Narrative:

Aircraft #1 entered the pattern of runway 1R on the right 45 degree. I didn't see aircraft #2 on downwind until 500 ft distance. I made a course change to the right as aircraft #2 continued downwind. I extended downwind and landed after aircraft #2. Cause: my failure to make visual contact and ATC's failure to warn of traffic. Prevention: better heads-up from myself when I am approaching to land.

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Original NASA ASRS Text

Title: A C172 PLT HAD AN NMAC WITH A C150 WHILE ON THE ENTRY LEG INTO THE TFC PATTERN AT CCR. THE C150 WAS A TRAINING FLT.

Narrative: ACFT #1 ENTERED THE PATTERN OF RWY 1R ON THE R 45 DEG. I DIDN'T SEE ACFT #2 ON DOWNWIND UNTIL 500 FT DISTANCE. I MADE A COURSE CHANGE TO THE R AS ACFT #2 CONTINUED DOWNWIND. I EXTENDED DOWNWIND AND LANDED AFTER ACFT #2. CAUSE: MY FAILURE TO MAKE VISUAL CONTACT AND ATC'S FAILURE TO WARN OF TFC. PREVENTION: BETTER HEADS-UP FROM MYSELF WHEN I AM APCHING TO LAND.

Data retrieved from NASA's ASRS site as of July 2007 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.