Narrative:

Prior to takeoff, fxe tower clearance was 'cleared for takeoff, runway 26, stay clear of class C airspace.' at the time I believed class C went to the surface so the clearance did not make sense. The tower was too busy to question. I assumed he meant to exit class C as soon as practical. After leveling off at about 2500 ft and checking the chart, I realized that class C at that location began at 1200 ft. The initial clearance was now clear. I immediately descended to 1100 ft. This was simply a mistake. The chart was clear. I should have known better. I do not use fxe often so my familiarity with the area is marginal if fxe tower had cleared 'stay below 1200 ft until clear of class C airspace' would have prevented the incident, but the responsibility was mine. I am not trying to shift blame.

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Original NASA ASRS Text

Title: A COMMERCIAL INST RATED PLT FLYING A C172 FROM FXE ALLOWED HIS ACFT TO CLB INTO CLASS C AIRSPACE WITHOUT PROPER CLRNC.

Narrative: PRIOR TO TKOF, FXE TWR CLRNC WAS 'CLRED FOR TKOF, RWY 26, STAY CLR OF CLASS C AIRSPACE.' AT THE TIME I BELIEVED CLASS C WENT TO THE SURFACE SO THE CLRNC DID NOT MAKE SENSE. THE TWR WAS TOO BUSY TO QUESTION. I ASSUMED HE MEANT TO EXIT CLASS C AS SOON AS PRACTICAL. AFTER LEVELING OFF AT ABOUT 2500 FT AND CHKING THE CHART, I REALIZED THAT CLASS C AT THAT LOCATION BEGAN AT 1200 FT. THE INITIAL CLRNC WAS NOW CLR. I IMMEDIATELY DSNDED TO 1100 FT. THIS WAS SIMPLY A MISTAKE. THE CHART WAS CLR. I SHOULD HAVE KNOWN BETTER. I DO NOT USE FXE OFTEN SO MY FAMILIARITY WITH THE AREA IS MARGINAL IF FXE TWR HAD CLRED 'STAY BELOW 1200 FT UNTIL CLR OF CLASS C AIRSPACE' WOULD HAVE PREVENTED THE INCIDENT, BUT THE RESPONSIBILITY WAS MINE. I AM NOT TRYING TO SHIFT BLAME.

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.