Incident Overview
During a dual primary cross-country flight, a student pilot was executing an approach and landing at Prescott. The certified flight instructor (CFI) reported that the approach and touchdown proceeded normally. However, as the aircraft slowed, it began a gradual drift to the right. The student's attempts to correct the right turn with control inputs were unsuccessful, and the aircraft subsequently ground looped in soft soil off the right side of the runway.
CFI Comments
The CFI stated that he "probably waited too long to take the aircraft" from the student, whom he described as "an excellent student." The CFI's logbook revealed that he had approximately 150 hours of experience as a CFI at the time of the incident.
Mechanical Findings
Following the event, a repair station examined the aircraft. The inspection disclosed that the tailwheel steering pawl was broken. The pawl's condition allowed the tailwheel to steer only to the right; engagement leftward was not possible.
Pilot Experience
The student pilot's entire flight time had been accrued in Cessna 120 and 180 model aircraft. No other aircraft types were mentioned in the student's logged experience.
Conclusion
The combination of a mechanical failure—specifically the broken tailwheel steering pawl that prevented left steering—and the timing of the CFI's intervention contributed to the ground loop. The aircraft departed the runway surface and came to rest in the soft soil alongside the runway.