Narrative:

I transferred ownership of an ultralight in 2013 but the new owner failed to come and get the small single seat aircraft. Fearing that the upcoming winter would damage the airframe; I contacted the new owner and offered to get the plane running and fly it to the new owner's location. The carb had clogged and the spark system had failed in the 2 years that the plane sat out of use. After a couple months of work the engine started and I began some taxi tests. I started to taxi on the runway with takeoff at the time a possible option; I tried to gain speed first. I erred by not holding the stick forward and pulled back on the stick to a neutral position; at which point the tailwheel contacted the pavement the plane began a violent side to side motion and the tailwheel broke causing a ground loop to the left and the front of the aircraft came in contact with the glide slope indicator light; the light shearing off from its' moorings and ended up on the ground. A tenant at the airport came out with his pickup truck and we towed the aircraft back to its parking spot. I have started with repairs but presently do not have enough money to cover a new tailwheel and a new prop. Having not flown the ultralight for 2 years I should have built up speed more gradually and the best way to control the defective tailwheel would have been to hold it off the ground.

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Original NASA ASRS Text

Title: Ultralight pilot reported losing control of his aircraft during high speed taxi tests. An apparently defective tail wheel is allowed to contact the runway resulting in a ground loop and damage to the aircraft.

Narrative: I transferred ownership of an ultralight in 2013 but the new owner failed to come and get the small single seat aircraft. Fearing that the upcoming winter would damage the airframe; I contacted the new owner and offered to get the plane running and fly it to the new owner's location. The carb had clogged and the spark system had failed in the 2 years that the plane sat out of use. After a couple months of work the engine started and I began some taxi tests. I started to taxi on the runway with takeoff at the time a possible option; I tried to gain speed first. I erred by not holding the stick forward and pulled back on the stick to a neutral position; at which point the tailwheel contacted the pavement the plane began a violent side to side motion and the tailwheel broke causing a ground loop to the left and the front of the aircraft came in contact with the glide slope indicator light; the light shearing off from its' moorings and ended up on the ground. A tenant at the airport came out with his pickup truck and we towed the aircraft back to its parking spot. I have started with repairs but presently do not have enough money to cover a new tailwheel and a new prop. Having not flown the ultralight for 2 years I should have built up speed more gradually and the best way to control the defective tailwheel would have been to hold it off the ground.

Data retrieved from NASA's ASRS site 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.