Narrative:

As we were leaving 5000 ft, departure control advised us of traffic at 12 O'clock at 6500 ft, headed east. We were headed west looking into the sun, so we didn't pick up the traffic. Departure advised us to stop our climb at 6000 ft until clear of traffic. I stopped the climb at 5600 ft and looked for the traffic. The TCASII told us to descend and the target was at 6200 ft, 4 mi at 12 O'clock. I finally spotted the single engine bonanza headed east, slightly above our altitude. He must have spotted us because he started a dive with no turn. When I could tell that he was descending, I started a climb. The aircraft passed underneath us by 100-200 ft. (The TCASII was telling us to descend and that would have been the wrong action.)

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Original NASA ASRS Text

Title: AN ACR MLG HAD AN NMAC WITH A BONANZA. THE ACR'S TCASII WAS TELLING IT TO DSND WHEN CLB WAS THE BETTER SOLUTION WHEN ACFT Y MADE A MOVE. VISIBILITY REDUCED SUN POS.

Narrative: AS WE WERE LEAVING 5000 FT, DEP CTL ADVISED US OF TFC AT 12 O'CLOCK AT 6500 FT, HEADED E. WE WERE HEADED W LOOKING INTO THE SUN, SO WE DIDN'T PICK UP THE TFC. DEP ADVISED US TO STOP OUR CLB AT 6000 FT UNTIL CLR OF TFC. I STOPPED THE CLB AT 5600 FT AND LOOKED FOR THE TFC. THE TCASII TOLD US TO DSND AND THE TARGET WAS AT 6200 FT, 4 MI AT 12 O'CLOCK. I FINALLY SPOTTED THE SINGLE ENG BONANZA HEADED E, SLIGHTLY ABOVE OUR ALT. HE MUST HAVE SPOTTED US BECAUSE HE STARTED A DIVE WITH NO TURN. WHEN I COULD TELL THAT HE WAS DSNDING, I STARTED A CLB. THE ACFT PASSED UNDERNEATH US BY 100-200 FT. (THE TCASII WAS TELLING US TO DSND AND THAT WOULD HAVE BEEN THE WRONG ACTION.)

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.