Narrative:

[Instructor] was teaching pre-solo landing training and the student was on glide path and entered the round out and flare and was correctly performed. Normal sink to landing stall horn sounded just as we touched the runway centerline the plane abruptly veered to the grass leaving no time for go around. I immediately took control of aircraft and applied brakes as we entered the grass. We encroached the grass approximately 20 to 40 ft. I determined that the we had not hit anything and the engine was at idle and I turned the plane back to re-enter the runway to taxi back to the FBO to inspect if there was damage. Upon inspection of prop; airframe I determined that only damage was a flat on the left tire. I called [chief pilot] to discuss the incident and I determined that a safe flight back to [our departure airport] was the best course of action. After discussing with maintenance a general assumption was made that we believe the student pilot had applied left brake prior to landing causing the flat spot on the tire.

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Original NASA ASRS Text

Title: Cessna 172 Flight Instructor reported the student ran off the runway while landing.

Narrative: [Instructor] was teaching pre-solo landing training and the student was on glide path and entered the round out and flare and was correctly performed. Normal sink to landing stall horn sounded just as we touched the runway centerline the plane abruptly veered to the grass leaving no time for go around. I immediately took control of aircraft and applied brakes as we entered the grass. We encroached the grass approximately 20 to 40 ft. I determined that the we had not hit anything and the engine was at idle and I turned the plane back to re-enter the runway to taxi back to the FBO to inspect if there was damage. Upon inspection of prop; airframe I determined that only damage was a flat on the left tire. I called [Chief Pilot] to discuss the incident and I determined that a safe flight back to [our departure airport] was the best course of action. After discussing with Maintenance a general assumption was made that we believe the student pilot had applied left brake prior to landing causing the flat spot on the tire.

Data retrieved from NASA's ASRS site 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.