Near midair collision between two small aircraft's at cma.

Attributes
ACN	152776
Time
Date	199008
Day	Thu
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : cma
State Reference	CA
Altitude	msl bound lower : 1200 msl bound upper : 1200
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : cma
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 2 Eng, Retractable Gear
Flight Phase	other
Flight Plan	VFR
Aircraft 2
Make Model Name	Small Aircraft
Flight Phase	other
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument
Experience	flight time last 90 days : 50 flight time total : 1600 flight time type : 40
ASRS Report	152776
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Events
Anomaly	conflict : nmac other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 250 vertical : 250
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

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.'

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.