Narrative:

I was en route from french valley, ca, airport (F70) to laverne, ca, airport (poc) cruising at 3000 ft MSL. As I approached corona airport (L66), I contacted chino tower rather than socal approach, which would have been appropriate for the altitude I was at. Chino airspace extends upward to 2699 ft MSL and ontario class B begins at 2700 ft MSL. This should have been obvious to me as I had the terminal area chart (lax) open on my lap. It was an exceptionally clear day with 30+ mi visibility throughout the los angeles basin and considerable VFR traffic compared to a more normal, hazy sunday, and I was preoccupied with the potential for midair conflicts, especially in the vicinity of corona airport which is uncontrolled. It was for this reason I was at 3000 ft rather than 2000 ft or 2500 ft. However, this does not completely explain why I did not notice something so plainly marked on the chart. I contacted laverne/brackett tower 10-12 mi out. At that time the controller asked me if I had been talking to socal approach. I told him I had been talking to chino tower. It was then that I realized my mistake. The chino controller was very busy and did not notice that I was above his airspace either.

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Original NASA ASRS Text

Title: PLT OF AN SMA SEL ENTERED CLASS C AIRSPACE WITHOUT FIRST CONTACTING THE CTLING TRACON ATC FACILITY.

Narrative: I WAS ENRTE FROM FRENCH VALLEY, CA, ARPT (F70) TO LAVERNE, CA, ARPT (POC) CRUISING AT 3000 FT MSL. AS I APCHED CORONA ARPT (L66), I CONTACTED CHINO TWR RATHER THAN SOCAL APCH, WHICH WOULD HAVE BEEN APPROPRIATE FOR THE ALT I WAS AT. CHINO AIRSPACE EXTENDS UPWARD TO 2699 FT MSL AND ONTARIO CLASS B BEGINS AT 2700 FT MSL. THIS SHOULD HAVE BEEN OBVIOUS TO ME AS I HAD THE TERMINAL AREA CHART (LAX) OPEN ON MY LAP. IT WAS AN EXCEPTIONALLY CLR DAY WITH 30+ MI VISIBILITY THROUGHOUT THE LOS ANGELES BASIN AND CONSIDERABLE VFR TFC COMPARED TO A MORE NORMAL, HAZY SUNDAY, AND I WAS PREOCCUPIED WITH THE POTENTIAL FOR MIDAIR CONFLICTS, ESPECIALLY IN THE VICINITY OF CORONA ARPT WHICH IS UNCTLED. IT WAS FOR THIS REASON I WAS AT 3000 FT RATHER THAN 2000 FT OR 2500 FT. HOWEVER, THIS DOES NOT COMPLETELY EXPLAIN WHY I DID NOT NOTICE SOMETHING SO PLAINLY MARKED ON THE CHART. I CONTACTED LAVERNE/BRACKETT TWR 10-12 MI OUT. AT THAT TIME THE CTLR ASKED ME IF I HAD BEEN TALKING TO SOCAL APCH. I TOLD HIM I HAD BEEN TALKING TO CHINO TWR. IT WAS THEN THAT I REALIZED MY MISTAKE. THE CHINO CTLR WAS VERY BUSY AND DID NOT NOTICE THAT I WAS ABOVE HIS AIRSPACE EITHER.

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.