Narrative:

I was on a night cross country flight from fallbrook (L18) to fullerton, (ful). After takeoff established contact with socal approach for VFR flight following because I would be passing through the santa ana class C. I was cruising at 4500 ft MSL over john wayne airport when approach instructed me to fly heading 270 degrees, so I did. A while after I had passed north of sna, the controller told me that the frequency change (to ful) was approved, and that I should 'resume own navigation to fullerton.' I then changed course and began my descent, and contacted ful, which cleared me into class D. A short while later, the fullerton controller called to ask me what socal had told me, so I told him. He then said that socal had called him, and that they were 'pretty upset' that I had begun to descend. I realized later that I had been in class C without radio contact with socal, since they authorized the frequency change. They never once told me to maintain any specific altitude, nor did they tell me to remain clear of class C. But now I see that even if the controller discontinues radio contact, it is still my responsibility to remain clear of class C, despite the implied permission to cross it during my descent to the destination. However, I know this situation could have been avoided if the controller had merely advised me to 'remain above class C' or 'maintain present altitude.' I will be more careful to ask for explicit permission to cross class C airspace in the future.

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Original NASA ASRS Text

Title: A LOW TIME PVT SMA PLT DSNDS INTO SNA CLASS C AIRSPACE PREMATURELY WHEN CLRED OVER TO FUL TWR. PLT DID NOT REALIZE HE WAS PERFORMING AN UNAUTH PENETRATION OF AIRSPACE.

Narrative: I WAS ON A NIGHT XCOUNTRY FLT FROM FALLBROOK (L18) TO FULLERTON, (FUL). AFTER TKOF ESTABLISHED CONTACT WITH SOCAL APCH FOR VFR FLT FOLLOWING BECAUSE I WOULD BE PASSING THROUGH THE SANTA ANA CLASS C. I WAS CRUISING AT 4500 FT MSL OVER JOHN WAYNE ARPT WHEN APCH INSTRUCTED ME TO FLY HDG 270 DEGS, SO I DID. A WHILE AFTER I HAD PASSED N OF SNA, THE CTLR TOLD ME THAT THE FREQ CHANGE (TO FUL) WAS APPROVED, AND THAT I SHOULD 'RESUME OWN NAV TO FULLERTON.' I THEN CHANGED COURSE AND BEGAN MY DSCNT, AND CONTACTED FUL, WHICH CLRED ME INTO CLASS D. A SHORT WHILE LATER, THE FULLERTON CTLR CALLED TO ASK ME WHAT SOCAL HAD TOLD ME, SO I TOLD HIM. HE THEN SAID THAT SOCAL HAD CALLED HIM, AND THAT THEY WERE 'PRETTY UPSET' THAT I HAD BEGUN TO DSND. I REALIZED LATER THAT I HAD BEEN IN CLASS C WITHOUT RADIO CONTACT WITH SOCAL, SINCE THEY AUTHORIZED THE FREQ CHANGE. THEY NEVER ONCE TOLD ME TO MAINTAIN ANY SPECIFIC ALT, NOR DID THEY TELL ME TO REMAIN CLR OF CLASS C. BUT NOW I SEE THAT EVEN IF THE CTLR DISCONTINUES RADIO CONTACT, IT IS STILL MY RESPONSIBILITY TO REMAIN CLR OF CLASS C, DESPITE THE IMPLIED PERMISSION TO CROSS IT DURING MY DSCNT TO THE DEST. HOWEVER, I KNOW THIS SIT COULD HAVE BEEN AVOIDED IF THE CTLR HAD MERELY ADVISED ME TO 'REMAIN ABOVE CLASS C' OR 'MAINTAIN PRESENT ALT.' I WILL BE MORE CAREFUL TO ASK FOR EXPLICIT PERMISSION TO CROSS CLASS C AIRSPACE IN THE FUTURE.

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.