Narrative:

Airport was unusually busy with multiple aircraft landing on both parallel runways. I was instructed to hold west of airport for about 10 mins then told to enter downwind. After entering downwind; tower said to make a 360 degree left turn prior to re-entering downwind for right traffic for runway 19R. I was then told to follow a falcon on 4 mi final for runway 19R. As I looked for traffic; I saw an aircraft I thought was falcon so called tower with; 'falcon in sight.' when that aircraft passed beyond my 3 O'clock position; I began a turn right to base leg. As I made the turn; I looked toward runway 19R for falcon. When I didn't see it; I turned further right to avoid landing path. At about this time; tower called and asked if I turned inside falcon. I replied that I did and falcon called to say they had me in sight and were passing below me. I ended up landing behind falcon after resuming my approach. There was no mention of any incident but it was the closest I have ever come to another aircraft while landing. I now realize the aircraft I thought was 'my traffic' (falcon) was another aircraft on final for runway 19L. In future; in similar situation; I will ask tower to call my base turn.

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Original NASA ASRS Text

Title: A MOONEY 201 ON VISUAL APCH TO SNA TURNED IN TOO SOON AND EXPERIENCED A NEAR MISS WITH A HAWKER.

Narrative: ARPT WAS UNUSUALLY BUSY WITH MULTIPLE ACFT LNDG ON BOTH PARALLEL RWYS. I WAS INSTRUCTED TO HOLD W OF ARPT FOR ABOUT 10 MINS THEN TOLD TO ENTER DOWNWIND. AFTER ENTERING DOWNWIND; TWR SAID TO MAKE A 360 DEG L TURN PRIOR TO RE-ENTERING DOWNWIND FOR R TFC FOR RWY 19R. I WAS THEN TOLD TO FOLLOW A FALCON ON 4 MI FINAL FOR RWY 19R. AS I LOOKED FOR TFC; I SAW AN ACFT I THOUGHT WAS FALCON SO CALLED TWR WITH; 'FALCON IN SIGHT.' WHEN THAT ACFT PASSED BEYOND MY 3 O'CLOCK POS; I BEGAN A TURN R TO BASE LEG. AS I MADE THE TURN; I LOOKED TOWARD RWY 19R FOR FALCON. WHEN I DIDN'T SEE IT; I TURNED FURTHER R TO AVOID LNDG PATH. AT ABOUT THIS TIME; TWR CALLED AND ASKED IF I TURNED INSIDE FALCON. I REPLIED THAT I DID AND FALCON CALLED TO SAY THEY HAD ME IN SIGHT AND WERE PASSING BELOW ME. I ENDED UP LNDG BEHIND FALCON AFTER RESUMING MY APCH. THERE WAS NO MENTION OF ANY INCIDENT BUT IT WAS THE CLOSEST I HAVE EVER COME TO ANOTHER ACFT WHILE LNDG. I NOW REALIZE THE ACFT I THOUGHT WAS 'MY TFC' (FALCON) WAS ANOTHER ACFT ON FINAL FOR RWY 19L. IN FUTURE; IN SIMILAR SITUATION; I WILL ASK TWR TO CALL MY BASE TURN.

Data retrieved from NASA's ASRS site as of January 2009 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.