Narrative:

Flying into a non towered airport; I reported fifteen east; then ten east and then six miles east to advise that I was planning a left downwind entry to runway 16. A cherokee advised that he was five west of the airport and was planning on crossing mid field for a left downwind to runway 16. Upon entering left downwind at pattern altitude I advised that I did not have the cherokee in sight and requested his position. He reported that he was off my left wing on a right downwind; had me in sight and would follow me.I asked the cherokee why he didn't enter left downwind like he said. He stated that he was planning on it until I was going to be there. He stated that he had me in sight and would follow me. I acknowledged and said that I would make a short approach. I dropped my gear; applied twenty degrees of flaps; cut the power in order to make a short approach given my downwind airspeed. After I turned on base I observed the cherokee at my 11:00 position on a short right hand base at my altitude and no more than 150 ft away. I added power; pulled up ten degrees of flaps and banked to the right for a right 360 to follow him in. I was less than 300 ft above the ground with my gear down and power to idle when I had to make the maneuver to avoid the cherokee.being an FAA controller for ten years and flying for nearly forty this was the worst situation I've been in. The pilot in the cherokee should not be flying or at least not without some serious retraining. The pilot; who I approached after the incident; said that he was based at the airport. I advised him that I was filing a report.

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Original NASA ASRS Text

Title: A C-177RG turning onto short final approach suffered an NMAC with a PA28 whose pilot failed to comply with the standard traffic pattern at a non towered airport.

Narrative: Flying into a non towered airport; I reported fifteen east; then ten east and then six miles east to advise that I was planning a left downwind entry to Runway 16. A Cherokee advised that he was five west of the airport and was planning on crossing mid field for a left downwind to Runway 16. Upon entering left downwind at pattern altitude I advised that I did not have the Cherokee in sight and requested his position. He reported that he was off my left wing on a right downwind; had me in sight and would follow me.I asked the Cherokee why he didn't enter left downwind like he said. He stated that he was planning on it until I was going to be there. He stated that he had me in sight and would follow me. I acknowledged and said that I would make a short approach. I dropped my gear; applied twenty degrees of flaps; cut the power in order to make a short approach given my downwind airspeed. After I turned on base I observed the Cherokee at my 11:00 position on a short right hand base at my altitude and no more than 150 FT away. I added power; pulled up ten degrees of flaps and banked to the right for a right 360 to follow him in. I was less than 300 FT above the ground with my gear down and power to idle when I had to make the maneuver to avoid the Cherokee.Being an FAA controller for ten years and flying for nearly forty this was the worst situation I've been in. The pilot in the Cherokee should not be flying or at least not without some serious retraining. The pilot; who I approached after the incident; said that he was based at the airport. I advised him that I was filing a report.

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.