PIPER COMANCHE PLT ENTERS CLASS D AIRSPACE WITHOUT CONTACT. CREATES NMAC.

Narrative

I DEPARTED CHINO ARPT TO FLY TO THE COASTLINE FOR A PLEASURE FLT; STAYING BELOW 2000 FT TO CLR SNA CLASS C AREA. I INADVERTENTLY GOT A LITTLE TOO FAR W AND ENCROACHED INTO FUL CLASS D AREA AND DID NOT MAKE RADIO CONTACT WITH THE CTL TWR. A CESSNA WAS ON A LONG STRAIGHT-IN APCH TO RWY; 240 DEGS AT FUL ARPT. I WAS ON A HDG OF APPROX 200 DEGS AND THE CESSNA 240 DEGS. I HAD VISUAL CONTACT WITH THE CESSNA FOR SEVERAL MINS BEFORE XING IN FRONT AND BELOW THE ACFT AND AT NO TIME DID I FEEL THERE WAS ANY PROB. HOWEVER; THE OTHER PLT WAS PROBABLY SHOCKED TO SEE ME PASS IN FRONT OF HIM SINCE FUL CTL TWR HAD CLRED HIM FOR THE LONG STRAIGHT-IN APCH. LATER I WAS ASKED TO CONTACT THE FUL TWR. I TALKED TO THE CTLR AND CESSNA PLT (A FLT INSTRUCTOR) TO EXPLAIN WHAT HAPPENED AND APOLOGIZE FOR NOT HAVING A BETTER KNOWLEDGE OF MY LOCATION WHICH WAS WHY NO RADIO CONTACT WAS MADE WITH THE CTL TWR. LAST EVENING I SPENT SEVERAL HRS GOING OVER THE EVENTS OF THE DAY AND SPENT TIME FAMILIARIZING MYSELF WITH SECTIONAL MAP SYMBOLS AND INFO. MY LACK OF PREPARATION AND NOT HAVING A COURSE FOR THIS FLT; ESPECIALLY IN AN AREA AS CONGESTED AS THE LOS ANGELES BASIN; WAS THE PRIMARY CAUSE OF MY BEING TOO CLOSE TO FUL AND NOT KNOWING. TRUST ME; THIS WILL NEVER HAPPEN AGAIN.