ENRTE C182 PLT; 6B6 TO DAN; INCURS NY ADIZ AT 12500 FT. ACFT INTERCEPT AND INTERVIEW CONDUCTED BY US CUSTOMS.

Narrative

I WAS FLYING VFR FROM 6B6 TO DAN AND I UNINTENTIONALLY VIOLATED THE NY ADIZ. I WAS FLYING AT 12500 FEET; HAD NOT FILED A FLT PLAN; WAS NOT USING FLT FOLLOWING; AND WAS SQUAWKING VFR (1200). I CAME WITHIN APPROX 23 NM OF EWR. I THOUGHT THE ADIZ CONSISTED OF THE AIRSPACE FROM THE SURFACE; UP TO; BUT NOT INCLUDING 18000 FT; WITHIN A 30 NM RADIUS OF JFK ONLY; NOT THE OTHER 2 ARPTS. I BELIEVE THERE WAS A PREVIOUS NOTAM DEFINING A NY AREA ADIZ THAT ONLY INCLUDED A 30 NM RADIUS AROUND JFK. I WAS FAMILIAR WITH THAT NOTAM; THEN IT WAS CANCELED AND LATER; THE NEWER; MORE RESTRICTIVE NOTAM WAS ISSUED. I MADE THE MISTAKE OF ASSUMING THAT THE NEW NOTAM INCLUDED THE SAME AREA AS THE OLD ONE. WHEN I CALLED THE FSS BEFORE MY FLT; I ASKED FOR A STANDARD BRIEFING; BUT I ALSO TOLD THE BRIEFER THAT I WAS FAMILIAR WITH THE NY AND WASHINGTON AREA ADIZ'S. I WAS TRACKED BY THE NY TRACON AND WAS INTERCEPTED BY A US CUSTOMS JET. AT FIRST I DID NOT BELIEVE I HAD VIOLATED THE ADIZ. I DREW MY FLT PATH ON THE NY SECTIONAL AND REVIEWED FDC NOTAM REALIZING THAT I HAD VIOLATED THE ADIZ. I SHOULD HAVE REVIEWED THE NOTAM IN DETAIL BEFORE THE FLT AND NOT MADE ANY ASSUMPTIONS BASED ON PRIOR KNOWLEDGE. ALSO; IF I HAD USED FLT FOLLOWING; ATC WOULD HAVE WARNED ME BEFORE I ENTERED THE ADIZ.