Narrative:

I caused an near midair collision at a grass strip glider operation with occasional GA traffic. Normal operation is tow out on runway 18 and land runway 36 to minimize occupied runway time. Wind was 6-8 kt from ~ 330; broken cirrus skies with bases ~ 4000 AGL. I was unaware that glider 1 was on left base or final for runway 36 while the PA25 (me) and glider 2 began departure roll on runway 18. When the PA25 became airborne glider 1 became visible and appeared to be at approximately 50' to 80' fully committed. Both PA25 and glider 1 altered course to increase separation. Rate of closure was ~ 100 mph and the estimated 1450 feet remaining between the two aircraft would have been consume in less than 9.8 seconds had altered courses had not been initiated.I towed glider 1 to 3000' AGL; returned; refueled; and taxied into position to connect to glider 2. Glider 1 released northwest of the field. The PA25 was angled at 45 degrees to the active to minimize prop wash on the glider; maximize view of downwind; and complete checklist. Wing runner ran to tell me of glider 2 intentions as radio was inoperative. I picked up an announcement from glider 1 and simultaneously removed one headset to hear wing runner. I assumed from the partial that glider 1 was at the north ip in lift; our standard announcement prior to entering downwind. I looked thoroughly toward the northwest for glider 1; did not see it and proceeded to take up slack rope. PA25 received standard soaring society of america take off signals from wing runner and glider 2 PIC. Returned rudder waggle and departed runway 18 announcing we were rolling on 18. The PA25 became airborne and glider 1 became visible on final for runway 36.critical misses: the announcement from glider 1 was a partial - he announced downwind not at the ip. Wing runner waited until slack was taken up to clear the area. I cleared the northern quadrant not knowing that glider 1 was in the southern quadrant. I convinced myself of a false position for glider 1 I failed to confirm glider 1 position & intentions via radio. Avoidance action: I initiated a left turn toward the alternate runway. Glider 1 altered course slightly toward left side of runway 36. Glider 2 followed me and released west of the field. Lessons learned: avoid letting distractions disrupt the safe routine. Make confirmations - not assumptions clear the area all the time - not just prior to departure. One announcement may be missed - additional announcements don't cost anything. Announce position more often. Take inventory - know which aircraft are in the air. Our safety training was invaluable and both pilots reacted promptly with correct decisions and reactions.

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Original NASA ASRS Text

Title: PA25 tow pilot with glider in tow reports NMAC with another glider at 50 feet landing opposite direction.

Narrative: I caused an NMAC at a grass strip glider operation with occasional GA traffic. Normal operation is tow out on Runway 18 and land Runway 36 to minimize occupied runway time. Wind was 6-8 kt from ~ 330; broken cirrus skies with bases ~ 4000 AGL. I was unaware that Glider 1 was on left base or final for Runway 36 while the PA25 (me) and Glider 2 began departure roll on Runway 18. When the PA25 became airborne Glider 1 became visible and appeared to be at approximately 50' to 80' fully committed. Both PA25 and Glider 1 altered course to increase separation. Rate of closure was ~ 100 mph and the estimated 1450 feet remaining between the two aircraft would have been consume in less than 9.8 seconds had altered courses had not been initiated.I towed Glider 1 to 3000' AGL; returned; refueled; and taxied into position to connect to Glider 2. Glider 1 released northwest of the field. The PA25 was angled at 45 degrees to the active to minimize prop wash on the glider; maximize view of downwind; and complete checklist. Wing runner ran to tell me of Glider 2 intentions as radio was INOP. I picked up an announcement from Glider 1 and simultaneously removed one headset to hear wing runner. I assumed from the partial that Glider 1 was at the north IP in lift; our standard announcement prior to entering downwind. I looked thoroughly toward the northwest for Glider 1; did not see it and proceeded to take up slack rope. PA25 received standard Soaring Society of America take off signals from wing runner and Glider 2 PIC. Returned rudder waggle and departed Runway 18 announcing we were rolling on 18. The PA25 became airborne and Glider 1 became visible on final for Runway 36.Critical misses: The announcement from Glider 1 was a partial - he announced downwind not at the IP. Wing runner waited until slack was taken up to clear the area. I cleared the northern quadrant not knowing that Glider 1 was in the southern quadrant. I convinced myself of a false position for Glider 1 I failed to confirm Glider 1 position & intentions via radio. Avoidance action: I initiated a left turn toward the alternate runway. Glider 1 altered course slightly toward left side of Runway 36. Glider 2 followed me and released west of the field. Lessons Learned: Avoid letting distractions disrupt the safe routine. Make confirmations - not assumptions clear the area all the time - not just prior to departure. One announcement may be missed - additional announcements don't cost anything. Announce position more often. Take inventory - know which aircraft are in the air. Our safety training was invaluable and both pilots reacted promptly with correct decisions and reactions.

Data retrieved from NASA's ASRS site as of April 2012 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.