Narrative:

I was just leveling off for cruise when we saw aircraft crossing from our right to left in our path. It was a low wing aircraft in a climb and when we saw it, it was at our 1 O'clock position within approximately 150' at approximately the same altitude. I banked sharply to the right and dove and the other aircraft an instant later banked to their right (away from us) and climbed. From their actions, I believe they did not see us until an instant after we started our bank to avoid them. I had just closed the cowl flaps and had looked up and outside when my passenger shouted at the same time that I saw them. We had been exercising extreme vigilance in our scanning for aircraft, and don't know what else we could have done. I had been doing shallow s-turns during the steeper part of our climb, but had already started leveling out, but had not completed it. We were indicating about 100 KTS airspeed. Possible contributing factors: both aircraft in a climb. At the point where I would have liked to have seen them a few mins earlier, we were both probably below the horizon. In the tahoe basin, there are many bright reflections from objects on the ground and on the lake. The lake also is very bright and reflective. In relation to these distracting reflections, we might not have been as obvious to each other. Also, the other aircraft was heading into the sun, which might have been why they didn't see us until we banked. We had our anticollision strobe operating. It is the bright, white type, not the red rotating beacon type. It is located on the belly of our aircraft. The high wing of our aircraft and low wing of their aircraft may have been a factor.

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Original NASA ASRS Text

Title: NMAC BETWEEN SMA AND SMA, ONE LEVEL, ONE CLIMBING.

Narrative: I WAS JUST LEVELING OFF FOR CRUISE WHEN WE SAW ACFT XING FROM OUR RIGHT TO LEFT IN OUR PATH. IT WAS A LOW WING ACFT IN A CLB AND WHEN WE SAW IT, IT WAS AT OUR 1 O'CLOCK POS WITHIN APPROX 150' AT APPROX THE SAME ALT. I BANKED SHARPLY TO THE RIGHT AND DOVE AND THE OTHER ACFT AN INSTANT LATER BANKED TO THEIR RIGHT (AWAY FROM US) AND CLBED. FROM THEIR ACTIONS, I BELIEVE THEY DID NOT SEE US UNTIL AN INSTANT AFTER WE STARTED OUR BANK TO AVOID THEM. I HAD JUST CLOSED THE COWL FLAPS AND HAD LOOKED UP AND OUTSIDE WHEN MY PAX SHOUTED AT THE SAME TIME THAT I SAW THEM. WE HAD BEEN EXERCISING EXTREME VIGILANCE IN OUR SCANNING FOR ACFT, AND DON'T KNOW WHAT ELSE WE COULD HAVE DONE. I HAD BEEN DOING SHALLOW S-TURNS DURING THE STEEPER PART OF OUR CLB, BUT HAD ALREADY STARTED LEVELING OUT, BUT HAD NOT COMPLETED IT. WE WERE INDICATING ABOUT 100 KTS AIRSPD. POSSIBLE CONTRIBUTING FACTORS: BOTH ACFT IN A CLB. AT THE POINT WHERE I WOULD HAVE LIKED TO HAVE SEEN THEM A FEW MINS EARLIER, WE WERE BOTH PROBABLY BELOW THE HORIZON. IN THE TAHOE BASIN, THERE ARE MANY BRIGHT REFLECTIONS FROM OBJECTS ON THE GND AND ON THE LAKE. THE LAKE ALSO IS VERY BRIGHT AND REFLECTIVE. IN RELATION TO THESE DISTRACTING REFLECTIONS, WE MIGHT NOT HAVE BEEN AS OBVIOUS TO EACH OTHER. ALSO, THE OTHER ACFT WAS HDG INTO THE SUN, WHICH MIGHT HAVE BEEN WHY THEY DIDN'T SEE US UNTIL WE BANKED. WE HAD OUR ANTICOLLISION STROBE OPERATING. IT IS THE BRIGHT, WHITE TYPE, NOT THE RED ROTATING BEACON TYPE. IT IS LOCATED ON THE BELLY OF OUR ACFT. THE HIGH WING OF OUR ACFT AND LOW WING OF THEIR ACFT MAY HAVE BEEN A FACTOR.

Data retrieved from NASA's ASRS site as of August 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.