Narrative:

I took off from a nearby airport about ten minutes prior to the incident. I was taking my friend on the left seat; and giving him a recreational flight vicinity of the town. About six miles out; I made an initial radio contact to our destination tower; and requested touch-and-go at the field. Tower goes 'touch-and-go approved; report left base for runway 30. You are following C-150 ahead.'I immediately found the aircraft about two to three miles ahead of us; and told tower; 'I have traffic in sight.' when I flew into the airspace; about three to four miles out; I saw the aircraft was making a left base entry. After a minute or so; I started to turn for base entry at where I believed the traffic ahead made the left base entry; and then I made a radio call. 'Report left base established'. I tried to make the same space traffic pattern. Shortly after I made the left base entry; I lost sight of the aircraft. However I continued to descend at approximately 80 KTS with descent rate of 400-500 FPM. Then just prior to make a turn to final; I saw an airplane flying towards us at normal approaching speed. I knew they were below us; thus I immediately added full-power and executed steep climb. At the same time; I heard a radio call from tower; 'maintain north heading.' then; I complied with it. When I saw the traffic; it was about two O'clock and 100-200 ft below us. It was right before I was making a turn to final; I took a quick glance at the right side for extended final. A probable cause of the incident could be my scanning after establishing base entry; I was spending too much time orienting myself by keeping an eye on the runway. Also; my division of attention between looking at the airport and traffic was getting poor. I wondered why the traffic suddenly disappeared from my sight after I established left base; and it took so long for them to establish final approach. Only I can think of is they are doing 360 turn or something for spacing. Although this incident could be an FAA-defined near midair collision; due to the uncertain distance between the two airplanes; I hesitated to complete near midair collision report to FAA.

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Original NASA ASRS Text

Title: A C-172 and a C-150 experienced an NMAC while entering the traffic pattern at a controlled airport.

Narrative: I took off from a nearby airport about ten minutes prior to the incident. I was taking my friend on the left seat; and giving him a recreational flight vicinity of the town. About six miles out; I made an initial radio contact to our destination Tower; and requested touch-and-go at the field. Tower goes 'Touch-and-go approved; report left base for Runway 30. You are following C-150 ahead.'I immediately found the aircraft about two to three miles ahead of us; and told Tower; 'I have traffic in sight.' When I flew into the airspace; about three to four miles out; I saw the aircraft was making a left base entry. After a minute or so; I started to turn for base entry at where I believed the traffic ahead made the left base entry; and then I made a radio call. 'Report left base established'. I tried to make the same space traffic pattern. Shortly after I made the left base entry; I lost sight of the aircraft. However I continued to descend at approximately 80 KTS with descent rate of 400-500 FPM. Then just prior to make a turn to final; I saw an airplane flying towards us at normal approaching speed. I knew they were below us; thus I immediately added full-power and executed steep climb. At the same time; I heard a radio call from Tower; 'Maintain North Heading.' Then; I complied with it. When I saw the traffic; it was about two O'clock and 100-200 FT below us. It was right before I was making a turn to final; I took a quick glance at the right side for extended final. A probable cause of the incident could be my scanning after establishing base entry; I was spending too much time orienting myself by keeping an eye on the runway. Also; my division of attention between looking at the airport and traffic was getting poor. I wondered why the traffic suddenly disappeared from my sight after I established left base; and it took so long for them to establish final approach. Only I can think of is they are doing 360 turn or something for spacing. Although this incident could be an FAA-defined NMAC; due to the uncertain distance between the two airplanes; I hesitated to complete NMAC report to FAA.

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.