Narrative:

During our descent into psp, we were being vectored for a visual approach. As we were leveling off at 8000 ft (assigned altitude), we noticed a beechcraft baron (yellow/white) at our 11 O'clock position, opposite direction, same altitude, and approximately 500 ft away. We turned to our right and the baron turned to his right. We told the controller about the evasive action to avoid the traffic and the controller's reply was that he does not show any traffic that was in conflict with us. However, when we contacted the following controller, he concurred that by this stage, he was showing a target at our altitude and 4 mi behind us. After landing, I called the TRACON facility and supervisor by telephone, who pointed out that, due to the windmills in certain areas, radar coverage is blocked. He also indicated that the baron possibly turned his transponder on after the traffic conflict.

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Original NASA ASRS Text

Title: COMMUTER FLT HAS NMAC WITH LIGHT TWIN WHILE APCHING PSP FOR LNDG.

Narrative: DURING OUR DSCNT INTO PSP, WE WERE BEING VECTORED FOR A VISUAL APCH. AS WE WERE LEVELING OFF AT 8000 FT (ASSIGNED ALT), WE NOTICED A BEECHCRAFT BARON (YELLOW/WHITE) AT OUR 11 O'CLOCK POS, OPPOSITE DIRECTION, SAME ALT, AND APPROX 500 FT AWAY. WE TURNED TO OUR R AND THE BARON TURNED TO HIS R. WE TOLD THE CTLR ABOUT THE EVASIVE ACTION TO AVOID THE TFC AND THE CTLR'S REPLY WAS THAT HE DOES NOT SHOW ANY TFC THAT WAS IN CONFLICT WITH US. HOWEVER, WHEN WE CONTACTED THE FOLLOWING CTLR, HE CONCURRED THAT BY THIS STAGE, HE WAS SHOWING A TARGET AT OUR ALT AND 4 MI BEHIND US. AFTER LNDG, I CALLED THE TRACON FACILITY AND SUPVR BY TELEPHONE, WHO POINTED OUT THAT, DUE TO THE WINDMILLS IN CERTAIN AREAS, RADAR COVERAGE IS BLOCKED. HE ALSO INDICATED THAT THE BARON POSSIBLY TURNED HIS XPONDER ON AFTER THE TFC 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.