Mooney pilot reported returning to the departure airport due to a rough running engine.

Attributes
ACN	1554893
Time
Date	201806
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	M-20 Series Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	Takeoff
Route In Use	None
Flight Plan	VFR
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Private Flight Crew Instrument
Experience	Flight Crew Last 90 Days 50 Flight Crew Total 1800 Flight Crew Type 500
Events
Anomaly	Aircraft Equipment Problem Critical

Narrative:

On takeoff engine began to run rough and I told tower I was returning to [airport]. I turned crosswind; then downwind and landed without incident although I was 400 feet below pattern altitude because I reduced power and could not climb further. Complied with all clearances.

Original NASA ASRS Text

Title: Mooney pilot reported returning to the departure airport due to a rough running engine.

Narrative: On takeoff engine began to run rough and I told tower I was returning to [airport]. I turned crosswind; then downwind and landed without incident although I was 400 feet below pattern altitude because I reduced power and could not climb further. Complied with all clearances.

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.