Narrative:

As we approached dupont VOR, FL230, 330 KTS, we were given clearance to cross somto intersection at 11000. This was acknowledged and read back, the captain began his descent. Then the following occurred in fairly rapid order: ATC advised us we had converging VFR traffic at 13500, 10 O'clock. ATC asked us if we wanted a turn or a vector. I asked the captain, he replied 'no,' I advised ATC 'no.' ATC yet again advised us we had converging VFR traffic at 13500, 10 O'clock, and asked us if we wanted to level off at 14000. I asked the captain, and he replied 'no,' and then stated he had the traffic. The so also reported he had the traffic. I advised ATC 'no.' we then got a TCASII TA 'traffic, traffic.' it showed the aircraft at 10 O'clock, 4-5 mi converging, approximately 1000 ft below us. I turned to the captain and assertively asked him if he had the traffic, he replied 'yes.' then the so leaned forward from his seat pointed his finger against the window and assertively asked the captain 'do you have that traffic?' the captain replied 'yes.' we received a TCASII RA 'monitor vertical speed -- monitor vertical speed.' the TCASII showed the aircraft at 10 O'clock, 2-3 mi, 400-500 ft below us, still converging. I again assertively asked the captain if he had the traffic, he replied 'yes.' the TCASII was red down, red 0-1500 up, and green 1500-2000 up, and stating, 'climb, climb now! -- Climb, climb now!' ATC was telling us to turn to the right, the TCASII showed the traffic at less than 1 mi, same altitude, converging. The captain ignored the command and only leveled the aircraft at 13500. We were still at 330 KTS, converging, he made no attempt to turn the aircraft. I finally got a visual on the aircraft. It was 200-300 ft from us at the same altitude, and in a 60-90 degree angle of bank turn to the left with a slight climb. Supplemental information from acn 214212: ATC called and advised of VFR traffic at 12500 ahead and to our left. I requested ATC to keep us advised of the traffic. ATC then advised that the traffic was climbing through 13300 and I observed my aircraft leaving 14700. After the second advisory I observed converging turboprop traffic at 10 O'clock and slightly below my aircraft. ATC advised that we could level off at 14000 if we desired. The TCASII was aurally calling for a climb to avoid the traffic. I elected to disregard the TCASII and continue descent with visual separation from the observed traffic. To have initiated climb at that point would have taken my aircraft through the projected course of the observed climbing traffic, lost my visual reference with the traffic, and, I believe, created a greater hazard than descending with visual separation. At about 1/2 mi separation, the observed aircraft initiated a left turn away from my aircraft.

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Original NASA ASRS Text

Title: NMAC.

Narrative: AS WE APCHED DUPONT VOR, FL230, 330 KTS, WE WERE GIVEN CLRNC TO CROSS SOMTO INTXN AT 11000. THIS WAS ACKNOWLEDGED AND READ BACK, THE CAPT BEGAN HIS DSCNT. THEN THE FOLLOWING OCCURRED IN FAIRLY RAPID ORDER: ATC ADVISED US WE HAD CONVERGING VFR TFC AT 13500, 10 O'CLOCK. ATC ASKED US IF WE WANTED A TURN OR A VECTOR. I ASKED THE CAPT, HE REPLIED 'NO,' I ADVISED ATC 'NO.' ATC YET AGAIN ADVISED US WE HAD CONVERGING VFR TFC AT 13500, 10 O'CLOCK, AND ASKED US IF WE WANTED TO LEVEL OFF AT 14000. I ASKED THE CAPT, AND HE REPLIED 'NO,' AND THEN STATED HE HAD THE TFC. THE SO ALSO RPTED HE HAD THE TFC. I ADVISED ATC 'NO.' WE THEN GOT A TCASII TA 'TFC, TFC.' IT SHOWED THE ACFT AT 10 O'CLOCK, 4-5 MI CONVERGING, APPROX 1000 FT BELOW US. I TURNED TO THE CAPT AND ASSERTIVELY ASKED HIM IF HE HAD THE TFC, HE REPLIED 'YES.' THEN THE SO LEANED FORWARD FROM HIS SEAT POINTED HIS FINGER AGAINST THE WINDOW AND ASSERTIVELY ASKED THE CAPT 'DO YOU HAVE THAT TFC?' THE CAPT REPLIED 'YES.' WE RECEIVED A TCASII RA 'MONITOR VERT SPD -- MONITOR VERT SPD.' THE TCASII SHOWED THE ACFT AT 10 O'CLOCK, 2-3 MI, 400-500 FT BELOW US, STILL CONVERGING. I AGAIN ASSERTIVELY ASKED THE CAPT IF HE HAD THE TFC, HE REPLIED 'YES.' THE TCASII WAS RED DOWN, RED 0-1500 UP, AND GREEN 1500-2000 UP, AND STATING, 'CLB, CLB NOW! -- CLB, CLB NOW!' ATC WAS TELLING US TO TURN TO THE R, THE TCASII SHOWED THE TFC AT LESS THAN 1 MI, SAME ALT, CONVERGING. THE CAPT IGNORED THE COMMAND AND ONLY LEVELED THE ACFT AT 13500. WE WERE STILL AT 330 KTS, CONVERGING, HE MADE NO ATTEMPT TO TURN THE ACFT. I FINALLY GOT A VISUAL ON THE ACFT. IT WAS 200-300 FT FROM US AT THE SAME ALT, AND IN A 60-90 DEG ANGLE OF BANK TURN TO THE L WITH A SLIGHT CLB. SUPPLEMENTAL INFO FROM ACN 214212: ATC CALLED AND ADVISED OF VFR TFC AT 12500 AHEAD AND TO OUR L. I REQUESTED ATC TO KEEP US ADVISED OF THE TFC. ATC THEN ADVISED THAT THE TFC WAS CLBING THROUGH 13300 AND I OBSERVED MY ACFT LEAVING 14700. AFTER THE SECOND ADVISORY I OBSERVED CONVERGING TURBOPROP TFC AT 10 O'CLOCK AND SLIGHTLY BELOW MY ACFT. ATC ADVISED THAT WE COULD LEVEL OFF AT 14000 IF WE DESIRED. THE TCASII WAS AURALLY CALLING FOR A CLB TO AVOID THE TFC. I ELECTED TO DISREGARD THE TCASII AND CONTINUE DSCNT WITH VISUAL SEPARATION FROM THE OBSERVED TFC. TO HAVE INITIATED CLB AT THAT POINT WOULD HAVE TAKEN MY ACFT THROUGH THE PROJECTED COURSE OF THE OBSERVED CLBING TFC, LOST MY VISUAL REF WITH THE TFC, AND, I BELIEVE, CREATED A GREATER HAZARD THAN DSNDING WITH VISUAL SEPARATION. AT ABOUT 1/2 MI SEPARATION, THE OBSERVED ACFT INITIATED A L TURN AWAY FROM MY ACFT.

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.