Narrative:

On IFR flight plan under ATC control. Completing climb to 3000 ft MSL reported cloud layer canceled IFR for VFR on top. Told to turn right to 240 degrees and track dumbarton bridge on left. Plan was to fly to ccr and vector did not seem correct; but I repeated the instruction and was not told anything was wrong in read back. Vector took aircraft near sfo airport. Then told to turn left to pao; fly toward pao then turn left keeping dumbarton bridge on left. Over clouds at this point; turned left and hear aircraft on final to sfo directed for aircraft (my aircraft). Approaching captain on sfo flight questioned why a cessna was in his way. ATC responded 'cessna made a wrong turn.' I was never told by ATC that I made a wrong turn at anytime. I believe this could have been avoided if I had asked for clarification on the turn: right to 240. A more correct heading should have been left to 040.

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Original NASA ASRS Text

Title: SQL departure that IFR cancelled and was receiving flight following with NCT; described confused turn instruction that resulted in a conflict with an SFO arrival; reporter claiming NCT never made mention of the wrong turn.

Narrative: On IFR flight plan under ATC control. Completing climb to 3000 FT MSL reported cloud layer canceled IFR for VFR on top. Told to turn R to 240 degrees and track Dumbarton Bridge on left. Plan was to fly to CCR and vector did not seem correct; but I repeated the instruction and was not told anything was wrong in read back. Vector took aircraft near SFO airport. Then told to turn left to PAO; fly toward PAO then turn L keeping Dumbarton Bridge on left. Over clouds at this point; turned L and hear aircraft on final to SFO directed for aircraft (my aircraft). Approaching Captain on SFO flight questioned why a Cessna was in his way. ATC responded 'Cessna made a wrong turn.' I was never told by ATC that I made a wrong turn at anytime. I believe this could have been avoided if I had asked for clarification on the turn: right to 240. A more correct heading should have been left to 040.

Data retrieved from NASA's ASRS site as of April 2012 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.