Narrative:

Flight from roa to pit was assigned 7000 ft and level near pleez intersection on the nesto 2 arrival. It was XA30 and ZOB called traffic 10 O'clock, 10 mi, 7300 ft unverified. We had no indication on our TCASII and the sun was setting directly where traffic had been issued. We stated 'no contact.' moments later, ATC called traffic 11 O'clock position, 5 mi, 7300 ft. At that point we did get a target in blue on our TCASII, but we were unable to obtain visual contact. The target turned amber, a TCASII alert was issued. ATC called traffic 1 mi 7300 ft. Then the TCASII gave an RA 'monitor vertical speed' command, followed immediately by another RA 'descend now!' I clicked off the autoplt and followed the vertical needle down 1700 FPM and told my first officer to get lower, tell ATC we are descending. At 6300 ft, I saw a cessna 310, white with red trim, pass overhead by approximately 800 ft. ATC told us to maintain 6000 ft and we set 6000 ft. The clear of conflict command and we leveled at 6000 ft with autoplt back on. This is a situation that could have been resolved by ATC issuing a turn or lower altitude to avoid a dangerous situation. If we had seem the target, we would have been told to maintain visual separation. Is 300 ft adequate separation? How could I have avoided this aircraft with a hard altitude of 7000 ft? What was center thinking?

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Original NASA ASRS Text

Title: ACR FLC COMPLIES WITH TCASII RA UNDER ZOB CTL. TA'S GIVEN, BUT NO CONFLICT RESOLUTION ISSUED.

Narrative: FLT FROM ROA TO PIT WAS ASSIGNED 7000 FT AND LEVEL NEAR PLEEZ INTXN ON THE NESTO 2 ARR. IT WAS XA30 AND ZOB CALLED TFC 10 O'CLOCK, 10 MI, 7300 FT UNVERIFIED. WE HAD NO INDICATION ON OUR TCASII AND THE SUN WAS SETTING DIRECTLY WHERE TFC HAD BEEN ISSUED. WE STATED 'NO CONTACT.' MOMENTS LATER, ATC CALLED TFC 11 O'CLOCK POS, 5 MI, 7300 FT. AT THAT POINT WE DID GET A TARGET IN BLUE ON OUR TCASII, BUT WE WERE UNABLE TO OBTAIN VISUAL CONTACT. THE TARGET TURNED AMBER, A TCASII ALERT WAS ISSUED. ATC CALLED TFC 1 MI 7300 FT. THEN THE TCASII GAVE AN RA 'MONITOR VERT SPD' COMMAND, FOLLOWED IMMEDIATELY BY ANOTHER RA 'DSND NOW!' I CLICKED OFF THE AUTOPLT AND FOLLOWED THE VERT NEEDLE DOWN 1700 FPM AND TOLD MY FO TO GET LOWER, TELL ATC WE ARE DSNDING. AT 6300 FT, I SAW A CESSNA 310, WHITE WITH RED TRIM, PASS OVERHEAD BY APPROX 800 FT. ATC TOLD US TO MAINTAIN 6000 FT AND WE SET 6000 FT. THE CLR OF CONFLICT COMMAND AND WE LEVELED AT 6000 FT WITH AUTOPLT BACK ON. THIS IS A SIT THAT COULD HAVE BEEN RESOLVED BY ATC ISSUING A TURN OR LOWER ALT TO AVOID A DANGEROUS SIT. IF WE HAD SEEM THE TARGET, WE WOULD HAVE BEEN TOLD TO MAINTAIN VISUAL SEPARATION. IS 300 FT ADEQUATE SEPARATION? HOW COULD I HAVE AVOIDED THIS ACFT WITH A HARD ALT OF 7000 FT? WHAT WAS CTR THINKING?

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.