Narrative:

I was out practicing normal landings with my student. We took off and were on 21L and then were switched to 21R halfway through the flight. We were dealing with a quartering crosswind most of the flight and it was getting gusty. Report was 169 true 14 gusting to 19. Wind was varying quite a bit. Right after the incident my student checked and it was gusting 21. We had to change our crosswind corrections continuously. On this last pass we touched down lightly and kept the nose off the ground. My student then took off the flaps and then I felt acceleration and thought he had started the go. We cocked quickly to the left as a gust hit us. I reached down to pull the throttle out and it was out; while pushing rudder to get the nose straight. We rolled off the runway and down a hill. Trying to avoid rocks and bushes we maneuvered to get the plane stopped. The speed with which we ran down the hill allowed us to hop over the ditch. We came to a stop about a hundred yards into the grass and let tower know what had happened. They radioed the trucks for help. I checked all the plane gauges and all looked well. We asked the tower if they wanted us to shut down; which they replied yes. We shut down the plane and checked it out. All looked fine. The fire trucks arrived and we were asked if we were alright. We then talked with the airport operation employee and wrote up a simple report of the facts. We were waiting to move the plane. After maintenance towed the plane up the hill we taxied it back and noticed no problems with the plane. Throttle seemed to be fine with no changes.

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Original NASA ASRS Text

Title: A C-172 instructor reported he and his student; the flying pilot; landed in gusty conditions and departed the runway after a 21 knot gust turned the aircraft but no damage was found after the aircraft was towed back to the runway.

Narrative: I was out practicing normal landings with my student. We took off and were on 21L and then were switched to 21R halfway through the flight. We were dealing with a quartering crosswind most of the flight and it was getting gusty. Report was 169 true 14 gusting to 19. Wind was varying quite a bit. Right after the incident my student checked and it was gusting 21. We had to change our crosswind corrections continuously. On this last pass we touched down lightly and kept the nose off the ground. My student then took off the flaps and then I felt acceleration and thought he had started the go. We cocked quickly to the left as a gust hit us. I reached down to pull the throttle out and it was out; while pushing rudder to get the nose straight. We rolled off the runway and down a hill. Trying to avoid rocks and bushes we maneuvered to get the plane stopped. The speed with which we ran down the hill allowed us to hop over the ditch. We came to a stop about a hundred yards into the grass and let Tower know what had happened. They radioed the trucks for help. I checked all the plane gauges and all looked well. We asked the Tower if they wanted us to shut down; which they replied yes. We shut down the plane and checked it out. All looked fine. The fire trucks arrived and we were asked if we were alright. We then talked with the airport operation employee and wrote up a simple report of the facts. We were waiting to move the plane. After Maintenance towed the plane up the hill we taxied it back and noticed no problems with the plane. Throttle seemed to be fine with no changes.

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.