Narrative:

The sector was very busy at the time. Aircraft a was northbound, level FL290. Aircraft B was sbound, level FL280, but requesting FL310. The radar controller had vectored aircraft west of course for other traffic, therefore, she missed him in her scan and climbed aircraft B through his altitude. Aircraft a advised ATC he had responded to an RA and was now going back to FL290, but separation had already been lost. Busy traffic and new control equipment were contributing factors.

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Original NASA ASRS Text

Title: FLC OF A B737 DSNDED BACK TO ORIGINAL ASSIGNED ALT IN RESPONSE TO A TCASII RA CAUSED BY AN MD80 LEVEL AT A FLT LEVEL THROUGH WHICH THEY WERE CLBING.

Narrative: THE SECTOR WAS VERY BUSY AT THE TIME. ACFT A WAS NBOUND, LEVEL FL290. ACFT B WAS SBOUND, LEVEL FL280, BUT REQUESTING FL310. THE RADAR CTLR HAD VECTORED ACFT W OF COURSE FOR OTHER TFC, THEREFORE, SHE MISSED HIM IN HER SCAN AND CLBED ACFT B THROUGH HIS ALT. ACFT A ADVISED ATC HE HAD RESPONDED TO AN RA AND WAS NOW GOING BACK TO FL290, BUT SEPARATION HAD ALREADY BEEN LOST. BUSY TFC AND NEW CTL EQUIP WERE CONTRIBUTING FACTORS.

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.