Narrative:

Entering cma traffic pattern at approximately 1200' MSL from southwest, 45 degree entry (sun was 20 degrees or more above horizontal from west). Tower instructed me to enter 45 degree, southwest report 2 mi out. Also advised small aircraft Y in pattern (I was approximately 5 NM when so instructed). Called tower at 2 mi on 45 when within 1/2 mi of normal downwind leg. Small aircraft Y entered my field of vision (to left of my aircraft) from rear quarter position, other aircraft wider and higher than usual. I turned right, he dove down. 'In my opinion unnecessarily.'

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Original NASA ASRS Text

Title: NMAC BETWEEN TWO SMA'S AT CMA.

Narrative: ENTERING CMA TFC PATTERN AT APPROX 1200' MSL FROM SW, 45 DEG ENTRY (SUN WAS 20 DEGS OR MORE ABOVE HORIZ FROM W). TWR INSTRUCTED ME TO ENTER 45 DEG, SW RPT 2 MI OUT. ALSO ADVISED SMA Y IN PATTERN (I WAS APPROX 5 NM WHEN SO INSTRUCTED). CALLED TWR AT 2 MI ON 45 WHEN WITHIN 1/2 MI OF NORMAL DOWNWIND LEG. SMA Y ENTERED MY FIELD OF VISION (TO L OF MY ACFT) FROM REAR QUARTER POS, OTHER ACFT WIDER AND HIGHER THAN USUAL. I TURNED R, HE DOVE DOWN. 'IN MY OPINION UNNECESSARILY.'

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.