Narrative:

During climb on a glider tow I was making a slow climbing left turn. I came close to a glider in the same thermal I was attempting to climb in which was above and to the left of me during and before the encounter. I did not spot this aircraft earlier, possibly because the top of the canopy shade obstructed my view above in the turn. At the last min I leveled out to avoid the possible contact. There were 1 to 2 other gliders in the same location which I did have visual contact on. This also possibly distracted me from visual contact with the #2 aircraft. Suggested solutions for this problem include better visual scanning, possibly avoiding traffic conflicts by segregating tow climb areas from other gliders in lift areas and eliminating visual blind spots in the tow planes where possible.

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Original NASA ASRS Text

Title: A TOW PLT EXPERIENCED AN NMAC WHILE TOWING A GLIDER IN A THERMAL. POTENTIAL CONFLICT. NMAC.

Narrative: DURING CLB ON A GLIDER TOW I WAS MAKING A SLOW CLBING L TURN. I CAME CLOSE TO A GLIDER IN THE SAME THERMAL I WAS ATTEMPTING TO CLB IN WHICH WAS ABOVE AND TO THE L OF ME DURING AND BEFORE THE ENCOUNTER. I DID NOT SPOT THIS ACFT EARLIER, POSSIBLY BECAUSE THE TOP OF THE CANOPY SHADE OBSTRUCTED MY VIEW ABOVE IN THE TURN. AT THE LAST MIN I LEVELED OUT TO AVOID THE POSSIBLE CONTACT. THERE WERE 1 TO 2 OTHER GLIDERS IN THE SAME LOCATION WHICH I DID HAVE VISUAL CONTACT ON. THIS ALSO POSSIBLY DISTRACTED ME FROM VISUAL CONTACT WITH THE #2 ACFT. SUGGESTED SOLUTIONS FOR THIS PROB INCLUDE BETTER VISUAL SCANNING, POSSIBLY AVOIDING TFC CONFLICTS BY SEGREGATING TOW CLB AREAS FROM OTHER GLIDERS IN LIFT AREAS AND ELIMINATING VISUAL BLIND SPOTS IN THE TOW PLANES WHERE POSSIBLE.

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.