Date: 201512
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: Turbulence; 10
Light: Daylight
Aircraft: Cessna 170
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Personal
Flight phase: Landing
ATC / advisory: CTAF ZZZ
Reporter organization: Personal
Reporter function: Single Pilot
Reporter qualification: Flight Crew Private
Anomaly: Ground Event / Encounter Ground Strike - Aircraft; Inflight Event / Encounter Loss Of Aircraft Control; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: Aircraft Aircraft Damaged; Flight Crew Regained Aircraft Control
Contributing factors: Human Factors; Weather
Primary problem: Human Factors

Narrative: I was on a VFR flight plan; cruising at 7500 feet MSL. A cold front had passed through the night before; and the winds aloft were from the NW at about 15-20 kts. OAT was about 0 deg C. About 20 nm West; ATC flight following gave me the surface wind as 330@5G12; but noted that the information was about an hour old. ATC terminated flight following; and I began my descent and tuned in the ASOS to hear the winds were 320@7 kts; gusting to 15 kts. Hearing no traffic on the CTAF and seeing no other traffic; I decided to land on the most favorable runway; 35. I flew a close-in left downwind on 35 to visually check the wind sock and wind-t. They both verified that the wind was generally from the North-West; so I continued the left pattern to final for runway 35. A 2 mile final is recommended to avoid overflight of housing near the airport; so I had a long stable approach to touchdown.On final; I began a slight side slip to the left to counter the left crosswind I was experiencing (and that I had expected). I continued the slip until touchdown; where I performed a wheel landing. I had rolled for maybe 1 or 2 seconds on both mains; when I suddenly was hit by a gust from the left that initiated a veer to the left. I applied full right rudder and left aileron to counter; but my control inputs were not sufficient to get back to the centerline. I applied light brakes; but got off them when the nose dipped; and relied on rudder. As I neared the left edge of the runway; the right rudder input took effect and the aircraft began a right turn. Unfortunately; I had now over controlled and the aircraft continued into a tight right turn as the tail came around with the tailwheel now on the ground. I estimate my ground speed when the ground-loop started at about 30-40 mph. As the aircraft continued the right turn; the tail wheel unlocked and the turn tightened. The right wing lifted due to centripetal force from the turn and the wind (now out of the West) also picked it up enough so that the left wing tip drug on the runway over about a 10 to 15 foot arc. The aircraft ended up heading downwind on runway 35. After taxiing to the ramp and tying down; I observed the wind gusts shifting about 60 degrees from NNW to W periodically about every 5 minutes and then returning to NW after a about a minute. I observed 3 cycles of this gust behavior.

Callback: The reporter stated the left wing was damaged during the ground loop and will be repaired.



Synopsis: Cessna 170 pilot ground looped on landing in gusty wind conditions. The left wing was damaged when it dragged on the runway.