Narrative:

I took off from arlington and climbed to 3000 ft before passing the airport sbound. My plane was to climb over the class B airspace that tops out at 10000 ft. I also called sea approach for flight following and told them my location, altitude, and direction of flight. My mistake was to take the class B description chart out to review before flight and misplaced it. I thought I was climbing to avoid the class B airspace, but after the second controller I talked to said I was in the airspace before I called, I realized that I had violated the top edge. I should have turned to avoid any possible violation of the airspace until I was sure of the boundary by finding the misplaced chart.

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Original NASA ASRS Text

Title: A LANCAIR ATP PLT FLIES INTO THE CLASS B AIRSPACE OF SEA WHEN FAILING TO REFER TO HIS CHART DURING A VFR DEP PROC FROM AWO, WA.

Narrative: I TOOK OFF FROM ARLINGTON AND CLBED TO 3000 FT BEFORE PASSING THE ARPT SBOUND. MY PLANE WAS TO CLB OVER THE CLASS B AIRSPACE THAT TOPS OUT AT 10000 FT. I ALSO CALLED SEA APCH FOR FLT FOLLOWING AND TOLD THEM MY LOCATION, ALT, AND DIRECTION OF FLT. MY MISTAKE WAS TO TAKE THE CLASS B DESCRIPTION CHART OUT TO REVIEW BEFORE FLT AND MISPLACED IT. I THOUGHT I WAS CLBING TO AVOID THE CLASS B AIRSPACE, BUT AFTER THE SECOND CTLR I TALKED TO SAID I WAS IN THE AIRSPACE BEFORE I CALLED, I REALIZED THAT I HAD VIOLATED THE TOP EDGE. I SHOULD HAVE TURNED TO AVOID ANY POSSIBLE VIOLATION OF THE AIRSPACE UNTIL I WAS SURE OF THE BOUNDARY BY FINDING THE MISPLACED CHART.

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.