Narrative:

My student had just performed a landing. I brought the flap switch to the 'up' position and told my student to turn off the carburetor heat and add full power to take back off for a touch and go. The student added full power and we began to accelerate toward rotation speed. Approximately 5 mph before the published rotation speed; the airplane lurched into the air; which I thought was due to a gust of wind. I noticed immediately that the plane was flying very slowly and not climbing as it should. I looked out to the wing and noticed that the flaps had not retracted despite me moving the switch to the 'up' position. I immediately took the flight controls and told my student I was doing so. I tried to get the airplane to climb but could not get a climb without bleeding off the speed dangerously close to stall speed. At this point we were at around 200 AGL and approximately 1/4 mile from the end of the runway threshold. I could not stop the descent but had slowed it to approximately 50FPM while holding 60mph. I began to look in front of me for landing options. I spotted a small field at almost my 12 o'clock about a 1/2 mile away. I advised the local CTAF frequency that I had an emergency situation and was attempting to land in a field. I described the approximate location of the field so someone could find us. As I came over the tree line I leaned the mixture to full lean; switched the fuel selector to the 'off' position. After landing I immediately applied maximum brakes since we were quickly approaching a tree line. The plane went through mud and water which helped us slow to a stop approximately 150 feet in front of the tree line. I told my student to exit the airplane as I turned off the avionics master; battery master and removed the key. I then exited the airplane and waited for assistance. No one was harmed in the incident.

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Original NASA ASRS Text

Title: C172 instructor pilot reported landing in a field when the aircraft would not climb after the flaps failed to retract following a touch and go.

Narrative: My student had just performed a landing. I brought the flap switch to the 'UP' position and told my student to turn off the carburetor heat and add full power to take back off for a touch and go. The student added full power and we began to accelerate toward rotation speed. Approximately 5 mph before the published rotation speed; the airplane lurched into the air; which I thought was due to a gust of wind. I noticed immediately that the plane was flying very slowly and not climbing as it should. I looked out to the wing and noticed that the flaps had not retracted despite me moving the switch to the 'UP' position. I immediately took the flight controls and told my student I was doing so. I tried to get the airplane to climb but could not get a climb without bleeding off the speed dangerously close to stall speed. At this point we were at around 200 AGL and approximately 1/4 mile from the end of the runway threshold. I could not stop the descent but had slowed it to approximately 50FPM while holding 60mph. I began to look in front of me for landing options. I spotted a small field at almost my 12 o'clock about a 1/2 mile away. I advised the local CTAF frequency that I had an emergency situation and was attempting to land in a field. I described the approximate location of the field so someone could find us. As I came over the tree line I leaned the mixture to full lean; switched the fuel selector to the 'OFF' position. After landing I immediately applied maximum brakes since we were quickly approaching a tree line. The plane went through mud and water which helped us slow to a stop approximately 150 feet in front of the tree line. I told my student to exit the airplane as I turned off the avionics master; battery master and removed the key. I then exited the airplane and waited for assistance. No one was harmed in the incident.

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.