Narrative:

The emergency occurred after doing several takeoffs and landings. At approximately 100 ft AGL on takeoff; I experienced a partial loss of power. I quickly lowered the nose; reduced the power; and put on the carb heat. I determined I could not land on the remaining runway and it was doubtful if I could land straight ahead without hitting the airport perimeter fence. I elected to make a 40 degree turn to the right to land in a plowed field. At this point I keyed the mike and said; 'mayday.' after making the turn; the engine was still producing power; so I made another 40 degree turn to land across the airport property. After that turn; I then had the option to land on the grass runway. At this time; I did a second call to the tower and repeated 'mayday' three times. It is possible I stepped on a tower transmission to clear a mooney for takeoff. On short final to the grass crosswind runway; I heard the tower hold the mooney in position for me. I landed uneventfully on the sod runway and requested to taxi to the hangers which was given. After taxiing to my hangar; I called the tower on my cell phone and thanked them for their help and verified they heard my 'mayday' call. They said they did hear it once and they were happy that I was able to land safely. The only regulations that I may have broken are that I didn't follow ATC instructions for left traffic and I landed on the sod runway without a clearance. Declaring an emergency lifted both of these responsibilities plus any others I didn't think of. I only did what I had to do to make a successful outcome of a partial-power loss.

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Original NASA ASRS Text

Title: C120 pilot experiences a partial power loss on takeoff after completing several touch and go landings and announces 'Mayday' on Tower frequency. While turning toward a plowed field it is determined that sufficient power is available to continue the turn and land on an intersecting runway after announcing 'Mayday' several more times.

Narrative: The emergency occurred after doing several takeoffs and landings. At approximately 100 FT AGL on takeoff; I experienced a partial loss of power. I quickly lowered the nose; reduced the power; and put on the carb heat. I determined I could not land on the remaining runway and it was doubtful if I could land straight ahead without hitting the airport perimeter fence. I elected to make a 40 degree turn to the right to land in a plowed field. At this point I keyed the mike and said; 'Mayday.' After making the turn; the engine was still producing power; so I made another 40 degree turn to land across the airport property. After that turn; I then had the option to land on the grass runway. At this time; I did a second call to the tower and repeated 'Mayday' three times. It is possible I stepped on a tower transmission to clear a Mooney for takeoff. On short final to the grass crosswind runway; I heard the tower hold the Mooney in position for me. I landed uneventfully on the sod runway and requested to taxi to the hangers which was given. After taxiing to my hangar; I called the Tower on my cell phone and thanked them for their help and verified they heard my 'Mayday' call. They said they did hear it once and they were happy that I was able to land safely. The only regulations that I may have broken are that I didn't follow ATC instructions for left traffic and I landed on the sod runway without a clearance. Declaring an emergency lifted both of these responsibilities plus any others I didn't think of. I only did what I had to do to make a successful outcome of a partial-power loss.

Data retrieved from NASA's ASRS site as of July 2013 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.