Narrative:

While on a VFR flight to morristown municipal (mmu); my GPS showed I was 8 miles out at 1500 feet from morristown municipal airport when I radio the tower control to announce my intentions to land full stop; ATC cleared me for left downwind runway 31 and report mid field downwind then asked me to ident. After I idented ATC indicated I was 5 miles south; which still puts me outside of the class D airspace at the time I checked in with ATC since the class D airspace at morristown municipal is within 4.1 NM radius of the airport according to FAA order jo 7400.9Y date august 06; 2014 page 223.I feel the GPS was misleading me and want to make sure this information is documented in case there is a bad GPS signal in the area and other pilots report the same situation in the area in the future.

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Original NASA ASRS Text

Title: PA28 pilot reports checking in with MMU Tower 8 NM out; according to his GPS; then told to ident. The Tower indicates that he is 5 NM south and the reporter believes that there may be a bad GPS signal in this area.

Narrative: While on a VFR flight to Morristown Municipal (MMU); my GPS showed I was 8 miles out at 1500 feet from Morristown Municipal Airport when I radio the Tower Control to announce my intentions to land full stop; ATC cleared me for left downwind Runway 31 and report mid field downwind then asked me to ident. After I idented ATC indicated I was 5 miles south; which still puts me outside of the Class D airspace at the time I checked in with ATC since the Class D airspace at Morristown Municipal is within 4.1 NM radius of the airport according to FAA Order JO 7400.9Y date August 06; 2014 page 223.I feel the GPS was misleading me and want to make sure this information is documented in case there is a bad GPS signal in the area and other pilots report the same situation in the area in the future.

Data retrieved from NASA's ASRS site 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.