Narrative:

I was pilot in command of the carbon cub. Another pilot was in the front seat at the controls. We had departed approximately 30 minutes earlier and spent time at the practice area. We then got the ATIS and returned to the airport for touch and go's.I had spent 15 hours in this cub the preceding week; instructing the owner who is nearing solo. I wanted an opinion on how the cub felt to another pilot; hoping it might help me to better help the owner. I had the other pilot make a normal approach; full flaps. After a good landing with a normal touchdown he commented 'it's skittish all right' and at that moment the airplane entered a ground loop. I took control and we stopped on the runway after the unwanted excursion. I taxied the airplane clear of the runway and called for an aircraft tug to come and assist. The operations trucks responded; inspected the runway and retrieved parts of the right brake assembly. After 50 plus years of operating tail-draggers; a dose of humility was probably overdue.

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Original NASA ASRS Text

Title: Two pilots aboard a 'Carbon Cub' LSA suffered a ground loop after landing during which parts of the right gear brake assembly separated from the aircraft.

Narrative: I was pilot in command of the Carbon Cub. Another pilot was in the front seat at the controls. We had departed approximately 30 minutes earlier and spent time at the practice area. We then got the ATIS and returned to the airport for touch and go's.I had spent 15 hours in this Cub the preceding week; instructing the owner who is nearing solo. I wanted an opinion on how the Cub felt to another pilot; hoping it might help me to better help the owner. I had the other pilot make a normal approach; full flaps. After a good landing with a normal touchdown he commented 'It's skittish all right' and at that moment the airplane entered a ground loop. I took control and we stopped on the runway after the unwanted excursion. I taxied the airplane clear of the runway and called for an aircraft tug to come and assist. The operations trucks responded; inspected the runway and retrieved parts of the right brake assembly. After 50 plus years of operating tail-draggers; a dose of humility was probably overdue.

Data retrieved from NASA's ASRS site as of July 2013 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.