Narrative:

Departure climb to 8000 ft MSL, per SID and ATC departure control. I was hand flying aircraft to 8000 ft. ATC advised leveloff at 8000 ft because 2 targets overhead at 9000 ft MSL. At approximately 7500 ft MSL the TCASII 'popped up' an RA directing a climb at plus 2500 FPM. Multiple flight display/TCASII display showed a red boxed target at same relative altitude. The RA advised 'increase climb' and red band on vsi to plus 2500 ft climb rate. I leveled off at 8200 ft (not 8000 ft) just in case there was actually traffic at 8000 ft. The copilot asked ATC to verify traffic in our vicinity because we had an RA (which I did not believe and couldn't respond to because I had visual on 1 of the 2 aircraft that had been called by ATC. If I had responded to the RA, I most certainly would have hit the traffic). The visual RA remained until I cycled the unit off and on. The TCASII was reacting to traffic that was not there. It was as though the TCASII was reacting to itself as another target. The flight was continued as a non TCASII equipped aircraft.

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Original NASA ASRS Text

Title: ALTDEV ALT OVERSHOT IN CLB BY PIC DUE TO FALSE TCASII RA.

Narrative: DEP CLB TO 8000 FT MSL, PER SID AND ATC DEP CTL. I WAS HAND FLYING ACFT TO 8000 FT. ATC ADVISED LEVELOFF AT 8000 FT BECAUSE 2 TARGETS OVERHEAD AT 9000 FT MSL. AT APPROX 7500 FT MSL THE TCASII 'POPPED UP' AN RA DIRECTING A CLB AT PLUS 2500 FPM. MULTIPLE FLT DISPLAY/TCASII DISPLAY SHOWED A RED BOXED TARGET AT SAME RELATIVE ALT. THE RA ADVISED 'INCREASE CLB' AND RED BAND ON VSI TO PLUS 2500 FT CLB RATE. I LEVELED OFF AT 8200 FT (NOT 8000 FT) JUST IN CASE THERE WAS ACTUALLY TFC AT 8000 FT. THE COPLT ASKED ATC TO VERIFY TFC IN OUR VICINITY BECAUSE WE HAD AN RA (WHICH I DID NOT BELIEVE AND COULDN'T RESPOND TO BECAUSE I HAD VISUAL ON 1 OF THE 2 ACFT THAT HAD BEEN CALLED BY ATC. IF I HAD RESPONDED TO THE RA, I MOST CERTAINLY WOULD HAVE HIT THE TFC). THE VISUAL RA REMAINED UNTIL I CYCLED THE UNIT OFF AND ON. THE TCASII WAS REACTING TO TFC THAT WAS NOT THERE. IT WAS AS THOUGH THE TCASII WAS REACTING TO ITSELF AS ANOTHER TARGET. THE FLT WAS CONTINUED AS A NON TCASII EQUIPPED ACFT.

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.