Narrative:

Arriving bur from the northwest (gmn from VOR). Conditions : usual thick haze/smoke and heavy traffic in arsa/air traffic area. Instructed to 'turn final for runway 15 at or above 3000''. Within 3 mi, tower instructed '#2 following aircraft on base for runway 15, enter base for runway 15' (implicit right base). Could not spot traffic in haze, informed tower, and asked them to call my left turn to right base for runway 15. Very busy scanning for traffic in haze, trying not to lose sight of airport, looking for whiteman air traffic area traffic, wondering how I will be able to dive-bomb from 3000' (2300 AGL) so close to the airport, talking on radio, and prelndg checklist. At this point my 4 yr old passenger in the back seat lets out a blood curdling scream into the intercom and starts crying. He had bit his lip, hard. A min later, tower responds with 'enter left base runway 7'. With all the confusion/distraction, I zeroed in on the word 'left', and began my expected left turn putting me on right base runway 15. Tower asks 'confirm entering left base runway 7'. Admitted the mixup and continued the turn full 360 degree (to stay away from runway 15 traffic) to enter left base 7. Contributing factors: expectation, wanting the left turn called and seemingly 'getting it'. This was made worse by not reading back the entire instruction. I only answered the tower instruction 'enter left base runway 7, #2 following medium large transport on final' with 'looking for traffic'. I spotted an medium large transport on final runway 7 immediately (no factor), but began looking for the #1 medium large transport on final for runway 15, where I thought they wanted me. If I had read back all the instruction, it may have occurred to me or the tower the impending miscue. I was not thinking 100%.

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Original NASA ASRS Text

Title: GA SMA TRACK HEADING DEVIATION ENTERING BUR ATA.

Narrative: ARRIVING BUR FROM THE NW (GMN FROM VOR). CONDITIONS : USUAL THICK HAZE/SMOKE AND HEAVY TFC IN ARSA/ATA. INSTRUCTED TO 'TURN FINAL FOR RWY 15 AT OR ABOVE 3000''. WITHIN 3 MI, TWR INSTRUCTED '#2 FOLLOWING ACFT ON BASE FOR RWY 15, ENTER BASE FOR RWY 15' (IMPLICIT R BASE). COULD NOT SPOT TFC IN HAZE, INFORMED TWR, AND ASKED THEM TO CALL MY L TURN TO R BASE FOR RWY 15. VERY BUSY SCANNING FOR TFC IN HAZE, TRYING NOT TO LOSE SIGHT OF ARPT, LOOKING FOR WHITEMAN ATA TFC, WONDERING HOW I WILL BE ABLE TO DIVE-BOMB FROM 3000' (2300 AGL) SO CLOSE TO THE ARPT, TALKING ON RADIO, AND PRELNDG CHKLIST. AT THIS POINT MY 4 YR OLD PAX IN THE BACK SEAT LETS OUT A BLOOD CURDLING SCREAM INTO THE INTERCOM AND STARTS CRYING. HE HAD BIT HIS LIP, HARD. A MIN LATER, TWR RESPONDS WITH 'ENTER L BASE RWY 7'. WITH ALL THE CONFUSION/DISTR, I ZEROED IN ON THE WORD 'LEFT', AND BEGAN MY EXPECTED L TURN PUTTING ME ON R BASE RWY 15. TWR ASKS 'CONFIRM ENTERING L BASE RWY 7'. ADMITTED THE MIXUP AND CONTINUED THE TURN FULL 360 DEG (TO STAY AWAY FROM RWY 15 TFC) TO ENTER L BASE 7. CONTRIBUTING FACTORS: EXPECTATION, WANTING THE L TURN CALLED AND SEEMINGLY 'GETTING IT'. THIS WAS MADE WORSE BY NOT READING BACK THE ENTIRE INSTRUCTION. I ONLY ANSWERED THE TWR INSTRUCTION 'ENTER L BASE RWY 7, #2 FOLLOWING MLG ON FINAL' WITH 'LOOKING FOR TFC'. I SPOTTED AN MLG ON FINAL RWY 7 IMMEDIATELY (NO FACTOR), BUT BEGAN LOOKING FOR THE #1 MLG ON FINAL FOR RWY 15, WHERE I THOUGHT THEY WANTED ME. IF I HAD READ BACK ALL THE INSTRUCTION, IT MAY HAVE OCCURRED TO ME OR THE TWR THE IMPENDING MISCUE. I WAS NOT THINKING 100%.

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.