C172 ENTERS DC ADIZ INADVERTENTLY.

Narrative

I FLEW MY C172 FROM HPN TO TRI; WITH A FUEL STOP AT W45. THERE WERE NO PAX ABOARD THE ACFT. I PHONED BUFFALO FSS FOR WX BRIEFING AROUND XA00 AND DETERMINED THAT THE WX FOR MY FLT WOULD BE VFR AND THAT MY RETURN FLT THE NEXT DAY WAS FEASIBLE. I DID NOT FILE A FLT PLAN. I DO NOT REMEMBER A MENTION OF THE WASHINGTON DC ADIZ DURING THE BRIEFING. WHEN I ASKED THE BRIEFER; HE INDICATED THERE WERE NO TFR'S EXPECTED ALONG MY FLT PATH. NEVERTHELESS; I WAS AWARE OF THE ADIZ. I DEPARTED HPN APPROX XA35 LCL TIME. ON THE FIRST LEG; BTWN HPN AND W45; I INADVERTENTLY FLEW INTO THE ADIZ AIRSPACE NEAR WASHINGTON DC APPROX 3 HRS LATER. I WAS AWARE OF THE ADIZ AND P-40 WHILE PLANNING FOR THE FLT AND DECIDED TO AVOID BOTH INSTEAD OF REQUESTING OR PERFORMING A DIRECT FLT FROM HPN TO W45. MY PLAN WAS TO CONTACT ZNY FOR VFR RADAR SVCS SHORTLY AFTER TKOF SO THAT ATC WOULD BE AWARE OF MY FLT. AS IT TURNS OUT; THE TWR AT HPN ARRANGED FOR FLT FOLLOWING AT TKOF. I FOLLOWED MY CHARTS AND GPS FOR SITUATIONAL AWARENESS WHILE RECEIVING ADVISORIES FROM ATC. WHEN I NEARED WASHINGTON; INSTEAD OF HANDING ME OFF TO THE NEXT CTR; THE CTLR TERMINATED RADAR SVCS AND ADVISED ME TO SQUAWK 1200. I COMPLIED. USUALLY; WHEN A CTLR CANNOT HAND OFF AN ACFT; HE GIVES YOU A FREQ AND SUGGESTS YOU CONTACT THEM YOURSELF IN A FEW MINS. SINCE HE HAD NOT DONE SO; I NEEDED TO FIGURE OUT THE NEXT FREQ MYSELF. I LISTENED ON THE OLD FREQ FOR A WHILE HOPING TO HEAR HIM GIVE THE FREQ TO SOMEONE ELSE; BUT INSTEAD HEARD A DISCUSSION INDICATING THAT WASHINGTON WAS NOT ANSWERING ANOTHER ACFT THAT WAS TRYING TO REACH THEM. I BELIEVE I HEARD FROM CTR WAS; 'THEY AREN'T INTERESTED IN ANSWERING YOU EITHER.' SOON; I LOCATED THE FREQ FOR MYSELF AND PREPARED TO RE-ESTABLISH CONTACT. THE FREQ WAS BUSY WITH ACFT ATTEMPTING TO GET PERMISSION TO ENTER THE ADIZ WITH FLT PLANS. THERE SEEMED TO BE SOME CONFUSION ABOUT WHETHER THE PROC HAD CHANGED. I WAS NOT CONCERNED ABOUT THIS BECAUSE IT WAS MY INTENTION TO CONTACT ATC AND FLY AROUND THE ADIZ. A SHORT TIME BEFORE FINDING A BREAK IN THE RADIO TFC; I NOTICED THAT I WAS CLOSE TO THE WASHINGTON CLASS B AIRSPACE; SO I REDUCED MY ALT TO FLY UNDER THE AIRSPACE. I KNOW THAT I SHOULD HAVE REALIZED THAT I HAD ALREADY PENETRATED THE ADIZ WHEN I WAS CLOSE TO THE CLASS B AIRSPACE. IT SIMPLY DID NOT REGISTER. IT WAS ONLY AFTER I WAS ABLE TO CONTACT APCH CTL TO REQUEST RA'S THAT THEY INFORMED ME THAT I HAD PROBABLY VIOLATED THE AIRSPACE. ALTHOUGH I HAD MADE THE FLT FROM HPN TO TRI ONCE BEFORE AND HAD FLOWN IN THE DC AREA WITH ANOTHER PLT SEVERAL TIMES LAST SUMMER; THIS WAS MY FIRST SOLO FLT ANYWHERE NEAR WASHINGTON. MY GPS DOES NOT SHOW THE ADIZ ON ITS DISPLAY AND MY SECTIONAL DID NOT EITHER. I ASSURE YOU THAT THE INFRACTION WAS INADVERTENT AND I WAS EXTREMELY CAREFUL TO AVOID THE ADIZ ON MY RETURN FLT. I SHOULD HAVE BEEN MORE URGENT IN FINDING THE NEXT ATC FREQ AND REQUESTING RA'S. BUT; I SHOULD NOT HAVE RELIED SO HEAVILY UPON ADVISORIES TO ALERT ME OF THE ADIZ. I SHOULD HAVE MARKED THE EXTENT OF THE AREA ON MY CHARTS PROMINENTLY. TO PREVENT THE PROB IN THE FUTURE; I WILL MORE CAREFULLY PLAN MY FLT AROUND THE ADIZ AND NOT RELY UPON ATC. ANOTHER STEP I SHALL TAKE AS SOON AS POSSIBLE IS TO COMPLETE MY INST RATING TRAINING. IT MIGHT HELP IF THE GPS PROGRAM INDICATES THE ADIZ.