Narrative:

Engine failure [on] short final; engine died at low RPM setting. On the last landing; we were on final at about 400 feet landing on runway xx at ZZZ. Student gradually reduced power as we were a little high on the glideslope [and] engine started running roughly. I took controls; added power back in and the engine ran normally. Over the threshold in ground effect; the student pulled power to idle; at this point the engine sputtered and quit. I took controls as there was no go-around option; landed the aircraft and got off at the closest taxi way. I then looked around the cockpit; assured that the mixture was full rich; the fuel pump was on; the fuel selector was on the proper tank; and both magnetos were on. I then tried to restart the engine; the engine started but once again died shortly after I brought the throttle just below 1000 RPM. At this point; I switched tanks; retried the engine start checklist and got the same result. During the preflight inspection; I saw the student sump the fuel and confirmed there was no contaminants in the fuel; he then dumped the fuel in a slop tank. I also visually confirmed both tanks were full [and] the oil was within operating range. The oil was between 7.2-7.3 quarts; well within the operating range of 6-8 quarts. Nothing on the run up indicated of problems occurring in the flight.

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Original NASA ASRS Text

Title: PA-28 flight instructor reported an engine failure on short final.

Narrative: Engine failure [on] short final; engine died at low RPM setting. On the last landing; we were on final at about 400 feet landing on Runway XX at ZZZ. Student gradually reduced power as we were a little high on the glideslope [and] engine started running roughly. I took controls; added power back in and the engine ran normally. Over the threshold in ground effect; the student pulled power to idle; at this point the engine sputtered and quit. I took controls as there was no go-around option; landed the aircraft and got off at the closest taxi way. I then looked around the cockpit; assured that the mixture was full rich; the fuel pump was on; the fuel selector was on the proper tank; and both magnetos were on. I then tried to restart the engine; the engine started but once again died shortly after I brought the throttle just below 1000 RPM. At this point; I switched tanks; retried the Engine Start Checklist and got the same result. During the preflight inspection; I saw the student sump the fuel and confirmed there was no contaminants in the fuel; he then dumped the fuel in a slop tank. I also visually confirmed both tanks were full [and] the oil was within operating range. The oil was between 7.2-7.3 quarts; well within the operating range of 6-8 quarts. Nothing on the run up indicated of problems occurring in the flight.

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.