Narrative:

Received IFR clearance informing me to expect radar vectors after takeoff. Tower cleared me for takeoff, with no heading to turn. I took off and still tower didn't give me a heading. I changed frequency to departure and before talking to them, made a left downwind departure. This is the first time at this airport for me and earlier I was with a local instructor getting an aircraft chkout. After takeoff we made a left downwind departure. That's why I made the decision to turn left. Point mugu departure implied that I didn't listen to my clearance and noted that I made a left downwind departure. I explained to them that I wasn't given a vector and earlier the left turn seemed to be authorized (runway 8 has a right traffic pattern). It was VFR conditions. The IFR departure procedure specifies to climb to 2500 ft via cma R-061 then all aircraft climbing left turn direct cma VOR DME. Callback conversation with reporter revealed the following information: reporter states first instrument flight since rating and was with very experienced pilot. Had a 'throw away' type airport diagram which did not indicate right traffic pattern. Analyst counseled reference proper charts and request frequency change versus just leaving frequency. Analyst assessment: reporter's very experienced pilot was not much help!

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Original NASA ASRS Text

Title: INST DEP, PLT CHANGES FREQ, MAKES TURN WITHOUT CLRNC TO DO SO.

Narrative: RECEIVED IFR CLRNC INFORMING ME TO EXPECT RADAR VECTORS AFTER TKOF. TWR CLRED ME FOR TKOF, WITH NO HDG TO TURN. I TOOK OFF AND STILL TWR DIDN'T GIVE ME A HDG. I CHANGED FREQ TO DEP AND BEFORE TALKING TO THEM, MADE A L DOWNWIND DEP. THIS IS THE FIRST TIME AT THIS ARPT FOR ME AND EARLIER I WAS WITH A LCL INSTRUCTOR GETTING AN ACFT CHKOUT. AFTER TKOF WE MADE A L DOWNWIND DEP. THAT'S WHY I MADE THE DECISION TO TURN L. POINT MUGU DEP IMPLIED THAT I DIDN'T LISTEN TO MY CLRNC AND NOTED THAT I MADE A L DOWNWIND DEP. I EXPLAINED TO THEM THAT I WASN'T GIVEN A VECTOR AND EARLIER THE L TURN SEEMED TO BE AUTHORIZED (RWY 8 HAS A R TFC PATTERN). IT WAS VFR CONDITIONS. THE IFR DEP PROC SPECIFIES TO CLB TO 2500 FT VIA CMA R-061 THEN ALL ACFT CLBING L TURN DIRECT CMA VOR DME. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES FIRST INST FLT SINCE RATING AND WAS WITH VERY EXPERIENCED PLT. HAD A 'THROW AWAY' TYPE ARPT DIAGRAM WHICH DID NOT INDICATE R TFC PATTERN. ANALYST COUNSELED REF PROPER CHARTS AND REQUEST FREQ CHANGE VERSUS JUST LEAVING FREQ. ANALYST ASSESSMENT: RPTR'S VERY EXPERIENCED PLT WAS NOT MUCH HELP!

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.