Narrative:

This report identifies my first experience using an ipad and recently purchased navigation software that generates a moving map presentation on geo-referenced sectional charts. During the flight described below; I relied primarily on the ipad 3G (the model containing the GPS chip) to assist me in remaining clear of class C and class D airspace. Upon returning home and after thinking about it for a few hours; I'm not sure that this moving map ipad software was accurate enough to assist me in remaining clear of that airspace. I departed enroute to sbd. My route took me east and north of the first class C airspace at 2;400 ft; allowing me to avoid the class C shelf to the west. From there I navigated to ajo; then direct to sbd at 2;400 ft MSL. During the trip I primarily referenced my ipad's moving map software to provide sufficient clearance from the boundaries of a nearby class C airspace and cno's class D airspace. When passing just a bit north of ajo airport; I decided to change the map's scale for a closer look at cno's class D boundary. On the slightly larger map scale that I had been using; the moving 's airplane icon was positioned outside the boundary of cno's class D airspace and the ipad's GPS accuracy meter showed five meters. This seemed to comport with the horizontal displacement from ajo airport that I viewed outside the cockpit window. The moment I reduced the map's scale; however; the airplane icon was displaced slightly inside the boundary of cno's class D airspace. Since cno's class D airspace extends to 2;700 ft MSL; this put me 300 ft below the top of this airspace. When I further reduced the moving map's scale; the airplane icon was further displaced inside class D airspace. It was clear that the position of the moving map's airplane icon shifted noticeably (perhaps by two miles) with variable scale settings. At that point I reverted solely to using the terminal and sectional charts for navigation. The rest of the flight to and from sbd was conducted without use of the ipad's moving map software. Upon returning home later that evening; I examined my route east and north on the ipad's moving map software. On the medium range scale; my route appears to have taken me clear of class C airspace and cno's class D airspace. Upon reducing the scale; it shows that I might have clipped corners on both of these airspace structures. I have a lot of experience with different types of moving map displays using geo-referenced sectional charts and most have been reasonably accurate. I didn't suspect that the ipad's moving map display would be any different; especially since its positional accuracy showed +/- five meters. It's my standard practice to use pilotage to verify any moving map information. On this flight; however; I might have relied on the ipad a little too much; thus possibly causing me to clip class C and class D airspace without establishing the appropriate communications. Why did I allow this to happen? I simply placed too much trust in the ipad's moving map information and didn't use pilotage often enough to verify its accuracy. While it appeared that I had a reasonable displacement from class C and D airspace boundaries using the map's medium range scale; this might not have been the case. While this may be a serious issue with this particular moving map display; it's ultimately more an issue with me; the pilot. Normally I don't rely 'solely' on moving map information for avoiding some types of airspace. Clearly this was an amateur's mistake on my part. At this point I'm not sure why the ipad's software is having difficulty with accurate placement of the moving map airplane icon. This is something I'll have to research. Nevertheless; it's clear that scaling the moving map changes the geographical position of the airplane displayed on the moving map; despite the GPS engine providing accuracy within +/- five meters.

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Original NASA ASRS Text

Title: A VFR pilot reported using an iPad to navigate in the LAX area's complex airspace and possibly entered Class C and Class D airspace.

Narrative: This report identifies my first experience using an iPad and recently purchased navigation software that generates a moving map presentation on geo-referenced sectional charts. During the flight described below; I relied primarily on the iPad 3G (the model containing the GPS chip) to assist me in remaining clear of Class C and Class D airspace. Upon returning home and after thinking about it for a few hours; I'm not sure that this moving map iPad software was accurate enough to assist me in remaining clear of that airspace. I departed enroute to SBD. My route took me east and north of the first Class C airspace at 2;400 FT; allowing me to avoid the Class C shelf to the west. From there I navigated to AJO; then direct to SBD at 2;400 FT MSL. During the trip I primarily referenced my iPad's moving map software to provide sufficient clearance from the boundaries of a nearby Class C airspace and CNO's Class D airspace. When passing just a bit north of AJO airport; I decided to change the map's scale for a closer look at CNO's Class D boundary. On the slightly larger map scale that I had been using; the moving 's airplane icon was positioned outside the boundary of CNO's Class D airspace and the iPad's GPS accuracy meter showed five meters. This seemed to comport with the horizontal displacement from AJO airport that I viewed outside the cockpit window. The moment I reduced the map's scale; however; the airplane icon was displaced slightly inside the boundary of CNO's Class D airspace. Since CNO's Class D airspace extends to 2;700 FT MSL; this put me 300 FT below the top of this airspace. When I further reduced the moving map's scale; the airplane icon was further displaced inside Class D airspace. It was clear that the position of the moving map's airplane icon shifted noticeably (perhaps by two miles) with variable scale settings. At that point I reverted solely to using the terminal and sectional charts for navigation. The rest of the flight to and from SBD was conducted without use of the iPad's moving map software. Upon returning home later that evening; I examined my route east and north on the iPad's moving map software. On the medium range scale; my route appears to have taken me clear of Class C airspace and CNO's Class D airspace. Upon reducing the scale; it shows that I might have clipped corners on both of these airspace structures. I have a lot of experience with different types of moving map displays using geo-referenced sectional charts and most have been reasonably accurate. I didn't suspect that the iPad's moving map display would be any different; especially since its positional accuracy showed +/- five meters. It's my standard practice to use pilotage to verify any moving map information. On this flight; however; I might have relied on the iPad a little too much; thus possibly causing me to clip Class C and Class D airspace without establishing the appropriate communications. Why did I allow this to happen? I simply placed too much trust in the iPad's moving map information and didn't use pilotage often enough to verify its accuracy. While it appeared that I had a reasonable displacement from Class C and D airspace boundaries using the map's medium range scale; this might not have been the case. While this may be a serious issue with this particular moving map display; it's ultimately more an issue with me; the pilot. Normally I don't rely 'solely' on moving map information for avoiding some types of airspace. Clearly this was an amateur's mistake on my part. At this point I'm not sure why the iPad's software is having difficulty with accurate placement of the moving map airplane icon. This is something I'll have to research. Nevertheless; it's clear that scaling the moving map changes the geographical position of the airplane displayed on the moving map; despite the GPS engine providing accuracy within +/- five meters.

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.