Narrative:

We took off runway xx to practice some night takeoffs and landings. Upon the second takeoff somewhere around 600-700 ft the rpm dropped drastically then the engine power dropped and we could not climb. Almost simultaneously I took control from my student because I could hear stall warning and the airplane was getting uncontrollable [quickly] so I pitched down [advised ATC] and landed on runway yy (opposite direction of the runway we took off from) with a tailwind. Just about 15 ft I could hear the engine rev up again.

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Original NASA ASRS Text

Title: C-152 instructor pilot reported power loss during initial climb that resulted in a return to the departure airport.

Narrative: We took off Runway XX to practice some night takeoffs and landings. Upon the second takeoff somewhere around 600-700 ft the rpm dropped drastically then the engine power dropped and we could not climb. Almost simultaneously I took control from my student because I could hear stall warning and the airplane was getting uncontrollable [quickly] so I pitched down [advised ATC] and landed on Runway YY (opposite direction of the runway we took off from) with a tailwind. Just about 15 ft I could hear the engine rev up again.

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.