Narrative:

I contacted ZZZ approach with information of my intention to land at my destination. Close to entering the pattern I requested a change to CTAF that was approved and I was instructed to squawk VFR. While in the right downwind for runway xx and close to turning right base I suddenly saw [another aircraft] at my 11:00 o'clock. The sighting lasted 10 seconds; including a full view of the aircraft about 250' away on my left and at same flight level. I turned to base afterward. I did transmit that a plane had come very close to me while in the pattern. Nobody responded. After landing and while on the runway I communicated with an airplane approaching to land that I was about to clear the runway. I did not check to see if it was the plane I had seen before in the pattern. What I learned: always make sure to have the landing light on prior to entering a landing patter; or when taking-off from an airport. I normally do this but I forgot since the last time I flew my plane was over 2 months ago. Flying more frequently is another lesson for me. I suggest that ATC directs a departing aircraft in the direction of a secondary airport to provide a heading directly above the runway to avoid that aircraft from entering the landing pattern. Also; ATC should ensure that aircraft heading in the direction of class D secondary airport have their landing light on. Same suggestion for aircraft landing at secondary airport. Other lesson I learned is the importance of landing by entering the active runway downwind leg. Had I entered the pattern via the right base; as I used to do and other pilots I observed doing; I would not have seen the interfering aircraft although I would have made a larger picture for him to see.

Related reports:

Google
 

Original NASA ASRS Text

Title: The pilot of a C140 experienced a NMAC with a low wing aircraft while entering the pattern at a non-towered airport.

Narrative: I contacted ZZZ Approach with information of my intention to land at my destination. Close to entering the pattern I requested a change to CTAF that was approved and I was instructed to squawk VFR. While in the right downwind for Runway XX and close to turning right base I suddenly saw [another aircraft] at my 11:00 o'clock. The sighting lasted 10 seconds; including a full view of the aircraft about 250' away on my left and at same flight level. I turned to base afterward. I did transmit that a plane had come very close to me while in the pattern. Nobody responded. After landing and while on the runway I communicated with an airplane approaching to land that I was about to clear the runway. I did not check to see if it was the plane I had seen before in the pattern. What I learned: Always make sure to have the landing light on prior to entering a landing patter; or when taking-off from an airport. I normally do this but I forgot since the last time I flew my plane was over 2 months ago. Flying more frequently is another lesson for me. I suggest that ATC directs a departing aircraft in the direction of a secondary airport to provide a heading directly above the runway to avoid that aircraft from entering the landing pattern. Also; ATC should ensure that aircraft heading in the direction of Class D secondary airport have their landing light on. Same suggestion for aircraft landing at secondary airport. Other lesson I learned is the importance of landing by entering the active runway downwind leg. Had I entered the pattern via the right base; as I used to do and other pilots I observed doing; I would not have seen the interfering aircraft although I would have made a larger picture for him to see.

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.