C182 PILOT ON RIGHT DOWNWIND IS CLEARED TO LAND ON RWY 17L AT APA BUT LINES UP FOR 17R; CAUSING NMAC WITH LOW WING ACFT LANDING 17R.

Narrative

I WAS TOLD BY ATC TO STAY W OF I-25 AND RPT MID-FIELD DOWNWIND; WHICH I DID. THIS APCH MAKES RWY 17R THE CLOSEST RWY. CTLR SAID HE WOULD CALL MY BASE LEG; WHICH HE DID; AND I WAS GIVEN CLRNC TO LAND RWY 17L. I TURNED BASE; GOT A VISUAL ON BOTH RWYS; AND TURNED FINAL FOR THE CLOSEST RWY. I EVEN CONFIRMED WITH THE CTLR THAT I WAS CLRED TO LAND RWY 17L WHICH HE CONFIRMED. I CONTINUED MY DSCNT. AT APPROX 300 FT AGL; A LOW WING ACFT APPEARED SLIGHTLY ABOVE AND IN FRONT OF ME. I NOTED TO TWR THAT I WAS ON THE WRONG RWY. TWR SAID I COULD SIDESTEP TO RWY 17L. THE OTHER PLANE INITIATED A GAR VEERING SLIGHTLY R. I STARTED A SHALLOW TURN TO THE L; ADDING PWR; BUT HIS PROP WASH CAUSED THE R WING TO LIFT UNEXPECTEDLY. I FOUGHT FOR POSITIVE CTL OF THE ACFT. I RE-ESTABLISHED A POSITIVE RATE OF CLB OVER RWY 17L. TWR STATED I COULD LAND RWY 28; WHICH I ELECTED TO DO. I FLY PRIMARILY TO SMALL; UNTWRED ARPTS SO I WAS ALSO VERY CONSCIOUS OF MY RADIO COM WITH THE TWR -- ALMOST TO THE POINT OF DISTR. I HAD LANDED EARLIER ON RWY 17R TO MEET MY FRIEND FOR LUNCH AND HIS FIRST SMALL PLANE EXPERIENCE. DURING OUR FLT; HE THOUGHT THAT LNDGS WOULD BE THE MOST FUN PART OF FLYING BECAUSE OF THE CHALLENGES. ON RETURNING TO THE ARPT TO DROP HIM OFF; I WAS UNCONSCIOUSLY EXPECTING TO USE THE RWY CLOSEST TO ME AND WAS CONCENTRATING ON MAKING A REALLY SMOOTH LNDG FOR MY FRIEND. LINING UP ON THE WRONG RWY WAS A TOTAL LAPSE OF SITUATIONAL AWARENESS AND COULD HAVE ENDED VERY BADLY. THERE WERE A NUMBER OF DISTRS BUT NO EXCUSES.