Narrative:

Pleasure trip originating from shannon/fredericksburg (ezf) to easton (esn), and return to shannon on VFR. Incident occurred on return flight. GPS was in use. Was informed upon landing that I had violated washington dc ADIZ by ATC potomac approach. Flew arc around ADIZ airspace to avoid transgression, but evidently inadvertently cut through a portion of the airspace. GPS does not exhibit ADIZ airspace though it does show dca airspace. To prevent recurrence in the future, file an IFR flight plan or give area a wider berth.

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Original NASA ASRS Text

Title: PA23 ENTERS SOUTHERN EXTENSION OF DC ADIZ WITHOUT AUTH WHILE ON VFR FLT FROM ESN TO EZF.

Narrative: PLEASURE TRIP ORIGINATING FROM SHANNON/FREDERICKSBURG (EZF) TO EASTON (ESN), AND RETURN TO SHANNON ON VFR. INCIDENT OCCURRED ON RETURN FLT. GPS WAS IN USE. WAS INFORMED UPON LNDG THAT I HAD VIOLATED WASHINGTON DC ADIZ BY ATC POTOMAC APCH. FLEW ARC AROUND ADIZ AIRSPACE TO AVOID TRANSGRESSION, BUT EVIDENTLY INADVERTENTLY CUT THROUGH A PORTION OF THE AIRSPACE. GPS DOES NOT EXHIBIT ADIZ AIRSPACE THOUGH IT DOES SHOW DCA AIRSPACE. TO PREVENT RECURRENCE IN THE FUTURE, FILE AN IFR FLT PLAN OR GIVE AREA A WIDER BERTH.

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.