Narrative:

Altitude deviation in response to RA. ATC called the traffic out to us. It was a small private jet. We saw its display on TCASII, but had no visual tally. ATC said the small jet had us in sight. At the time, we were climbing at 1000 FPM. The initial RA directed us to reduce vertical speed to 300 FPM. Soon thereafter, it issued a 'descend now' warning and directed a 1000 FPM descent. We complied with the RA and notified ATC of our action. We complied with the RA and notified ATC of our action. We estimate 400 ft vertical separation from the traffic at 1 NM, and 1000 ft vertical separation as it passed overhead. We descended approximately 600 ft during the RA maneuver.

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Original NASA ASRS Text

Title: AN ACR B727 FLEW A TCASII RA NEAR IAD, VA, TO AVOID RPTED TFC THAT WAS NOT IN SIGHT, BUT WHO HAD RPTED THE B727 IN SIGHT.

Narrative: ALTDEV IN RESPONSE TO RA. ATC CALLED THE TFC OUT TO US. IT WAS A SMALL PVT JET. WE SAW ITS DISPLAY ON TCASII, BUT HAD NO VISUAL TALLY. ATC SAID THE SMALL JET HAD US IN SIGHT. AT THE TIME, WE WERE CLBING AT 1000 FPM. THE INITIAL RA DIRECTED US TO REDUCE VERT SPD TO 300 FPM. SOON THEREAFTER, IT ISSUED A 'DSND NOW' WARNING AND DIRECTED A 1000 FPM DSCNT. WE COMPLIED WITH THE RA AND NOTIFIED ATC OF OUR ACTION. WE COMPLIED WITH THE RA AND NOTIFIED ATC OF OUR ACTION. WE ESTIMATE 400 FT VERT SEPARATION FROM THE TFC AT 1 NM, AND 1000 FT VERT SEPARATION AS IT PASSED OVERHEAD. WE DSNDED APPROX 600 FT DURING THE RA MANEUVER.

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.