Narrative:

ZOB issued a descent from FL310 to FL280. TCASII warning for traffic at FL290 (aircraft Y) opposite direction. RA to climb. When our aircraft (X) was at FL290, conflict traffic was 10 mi away. We complied with resolution and ATC clearance to FL310, the traffic passed 1700 ft below our aircraft. Supplemental information from acn 452073: carj was given descent to FL280 for converging traffic at FL310. Head on traffic at FL290 was overlooked. Carj jet could have been vectored to assure separation from the other aircraft at FL310. I thought aircraft at FL310 were closer than they actually were after replaying the incident/traffic.

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Original NASA ASRS Text

Title: CARJ INITIATES TCASII CLB MANEUVER DUE TO OPPOSITE DIRECTION TFC PASSING AT SAME ALT.

Narrative: ZOB ISSUED A DSCNT FROM FL310 TO FL280. TCASII WARNING FOR TFC AT FL290 (ACFT Y) OPPOSITE DIRECTION. RA TO CLB. WHEN OUR ACFT (X) WAS AT FL290, CONFLICT TFC WAS 10 MI AWAY. WE COMPLIED WITH RESOLUTION AND ATC CLRNC TO FL310, THE TFC PASSED 1700 FT BELOW OUR ACFT. SUPPLEMENTAL INFO FROM ACN 452073: CARJ WAS GIVEN DSCNT TO FL280 FOR CONVERGING TFC AT FL310. HEAD ON TFC AT FL290 WAS OVERLOOKED. CARJ JET COULD HAVE BEEN VECTORED TO ASSURE SEPARATION FROM THE OTHER ACFT AT FL310. I THOUGHT ACFT AT FL310 WERE CLOSER THAN THEY ACTUALLY WERE AFTER REPLAYING THE INCIDENT/TFC.

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.