Narrative:

Departed ffz. I contacted sdl tower who cleared me to cross their airspace at or above 3500 ft. As I climbed, I then realized phx class B was 3000 ft (floor) around this area for a few more mi. At about 3100 ft I immediately and rapidly descended to 2700 ft. Recommend rounding out that southeast corner for transitioning aircraft.

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Original NASA ASRS Text

Title: AN SMA PLT BELIEVES THAT HE CLBED INTO THE PHX CLASS B AIRSPACE WITHOUT TRACON CLRNC.

Narrative: DEPARTED FFZ. I CONTACTED SDL TWR WHO CLRED ME TO CROSS THEIR AIRSPACE AT OR ABOVE 3500 FT. AS I CLBED, I THEN REALIZED PHX CLASS B WAS 3000 FT (FLOOR) AROUND THIS AREA FOR A FEW MORE MI. AT ABOUT 3100 FT I IMMEDIATELY AND RAPIDLY DSNDED TO 2700 FT. RECOMMEND ROUNDING OUT THAT SE CORNER FOR TRANSITIONING ACFT.

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.