Narrative:

Flight X en route at 14000 ft 15 NM from djb VOR on the 125 degree radial from the station. The TCAS system alerted us to a TA and a second later gave us an RA with a descent of 2000 FPM. I complied with TCAS instructions and began the descent. We visually made contact with the 2 small aircraft aircraft heading northeast in formation. ZOB gave us no traffic callouts before we had the RA. In compliance with TCAS instructions I descended the aircraft to approximately 13200 ft and made note the 2 aircraft passed overhead by 1400 ft according to the TCAS screen. After the 'clear of conflict' was given; we notified ATC that we were complying with an RA and were returning to our original altitude of 14000 ft. The 2 aircraft were VFR and were talking to a different center sector; the one south of our flight path. But according to our ATC controller; they did not display on his scope until about the same time we were complying with the RA. I want to make clear that there was no callout by ATC to watch for VFR traffic at our 10-11 O'clock position and that the TA to an RA happened very fast. Also; those 2 aircraft did not appear to be deviating at all from altitude and heading to avoid the conflict. Supplemental information from acn 790712: it was explained that before the controller was able to establish a data block to identify the aircraft; the RA event had occurred. Upon initial contact with the VFR aircraft; the controller did issue the VFR aircraft a TA as to our position; and one of the VFR's stated 'in sight.' at that time; we were in sight to the 2 VFR's; luckily due to our RA maneuver.

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Original NASA ASRS Text

Title: ACR AT 14000 FT WITH ZOB EXPERIENCED TCAS RA WITH UNREPORTED VFR TFC; ATC INDICATING VFR ID IMMEDIATELY PRIOR TO TCAS; ACFT IN AN ADJACENT SECTOR.

Narrative: FLT X ENRTE AT 14000 FT 15 NM FROM DJB VOR ON THE 125 DEG RADIAL FROM THE STATION. THE TCAS SYS ALERTED US TO A TA AND A SECOND LATER GAVE US AN RA WITH A DSCNT OF 2000 FPM. I COMPLIED WITH TCAS INSTRUCTIONS AND BEGAN THE DSCNT. WE VISUALLY MADE CONTACT WITH THE 2 SMA ACFT HEADING NE IN FORMATION. ZOB GAVE US NO TFC CALLOUTS BEFORE WE HAD THE RA. IN COMPLIANCE WITH TCAS INSTRUCTIONS I DSNDED THE ACFT TO APPROX 13200 FT AND MADE NOTE THE 2 ACFT PASSED OVERHEAD BY 1400 FT ACCORDING TO THE TCAS SCREEN. AFTER THE 'CLR OF CONFLICT' WAS GIVEN; WE NOTIFIED ATC THAT WE WERE COMPLYING WITH AN RA AND WERE RETURNING TO OUR ORIGINAL ALT OF 14000 FT. THE 2 ACFT WERE VFR AND WERE TALKING TO A DIFFERENT CTR SECTOR; THE ONE S OF OUR FLT PATH. BUT ACCORDING TO OUR ATC CTLR; THEY DID NOT DISPLAY ON HIS SCOPE UNTIL ABOUT THE SAME TIME WE WERE COMPLYING WITH THE RA. I WANT TO MAKE CLR THAT THERE WAS NO CALLOUT BY ATC TO WATCH FOR VFR TFC AT OUR 10-11 O'CLOCK POS AND THAT THE TA TO AN RA HAPPENED VERY FAST. ALSO; THOSE 2 ACFT DID NOT APPEAR TO BE DEVIATING AT ALL FROM ALT AND HDG TO AVOID THE CONFLICT. SUPPLEMENTAL INFO FROM ACN 790712: IT WAS EXPLAINED THAT BEFORE THE CTLR WAS ABLE TO ESTABLISH A DATA BLOCK TO IDENT THE ACFT; THE RA EVENT HAD OCCURRED. UPON INITIAL CONTACT WITH THE VFR ACFT; THE CTLR DID ISSUE THE VFR ACFT A TA AS TO OUR POS; AND ONE OF THE VFR'S STATED 'IN SIGHT.' AT THAT TIME; WE WERE IN SIGHT TO THE 2 VFR'S; LUCKILY DUE TO OUR RA MANEUVER.

Data retrieved from NASA's ASRS site as of May 2009 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.