Narrative:

Sector exceeded established saturation parameters at the time of the incident, however, that was not a causal factor, it merely precluded the issuance of TA or non-merging targets. A BA46 air carrier at FL270 experienced a TCASII monitor error to reduce rate of climb while the aircraft was in level flight, which caused the B712 to get a TCASII alert and climb from FL280 to FL290. The B712 pilot advised ATC that he was in a TCASII climb. ATC advised the B712 pilot to maintain his altitude and issued converging traffic (A319 at FL290), and the BA46 traffic at FL220. The B712 pilot advised he was leaving FL290 for FL280. ATC issued an immediate 90 degree right turn to the A319, who in turn advised that he had the B712 traffic in sight and was responding to a TCASII alert. ATC advised the A319 to return to FL290 as soon as possible.

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Original NASA ASRS Text

Title: ZKC CTLR EXPERIENCED TCASII RA EVENT RESULTING IN LOSS OF SEPARATION.

Narrative: SECTOR EXCEEDED ESTABLISHED SATURATION PARAMETERS AT THE TIME OF THE INCIDENT, HOWEVER, THAT WAS NOT A CAUSAL FACTOR, IT MERELY PRECLUDED THE ISSUANCE OF TA OR NON-MERGING TARGETS. A BA46 AIR CARRIER AT FL270 EXPERIENCED A TCASII MONITOR ERROR TO REDUCE RATE OF CLB WHILE THE ACFT WAS IN LEVEL FLT, WHICH CAUSED THE B712 TO GET A TCASII ALERT AND CLB FROM FL280 TO FL290. THE B712 PLT ADVISED ATC THAT HE WAS IN A TCASII CLB. ATC ADVISED THE B712 PLT TO MAINTAIN HIS ALT AND ISSUED CONVERGING TFC (A319 AT FL290), AND THE BA46 TFC AT FL220. THE B712 PLT ADVISED HE WAS LEAVING FL290 FOR FL280. ATC ISSUED AN IMMEDIATE 90 DEG R TURN TO THE A319, WHO IN TURN ADVISED THAT HE HAD THE B712 TFC IN SIGHT AND WAS RESPONDING TO A TCASII ALERT. ATC ADVISED THE A319 TO RETURN TO FL290 AS SOON AS POSSIBLE.

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.