Narrative:

The incident occurred during a training flight on the final leg of our approach to landing. My student was manipulating the controls. He is currently fine tuning his landings. We were a little high and a little fast. I told him to bring the throttle to idle to return to glide path and pitch for final speed. He complied. As we continue the descent; we were on glide path and still a little fast. As we transitioned into the flare it became obvious that we were not going to be able to touchdown and bring the airplane to a stop before the end of the runway. I was concerned that if at that point we executed a go-around that we would hit the trees on the departure end of the runway. I decided to continue with the landing with the potential to overrun the runway instead of attempting the go-around. I immediately took the flight controls from my student and forced the plane on the ground and applied maximum braking. The plane came to a stop in the mud just past the end of the runway. We exited the aircraft then removed it from the mud and inspected for damage. The plane and its occupants were uninjured.

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Original NASA ASRS Text

Title: C172 flight instructor reported an unstabilized approach by the student pilot led to a runway excursion.

Narrative: The incident occurred during a training flight on the final leg of our approach to landing. My student was manipulating the controls. He is currently fine tuning his landings. We were a little high and a little fast. I told him to bring the throttle to idle to return to glide path and pitch for final speed. He complied. As we continue the descent; we were on glide path and still a little fast. As we transitioned into the flare it became obvious that we were not going to be able to touchdown and bring the airplane to a stop before the end of the runway. I was concerned that if at that point we executed a go-around that we would hit the trees on the departure end of the runway. I decided to continue with the landing with the potential to overrun the runway instead of attempting the go-around. I immediately took the flight controls from my student and forced the plane on the ground and applied maximum braking. The plane came to a stop in the mud just past the end of the runway. We exited the aircraft then removed it from the mud and inspected for damage. The plane and its occupants were uninjured.

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.