Narrative:

I was practicing my pattern work and takeoffs and landing staying in the traffic pattern of dxr. At about 400' AGL, 850' MSL my engine started to wake a very loud noise and run rough. I was too high to land straight ahead. I continued to climb and contacted dxr tower to tell them that my engine is running rough and I would like to land as soon as possible. They offer me runway 35-17 but upon attaining pattern altitude I requested the active runway 26-8 which did not have a crosswind. The tower asked if I needed fire equipment which I stated, 'not yet.' the tower cleared me to land on runway 26 and held other traffic. I made a short approach and landed west/O incident, cleared the runway and was cleared to taxi back to my FBO. I had the aircraft repaired. The exhaust pipe on #4 cylinder had fallen off causing the noise and rough engine.

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Original NASA ASRS Text

Title: GA SMA ON A TRAINING FLT DEVELOPED ENGINE PROBLEM AFTER TKOF. REQUESTED PRIORITY HANDLING AND LANDED WITHOUT INCIDENT.

Narrative: I WAS PRACTICING MY PATTERN WORK AND TKOFS AND LNDG STAYING IN THE TFC PATTERN OF DXR. AT ABOUT 400' AGL, 850' MSL MY ENG STARTED TO WAKE A VERY LOUD NOISE AND RUN ROUGH. I WAS TOO HIGH TO LAND STRAIGHT AHEAD. I CONTINUED TO CLB AND CONTACTED DXR TWR TO TELL THEM THAT MY ENG IS RUNNING ROUGH AND I WOULD LIKE TO LAND AS SOON AS POSSIBLE. THEY OFFER ME RWY 35-17 BUT UPON ATTAINING PATTERN ALT I REQUESTED THE ACTIVE RWY 26-8 WHICH DID NOT HAVE A XWIND. THE TWR ASKED IF I NEEDED FIRE EQUIP WHICH I STATED, 'NOT YET.' THE TWR CLRED ME TO LAND ON RWY 26 AND HELD OTHER TFC. I MADE A SHORT APCH AND LANDED W/O INCIDENT, CLRED THE RWY AND WAS CLRED TO TAXI BACK TO MY FBO. I HAD THE ACFT REPAIRED. THE EXHAUST PIPE ON #4 CYLINDER HAD FALLEN OFF CAUSING THE NOISE AND ROUGH ENG.

Data retrieved from NASA's ASRS site as of July 2007 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.