Narrative:

[We were] cleared visual approach into fty. First officer said fty airport straight ahead 2 miles away. I looked at the airport and then started to enter a left downwind heading west for landing runway east. I then realized that I was entering left down wind to dobbins AFB. I then proceeded to turn south to fty. Altitude was 3;000 MSL; atl control contacted us and said don't go below 3;000 MSL. Our GPWS activated saying terrain; pull up; pull up? We were in visual conditions and had no terrain or obstacles in our flight path? The highest obstacle in the area was 1;800 ft MSL. Not sure why GPWS activated; but I should've confirmed with atl ATC of correct airport and scaled down inav mile view to confirm.

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Original NASA ASRS Text

Title: A Falcon 2000 Captain; cleared for a visual approach; initially mistook Dobbins AFB for his destination airport and set up for a downwind. When he later altered course to correct the GPWS issued an unexplained Terrain GPWS warning.

Narrative: [We were] cleared visual approach into FTY. First Officer said FTY airport straight ahead 2 miles away. I looked at the airport and then started to enter a left downwind heading west for landing runway east. I then realized that I was entering left down wind to Dobbins AFB. I then proceeded to turn south to FTY. Altitude was 3;000 MSL; ATL Control contacted us and said don't go below 3;000 MSL. Our GPWS activated saying terrain; pull up; pull up? We were in visual conditions and had no terrain or obstacles in our flight path? The highest obstacle in the area was 1;800 FT MSL. Not sure why GPWS activated; but I should've confirmed with ATL ATC of correct airport and scaled down INAV mile view to confirm.

Data retrieved from NASA's ASRS site as of July 2013 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.