Narrative:

During descent to bdl in ceiling and visibility unlimited, TCASII was on and in RA/TA mode. Passing 9000 ft. ATC advised traffic at 11 O'clock, 7 mi, northbound at 6400 ft, unconfirmed. Next call ATC: traffic 10:30, 3 mi, eastbound. I extended the wingtip landing lights and continued visual scan. I also disengaged the autoplt to enable evasive action if warranted. Next: TCASII annunciated traffic at 10:30 and -1100 ft. Still unable to find the traffic. Another ATC advisement of traffic as we passed through 7000 ft. I assumed we had cleared the traffic (traffic behind us). As we had no contact/visual sighting and the conflicting aircraft was close to our altitude in clear air. As we continued through 6700 ft a TCASII resolution was triggered. TCASII advised, 'climb, climb' and indicated 1500 FPM climb which was immediately followed. As we reached 7000 ft level off was indicated. Flight continued uneventfully to bdl. Conclusions and analysis: I believe that bdl TRACON misjudged our vertical and horizontal flight path. His expectation was that we would have passed overhead the traffic which was at an unconfirmed altitude. He relied on this to achieve separation. No vectors were given to assure horizontal separation. I relied on visually sighting the traffic the WX was so good. As a result I did not request a heading to assure separation. I relied on bdl to provide horizontal separation in the event visual sighting was not achieved. My normal descent profile is 240 KTS IAS/2200-2500 FPM. During discussion of the event with bdl TRACON the controller stated our ground speed was 270 KTS. I can only assume that the aircraft was trimmed slightly nose down and as I became intent on the traffic I allowed the speed to build up (although I can hardly believe 270 KTS). I may have pushed the nose down in an attempt to increase the visual scan area. This would have created a rapid descent which eliminated the required vertical separation. Conclusion: in the future I will allow or accept only horizontal separation with VFR/IFR traffic at unconfirmed altitudes. If not offered, I will request the separation. With the information the controller has on the TRACON display, he was in a position to have offered a positive resolution well before the situation became critical. I would recommend an earlier initiative on the part of the controller.

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Original NASA ASRS Text

Title: ACR HAS TCASII RA ON DSCNT, CLBS.

Narrative: DURING DSCNT TO BDL IN CEILING AND VISIBILITY UNLIMITED, TCASII WAS ON AND IN RA/TA MODE. PASSING 9000 FT. ATC ADVISED TFC AT 11 O'CLOCK, 7 MI, NBOUND AT 6400 FT, UNCONFIRMED. NEXT CALL ATC: TFC 10:30, 3 MI, EBOUND. I EXTENDED THE WINGTIP LNDG LIGHTS AND CONTINUED VISUAL SCAN. I ALSO DISENGAGED THE AUTOPLT TO ENABLE EVASIVE ACTION IF WARRANTED. NEXT: TCASII ANNUNCIATED TFC AT 10:30 AND -1100 FT. STILL UNABLE TO FIND THE TFC. ANOTHER ATC ADVISEMENT OF TFC AS WE PASSED THROUGH 7000 FT. I ASSUMED WE HAD CLRED THE TFC (TFC BEHIND US). AS WE HAD NO CONTACT/VISUAL SIGHTING AND THE CONFLICTING ACFT WAS CLOSE TO OUR ALT IN CLR AIR. AS WE CONTINUED THROUGH 6700 FT A TCASII RESOLUTION WAS TRIGGERED. TCASII ADVISED, 'CLB, CLB' AND INDICATED 1500 FPM CLB WHICH WAS IMMEDIATELY FOLLOWED. AS WE REACHED 7000 FT LEVEL OFF WAS INDICATED. FLT CONTINUED UNEVENTFULLY TO BDL. CONCLUSIONS AND ANALYSIS: I BELIEVE THAT BDL TRACON MISJUDGED OUR VERT AND HORIZ FLT PATH. HIS EXPECTATION WAS THAT WE WOULD HAVE PASSED OVERHEAD THE TFC WHICH WAS AT AN UNCONFIRMED ALT. HE RELIED ON THIS TO ACHIEVE SEPARATION. NO VECTORS WERE GIVEN TO ASSURE HORIZ SEPARATION. I RELIED ON VISUALLY SIGHTING THE TFC THE WX WAS SO GOOD. AS A RESULT I DID NOT REQUEST A HDG TO ASSURE SEPARATION. I RELIED ON BDL TO PROVIDE HORIZ SEPARATION IN THE EVENT VISUAL SIGHTING WAS NOT ACHIEVED. MY NORMAL DSCNT PROFILE IS 240 KTS IAS/2200-2500 FPM. DURING DISCUSSION OF THE EVENT WITH BDL TRACON THE CTLR STATED OUR GND SPD WAS 270 KTS. I CAN ONLY ASSUME THAT THE ACFT WAS TRIMMED SLIGHTLY NOSE DOWN AND AS I BECAME INTENT ON THE TFC I ALLOWED THE SPD TO BUILD UP (ALTHOUGH I CAN HARDLY BELIEVE 270 KTS). I MAY HAVE PUSHED THE NOSE DOWN IN AN ATTEMPT TO INCREASE THE VISUAL SCAN AREA. THIS WOULD HAVE CREATED A RAPID DSCNT WHICH ELIMINATED THE REQUIRED VERT SEPARATION. CONCLUSION: IN THE FUTURE I WILL ALLOW OR ACCEPT ONLY HORIZ SEPARATION WITH VFR/IFR TFC AT UNCONFIRMED ALTS. IF NOT OFFERED, I WILL REQUEST THE SEPARATION. WITH THE INFO THE CTLR HAS ON THE TRACON DISPLAY, HE WAS IN A POS TO HAVE OFFERED A POSITIVE RESOLUTION WELL BEFORE THE SITUATION BECAME CRITICAL. I WOULD RECOMMEND AN EARLIER INITIATIVE ON THE PART OF THE CTLR.

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.