The Cessna 185 (C185) aircraft had returned and landed at the departure aerodrome after completing a charter flight of approximately 90 minutes duration. The pilot reported that following a normal landing and after the tail wheel had been lowered to the runway, the aircraft nose commenced to yaw to the right. The pilot estimated that the aircraft was travelling at about 20 kts and despite applying full rudder and the use of differential braking it was not possible to regain directional control and the aircraft ground-looped. The left main gear-leg collapsed and the outboard portion of the left wing was substantially damaged when it struck the surface of the runway. The propeller also was damaged on contact with the runway. The pilot and three passengers were not injured and vacated the aircraft without assistance.
The pilot had been endorsed on the aircraft approximately one week before the accident. Although he had significant experience operating other tail-wheel equipped aircraft, he had logged only 18 hours on the C185. The majority of that experience had been accumulated while ferrying the aircraft from Moorabbin to Broome.
Following the accident, archived data from the Broome automatic weather station was retrieved from the Bureau of Meteorology. The data indicated that at the time of the accident a southerly wind was blowing with wind gusts recorded up to 11 kts. Analysis of the data indicated that the pilot could have encountered a right crosswind of up to 10 kts during the landing. That was within the aircraft manufacturer's demonstrated crosswind limit of 15 kts.
The aircraft centre of gravity was calculated to have been within published limits. However, it was close to the aft limit, thereby making directional control more difficult in the gusting crosswind conditions.
The weather conditions prevailing at the time of the accident would have made the aircraft more difficult to control, especially during the later stages of the landing roll as the aircraft slowed down and the rudder became less effective. Directional control at lower speeds becomes increasingly dependent on tail-wheel steering and the use of differential braking. The directional instability would have been further exacerbated with any sudden increase in crosswind component due to the gusty crosswind conditions.