOWN TO US AS TO EXACTLY WHAT ACTION THE SAAB TOOK AS A RESULT OF THEIR RA. (OUR ACFT IS NOT TCASII EQUIPPED.) IT IS/WAS OUR OPINION THAT THE RA WAS UNNECESSARY AS WE WERE VISUAL WITH THE TFC AND WERE MAINTAINING VISUAL CLRNC. THERE WAS NEVER A QUESTION OF ANY CONFLICT IN OUR OPINION. NO ACTION WAS TAKEN ON OUR PART. ZBW MADE NO FURTHER COMMENTS ABOUT WHAT HAD HAPPENED. I DO NOT KNOW IF THE CREW OF THE SAAB HAD US IN SIGHT OR NOT. DUTY TIME FOR OUR CREW WAS NOT A FACTOR, NOR WAS FATIGUE. I DO NOT HAVE ANY REASON TO BELIEVE THAT WE MADE ANY ERRORS AS TO THE JUDGEMENT OF DISTANCE OR ALT.

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.