Narrative:

VFR low level flight (less than 2000 AGL) from sequin, tx, to burnet, tx, remaining clear of aus arsa using pilotage only (sat sectional). Monitoring aus departure frequency (119.0 MHZ) from approximately wsw aus to approximately overhead T88 airport (approximately 3 mins before incident). Moments after crossing over T88 (where I was looking for aircraft below me in the pattern), I looked up briefly from sectional to attempt to identify my exact position by comparing lake travis contours to those on sectional. At this point, I saw a flash of beige in my left eye's peripheral vision. Object was below and slightly left of me. I did not have time to react before it disappeared below and behind my aircraft. Looking back and right of my aircraft, I saw a beige small aircraft Y in a slight climbing left turn. Small aircraft Y's direction of flight was approximately ese at the time. I was excessively concerned with determining my exact position over the ground at all times, thus keeping my eyes 'in' the cockpit looking at sectional too much. I also relied on the belief that I was too low to interfere with traffic on V76 between aus and llo (I calculated my altitude was 1570 ft AGL at the time of incident). I further relied on belief that there was no other traffic near me because I had not heard aus TRACON call my target as traffic to anybody for approximately 15-20 mins prior to incident. The thought that another aircraft might not be talking to aus either did not occur to me. I assume small aircraft Y was not on the airway proper, but rather doing low sightseeing over the lake. I am glad that he looked out when he did. In future, I will be less concerned with exact position awareness, and more concerned with looking for conflicting traffic. I will also use flight following when in vicinity of major airports.

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Original NASA ASRS Text

Title: 2 SMAS HAD AN NMAC NEAR A MAJOR ARPT.

Narrative: VFR LOW LEVEL FLT (LESS THAN 2000 AGL) FROM SEQUIN, TX, TO BURNET, TX, REMAINING CLR OF AUS ARSA USING PILOTAGE ONLY (SAT SECTIONAL). MONITORING AUS DEP FREQ (119.0 MHZ) FROM APPROX WSW AUS TO APPROX OVERHEAD T88 ARPT (APPROX 3 MINS BEFORE INCIDENT). MOMENTS AFTER XING OVER T88 (WHERE I WAS LOOKING FOR ACFT BELOW ME IN THE PATTERN), I LOOKED UP BRIEFLY FROM SECTIONAL TO ATTEMPT TO IDENT MY EXACT POS BY COMPARING LAKE TRAVIS CONTOURS TO THOSE ON SECTIONAL. AT THIS POINT, I SAW A FLASH OF BEIGE IN MY L EYE'S PERIPHERAL VISION. OBJECT WAS BELOW AND SLIGHTLY L OF ME. I DID NOT HAVE TIME TO REACT BEFORE IT DISAPPEARED BELOW AND BEHIND MY ACFT. LOOKING BACK AND R OF MY ACFT, I SAW A BEIGE SMA Y IN A SLIGHT CLBING L TURN. SMA Y'S DIRECTION OF FLT WAS APPROX ESE AT THE TIME. I WAS EXCESSIVELY CONCERNED WITH DETERMINING MY EXACT POS OVER THE GND AT ALL TIMES, THUS KEEPING MY EYES 'IN' THE COCKPIT LOOKING AT SECTIONAL TOO MUCH. I ALSO RELIED ON THE BELIEF THAT I WAS TOO LOW TO INTERFERE WITH TFC ON V76 BTWN AUS AND LLO (I CALCULATED MY ALT WAS 1570 FT AGL AT THE TIME OF INCIDENT). I FURTHER RELIED ON BELIEF THAT THERE WAS NO OTHER TFC NEAR ME BECAUSE I HAD NOT HEARD AUS TRACON CALL MY TARGET AS TFC TO ANYBODY FOR APPROX 15-20 MINS PRIOR TO INCIDENT. THE THOUGHT THAT ANOTHER ACFT MIGHT NOT BE TALKING TO AUS EITHER DID NOT OCCUR TO ME. I ASSUME SMA Y WAS NOT ON THE AIRWAY PROPER, BUT RATHER DOING LOW SIGHTSEEING OVER THE LAKE. I AM GLAD THAT HE LOOKED OUT WHEN HE DID. IN FUTURE, I WILL BE LESS CONCERNED WITH EXACT POS AWARENESS, AND MORE CONCERNED WITH LOOKING FOR CONFLICTING TFC. I WILL ALSO USE FLT FOLLOWING WHEN IN VICINITY OF MAJOR ARPTS.

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.