A 'H25B' CREW EXPERIENCED A TCAS 'RA' RELATIVE TO A (R/C) REMOTE CONTROLLED ACFT.

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ON FINAL APCH FOR RWY 17L AT CENTENNIAL ARPT (KAPA) DURING VMC CONDITIONS; WE WERE CLRED TO LAND 17L BY APA TWR CTLR. AS WE TURNED FROM BASE TO FINAL; I SAW A REMOTE CONTROL MODEL AIRPLANE (YELLOW) FLYING ABOUT 200 FT BELOW AT A MODEL AIRPLANE PARK WITH HARD SURFACE RWYS. WHEN WE WERE DIRECTLY OVER THE R/C MODEL AIRPLANE WE GOT A TCAS RESOLUTION ADVISORY (RA)-'MONITOR VERIAL DSCNT.' BECAUSE WE HAD VISUAL CONTACT WITH THE MODEL A/C; AND WERE CLRED TO LAND WITH NO OTHER RPTED TFC; I CONTINUED THE APCH AND LNDG. WHEN WE ADVISED THE GND CTLR OF THE TCAS R/A HE SUGGESTED WE FILE THIS NASA REPORT. THIS INCIDENT IS THE FORTH TIME I HAVE RECEIVED A TCAS R/A; THE LAST THREE RESULTED IN THREE GO-AROUNDS. MY SUSPECTION IS THAT THE R/C TRANSMITTER FREQUENCIES ARE CAUSING ANOMALOUS TCAS R/A'S. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED OVER THE PAST 4 TO 5 YRS HE HAS EXECUTED 4 OR 5 GO-AROUNDS ASSOCIATED WITH TCAS 'RA'S'. ALL TAKING PLACE IN THE VICINITY OF CHERRY CREEK LAKE; SITE OF A R/C ACFT ARPT. ALTHOUGH IN 'VMC' DURING THESE GO-AROUNDS; THE TCAS TFC WAS NEVER OBSERVED UNTIL THIS LAST OCCURRENCE; LEADING HIM TO BELIEVE THERE MAY BE A CONNECTION BTWN THE R/C ACFT AND THE TCAS 'RA'S'. THE RPTR DOESN'T RULE OUT A POSSIBLE PROB WITH HIS ACFT EQUIP; THE SAME ACFT WAS FLOWN DURING EACH 'RA'. SUPPLEMENTAL INFO: A 'TCAS' SPECIALIST ADVISES THAT THE R/C ACFT SHOULD NOT AFFECT TCAS OP; SUGGESTING THE PROB MAY LIE IN THE HAWKER 800'S 'TCAS SUPPRESSION BUSS.'