Narrative:

Air carrier X departure from aranta on 250 degree heading with instructions to climb and maintain 10000 ft. Approaching level off we were given a turn to the south. Beginning turn and approximately 9500 ft we received a TCASII TA, immediately followed by a 'monitor vertical speed' command. First officer was flying and I as captain started looking outside for the traffic. We were facing into the sun so visibility was extremely poor. I looked to the TCASII display on the ACARS screen just as the command changed to 'climb, climb' and I saw a red target at 2 O'clock indicating 900 ft below our altitude and descending. Still could see nothing outside due to sun. TCASII RA changed to 'climb, crossing, climb.' our initial vertical speed for level off was less than 1000 FPM and during 'monitor vertical speed' command we were well within the required parameters. When command changed to 'climb, climb,' the green arc was about 2500 FPM climb command which the first officer who was flying immediately responded to. At about 10500 ft we saw DC9 air carrier Y at 2 O'clock high in a left turn to avoid us. We leveled off at 10800 ft and he passed approximately 200 ft above and 1/2 mi to the right. We then descended back to our assigned altitude of 10000 ft. The TCASII had been indicating, initially, an aircraft at 2 O'clock below our altitude when he was actually above us. The resulting TCASII commands took us toward him and with the sun preventing a visual sighting and our following the TCASII commands we actually decreased the separation instead of the desired affect of avoiding the conflict.

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Original NASA ASRS Text

Title: ACR X TCASII TA RA UNAUTH CLB THROUGH ASSIGNED ALT HAD LTSS FROM ACR Y. EVASIVE ACTION TAKEN.

Narrative: ACR X DEP FROM ARANTA ON 250 DEG HDG WITH INSTRUCTIONS TO CLB AND MAINTAIN 10000 FT. APCHING LEVEL OFF WE WERE GIVEN A TURN TO THE S. BEGINNING TURN AND APPROX 9500 FT WE RECEIVED A TCASII TA, IMMEDIATELY FOLLOWED BY A 'MONITOR VERT SPD' COMMAND. FO WAS FLYING AND I AS CAPT STARTED LOOKING OUTSIDE FOR THE TFC. WE WERE FACING INTO THE SUN SO VISIBILITY WAS EXTREMELY POOR. I LOOKED TO THE TCASII DISPLAY ON THE ACARS SCREEN JUST AS THE COMMAND CHANGED TO 'CLB, CLB' AND I SAW A RED TARGET AT 2 O'CLOCK INDICATING 900 FT BELOW OUR ALT AND DSNDING. STILL COULD SEE NOTHING OUTSIDE DUE TO SUN. TCASII RA CHANGED TO 'CLB, XING, CLB.' OUR INITIAL VERT SPD FOR LEVEL OFF WAS LESS THAN 1000 FPM AND DURING 'MONITOR VERT SPD' COMMAND WE WERE WELL WITHIN THE REQUIRED PARAMETERS. WHEN COMMAND CHANGED TO 'CLB, CLB,' THE GREEN ARC WAS ABOUT 2500 FPM CLB COMMAND WHICH THE FO WHO WAS FLYING IMMEDIATELY RESPONDED TO. AT ABOUT 10500 FT WE SAW DC9 ACR Y AT 2 O'CLOCK HIGH IN A L TURN TO AVOID US. WE LEVELED OFF AT 10800 FT AND HE PASSED APPROX 200 FT ABOVE AND 1/2 MI TO THE R. WE THEN DSNDED BACK TO OUR ASSIGNED ALT OF 10000 FT. THE TCASII HAD BEEN INDICATING, INITIALLY, AN ACFT AT 2 O'CLOCK BELOW OUR ALT WHEN HE WAS ACTUALLY ABOVE US. THE RESULTING TCASII COMMANDS TOOK US TOWARD HIM AND WITH THE SUN PREVENTING A VISUAL SIGHTING AND OUR FOLLOWING THE TCASII COMMANDS WE ACTUALLY DECREASED THE SEPARATION INSTEAD OF THE DESIRED AFFECT OF AVOIDING THE CONFLICT.

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.