Narrative:

At approximately XA00, I filed an instrument flight plan for the next day. The flight was to begin at XA00, taking me into an uncontrolled field within the washington/baltimore ADIZ. My clearance included a discrete code and I arrived at my destination airport (gaithersberg, md) at approximately XB30 with vectors for a straight-in approach. As I descended, I broke into clear VFR with a short distance to final. I notified approach and he and he and he turned me loose to land. Since the controller was done with me, I then abandoned the discrete code I had been assigned and squawked 1200. I was about 400 ft above the ground. After landing, I was asked to call approach control on the phone and was told that the rules required me to maintain the discrete code to the ground. I recalled then that the controller had said that when he turned me loose, but for some reason, it didn't register. Perhaps because I often will cancel an IFR clearance, squawk 1200, and land VFR when the landing is assured. As I said, that directive from the approach controller didn't register for some reason, perhaps reflecting the numerous times I have canceled IFR when landing in the clear and having a mind set that this was the same.

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Original NASA ASRS Text

Title: SMA GA PLT DISREGARDS PCT CLRNC AND CTL INSTRUCTIONS TO REMAIN ON DISCRETE CODE WHEN CLRED TO CHANGE FREQ TO LAND AT UNCTLED ARPT IN THE DC ADIZ, REQUIRING A FOLLOW-UP CALL TO PCT TO EXPLAIN ACTION.

Narrative: AT APPROX XA00, I FILED AN INST FLT PLAN FOR THE NEXT DAY. THE FLT WAS TO BEGIN AT XA00, TAKING ME INTO AN UNCTLED FIELD WITHIN THE WASHINGTON/BALTIMORE ADIZ. MY CLRNC INCLUDED A DISCRETE CODE AND I ARRIVED AT MY DEST ARPT (GAITHERSBERG, MD) AT APPROX XB30 WITH VECTORS FOR A STRAIGHT-IN APCH. AS I DSNDED, I BROKE INTO CLR VFR WITH A SHORT DISTANCE TO FINAL. I NOTIFIED APCH AND HE AND HE AND HE TURNED ME LOOSE TO LAND. SINCE THE CTLR WAS DONE WITH ME, I THEN ABANDONED THE DISCRETE CODE I HAD BEEN ASSIGNED AND SQUAWKED 1200. I WAS ABOUT 400 FT ABOVE THE GND. AFTER LNDG, I WAS ASKED TO CALL APCH CTL ON THE PHONE AND WAS TOLD THAT THE RULES REQUIRED ME TO MAINTAIN THE DISCRETE CODE TO THE GND. I RECALLED THEN THAT THE CTLR HAD SAID THAT WHEN HE TURNED ME LOOSE, BUT FOR SOME REASON, IT DIDN'T REGISTER. PERHAPS BECAUSE I OFTEN WILL CANCEL AN IFR CLRNC, SQUAWK 1200, AND LAND VFR WHEN THE LNDG IS ASSURED. AS I SAID, THAT DIRECTIVE FROM THE APCH CTLR DIDN'T REGISTER FOR SOME REASON, PERHAPS REFLECTING THE NUMEROUS TIMES I HAVE CANCELED IFR WHEN LNDG IN THE CLR AND HAVING A MIND SET THAT THIS WAS THE SAME.

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.