Narrative:

I installed a new data card in my IFR approved GPS. Upon being vectored for the approach, I put 'acy' into the GPS. I then noted the GPS was indicating this to be a fix thousands of mi away. I have used acy many times in the past without a problem. I called the GPS manufacturer, thinking there was a problem with the database. It turns out that another airport, cyt, has the same identifier (it also seems to have cyt as its identifier). I was unaware that more than 1 airport could have the same identifier. It is dangerous, in my opinion. During the high workload of an approach, this could easily be missed or overlooked, causing a serious problem, such as shooting an approach to minimums with the GPS set to the wrong airport.

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Original NASA ASRS Text

Title: A PVT PLT IS CONCERNED THAT HIS GPS DATABASE IS SHOWING 1 IDENTIFIER FOR 2 DIFFERENT ARPTS. HE CLAIMS THAT ACY AND CYT ARE ONE AND THE SAME IDENTIFIER.

Narrative: I INSTALLED A NEW DATA CARD IN MY IFR APPROVED GPS. UPON BEING VECTORED FOR THE APCH, I PUT 'ACY' INTO THE GPS. I THEN NOTED THE GPS WAS INDICATING THIS TO BE A FIX THOUSANDS OF MI AWAY. I HAVE USED ACY MANY TIMES IN THE PAST WITHOUT A PROB. I CALLED THE GPS MANUFACTURER, THINKING THERE WAS A PROB WITH THE DATABASE. IT TURNS OUT THAT ANOTHER ARPT, CYT, HAS THE SAME IDENTIFIER (IT ALSO SEEMS TO HAVE CYT AS ITS IDENTIFIER). I WAS UNAWARE THAT MORE THAN 1 ARPT COULD HAVE THE SAME IDENTIFIER. IT IS DANGEROUS, IN MY OPINION. DURING THE HIGH WORKLOAD OF AN APCH, THIS COULD EASILY BE MISSED OR OVERLOOKED, CAUSING A SERIOUS PROB, SUCH AS SHOOTING AN APCH TO MINIMUMS WITH THE GPS SET TO THE WRONG ARPT.

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.