Narrative:

While in a closed traffic pattern to runway 17L; with two other helicopters; aircraft X began a descending; decelerating turn for base from 600 ft. The pilot in the right seat of aircraft X saw the cessna approximately 400 ft to the right and at the same altitude making a left turn to base which put the cessna on a collision course with aircraft X. The pilot in the right seat took controls and executed a hard left turn while descending for seperation. This is the third time an incident similar to this has happened to our aircraft at this airfield.

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Original NASA ASRS Text

Title: Helicopter pilot reports NMAC with Cessna; at night during the base turn. Evasive action was taken by the reporter who also reports previous incidents have occurred at the same location.

Narrative: While in a closed traffic pattern to Runway 17L; with two other helicopters; Aircraft X began a descending; decelerating turn for base from 600 FT. The pilot in the right seat of Aircraft X saw the Cessna approximately 400 FT to the right and at the same altitude making a left turn to base which put the Cessna on a collision course with Aircraft X. The pilot in the right seat took controls and executed a hard left turn while descending for seperation. This is the third time an incident similar to this has happened to our aircraft at this airfield.

Data retrieved from NASA's ASRS site as of April 2012 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.