Incident
The aircraft began to wander back and forth across the runway during the takeoff roll. As it veered to the left, the certified flight instructor (CFI) took control. The left wheel then struck a snowbank, and the aircraft ground looped to the left, substantially damaging the right wing before coming to rest. A 10-degree left crosswind was present at the time.
Instructor Experience
The CFI was inexperienced as an instructor and had logged only 26 hours of flight time in a PA22 aircraft.
Aircraft Modification
The aircraft had been modified by the removal of its nose wheel and the installation of a tailwheel. However, a new type certificate had not been issued for this modification.