Narrative:

While flying at an altitude of 8000 ft, approximately 5 mi north of madison VOR, going direct to madison VOR, bradley approach reported a light aircraft at 11 O'clock and 2 mi, 8500 ft. There was a cumulus buildup between us and the conflicting traffic. We observed the aircraft on TCASII, however, our TCASII system are currently not authorized for RA, thus, no RA's were given by the TCASII. The other aircraft then started a descent down to 8300 ft and continued its descent and southwest course across our flight path. Bradley controller called the other aircraft twice, the second time very frantically. The controller then told us the traffic wasn't answering him. We were looking for him when at the last min my first officer saw him and pointed to our 10 O'clock position. Out of my periphery I saw an aircraft heading for us. I pulled the aircraft up to 8500 ft and avoided a collision. The abrupt maneuver resulted in a flight attendant falling down in the galley area, severely injuring her ankle. The light aircraft passed immediately behind us and continued on its way, VFR. Bradley ATC was notified of my intent to file a near miss report. Having a fully operational TCASII would certainly have helped in this event. It would have given us an RA much sooner and avoided the abrupt maneuver. We never saw the light aircraft until he came around from behind the buildup. Also, the frantic chatter on the radio was distracting to say the least and inhibited us from calling the controller to get more information from him. The VFR aircraft later said he had us in visual contact but couldn't say so because he couldn't transmit due to the controller constantly talking. That, however, doesn't excuse the VFR aircraft from straying from his VFR cruising altitude.

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Original NASA ASRS Text

Title: ALTDEV ALT EXCURSION AFTER RECEIVING TCASII TA.

Narrative: WHILE FLYING AT AN ALT OF 8000 FT, APPROX 5 MI N OF MADISON VOR, GOING DIRECT TO MADISON VOR, BRADLEY APCH RPTED A LIGHT ACFT AT 11 O'CLOCK AND 2 MI, 8500 FT. THERE WAS A CUMULUS BUILDUP BTWN US AND THE CONFLICTING TFC. WE OBSERVED THE ACFT ON TCASII, HOWEVER, OUR TCASII SYS ARE CURRENTLY NOT AUTHORIZED FOR RA, THUS, NO RA'S WERE GIVEN BY THE TCASII. THE OTHER ACFT THEN STARTED A DSCNT DOWN TO 8300 FT AND CONTINUED ITS DSCNT AND SW COURSE ACROSS OUR FLT PATH. BRADLEY CTLR CALLED THE OTHER ACFT TWICE, THE SECOND TIME VERY FRANTICALLY. THE CTLR THEN TOLD US THE TFC WASN'T ANSWERING HIM. WE WERE LOOKING FOR HIM WHEN AT THE LAST MIN MY FO SAW HIM AND POINTED TO OUR 10 O'CLOCK POS. OUT OF MY PERIPHERY I SAW AN ACFT HDG FOR US. I PULLED THE ACFT UP TO 8500 FT AND AVOIDED A COLLISION. THE ABRUPT MANEUVER RESULTED IN A FLT ATTENDANT FALLING DOWN IN THE GALLEY AREA, SEVERELY INJURING HER ANKLE. THE LIGHT ACFT PASSED IMMEDIATELY BEHIND US AND CONTINUED ON ITS WAY, VFR. BRADLEY ATC WAS NOTIFIED OF MY INTENT TO FILE A NEAR MISS RPT. HAVING A FULLY OPERATIONAL TCASII WOULD CERTAINLY HAVE HELPED IN THIS EVENT. IT WOULD HAVE GIVEN US AN RA MUCH SOONER AND AVOIDED THE ABRUPT MANEUVER. WE NEVER SAW THE LIGHT ACFT UNTIL HE CAME AROUND FROM BEHIND THE BUILDUP. ALSO, THE FRANTIC CHATTER ON THE RADIO WAS DISTRACTING TO SAY THE LEAST AND INHIBITED US FROM CALLING THE CTLR TO GET MORE INFO FROM HIM. THE VFR ACFT LATER SAID HE HAD US IN VISUAL CONTACT BUT COULDN'T SAY SO BECAUSE HE COULDN'T XMIT DUE TO THE CTLR CONSTANTLY TALKING. THAT, HOWEVER, DOESN'T EXCUSE THE VFR ACFT FROM STRAYING FROM HIS VFR CRUISING 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.