Narrative:

Final landing of the flight was to be made with [pilot receiving instruction] flying the aircraft; previous approach to same runway resulted in a go-around due to low airspeed; and high flare. During approach to the incident landing pilot was at a better altitude however slow on airspeed. Pilot touched down at the stall horn; and immediately pulled the control back over rotating; resulting in an audible scrapping sound with aircraft on the runway center line in a nose up attitude. During the entire approach my hands were in a defensive position; right hand open in my lap ready to catch the yoke coming back; left hand resting on my knee to catch the yoke going forward. Pilot's rotation was quicker than expected; resulting in the tail striking the ground before I was able to catch the yoke.I believe there is little I could have done to prevent this incident from occurring. A stabilized approach to landing should have been required; or go-around executed. At no time did I believe that the landing was unsafe; and being a training flight (last lesson before stage 1 check) I felt it necessary for the student to see how the resultant landing would be or make the decision on their own to execute a go-around.

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Original NASA ASRS Text

Title: C172 flight instructor reported a ground strike due to an unstabilized approach by the pilot flying.

Narrative: Final landing of the flight was to be made with [pilot receiving instruction] flying the aircraft; previous approach to same runway resulted in a go-around due to low airspeed; and high flare. During approach to the incident landing pilot was at a better altitude however slow on airspeed. Pilot touched down at the stall horn; and immediately pulled the control back over rotating; resulting in an audible scrapping sound with aircraft on the runway center line in a nose up attitude. During the entire approach my hands were in a defensive position; right hand open in my lap ready to catch the yoke coming back; left hand resting on my knee to catch the yoke going forward. Pilot's rotation was quicker than expected; resulting in the tail striking the ground before I was able to catch the yoke.I believe there is little I could have done to prevent this incident from occurring. A stabilized approach to landing should have been required; or go-around executed. At no time did I believe that the landing was unsafe; and being a training flight (last lesson before stage 1 check) I felt it necessary for the student to see how the resultant landing would be or make the decision on their own to execute a go-around.

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.