Narrative:

I had taken off from sgs to the north and immediately made a left turn to head south to stay out of st. Paul downtown airport's airspace. I knew I had to stay below 2;300 ft on my initial climb then; once outside the initial ring (actually the second ring of the msp class B airspace) I could climb; but had to stay below 3;000 ft. I was using an ipad as a sectional with GPS. [The flight application I use] gives me a visual of my airplane against the VFR sectional background. My passenger was holding the ipad on her lap as there was a great deal of turbulence and I felt it easier for her to hold and angle the ipad so I could use it as a reference in transitioning various airspace. I climbed to 2;500 ft within the secondary ring outside sgs (third ring from msp) to stay below the 3;000 ft ceiling of the class B airspace. After what seemed several minutes; I glanced down to the sectional and saw that I had exited the second ring from sgs and continued my climb. For some reason; in my observation of holding the aircraft in the turbulence and taking short views at the sectional; I thought I was already clear of the next ring of airspace 100/40; and began my climb to my cruise altitude of 5;500 ft. With a tailwind; the climb was slow. As I was climbing; and I believe I was above 5;000 ft already; I took another glance down at the sectional and then noticed that I had not yet left the 100/40 airspace. I immediately reduced power and quickly descended to below the 4;000 ft level; leveling off near 3;500 ft MSL. I realized that I was in violation of the airspace and held 3;500 ft well beyond the outer portion of the ring until turbulence forced me to regain altitude to 5;500 ft; outside the controlled airspace.

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Original NASA ASRS Text

Title: C172 pilot reports inadvertently entering MSP class B airspace during a southbound departure from SGS using an iPad with GPS to determine position relative to the class B. An error is made interpreting the display and the reporter climbs early into the 4;000 FT ring. When the error is detected a descent is initiated to 3;500 FT.

Narrative: I had taken off from SGS to the north and immediately made a left turn to head south to stay out of St. Paul Downtown Airport's airspace. I knew I had to stay below 2;300 FT on my initial climb then; once outside the initial ring (actually the second ring of the MSP class B airspace) I could climb; but had to stay below 3;000 FT. I was using an iPad as a sectional with GPS. [The flight application I use] gives me a visual of my airplane against the VFR sectional background. My passenger was holding the iPad on her lap as there was a great deal of turbulence and I felt it easier for her to hold and angle the iPad so I could use it as a reference in transitioning various airspace. I climbed to 2;500 FT within the secondary ring outside SGS (third ring from MSP) to stay below the 3;000 FT ceiling of the class B airspace. After what seemed several minutes; I glanced down to the sectional and saw that I had exited the second ring from SGS and continued my climb. For some reason; in my observation of holding the aircraft in the turbulence and taking short views at the sectional; I thought I was already clear of the next ring of airspace 100/40; and began my climb to my cruise altitude of 5;500 FT. With a tailwind; the climb was slow. As I was climbing; and I believe I was above 5;000 FT already; I took another glance down at the sectional and then noticed that I had not yet left the 100/40 airspace. I immediately reduced power and quickly descended to below the 4;000 FT level; leveling off near 3;500 FT MSL. I realized that I was in violation of the airspace and held 3;500 FT well beyond the outer portion of the ring until turbulence forced me to regain altitude to 5;500 FT; outside the controlled airspace.

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.