Pilot of M20 squawks 1200 within dc ADIZ.

Attributes
ACN	636933
Time
Date	200411
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : gai.airport
State Reference	MD
Altitude	msl bound lower : 8000 msl bound upper : 9000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : pct.tracon
Operator	general aviation : personal
Make Model Name	M-20 J (201)
Operating Under FAR Part	Part 91
Flight Phase	descent : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 43 flight time total : 2000 flight time type : 1550
ASRS Report	636933
Person 2
Affiliation	government : faa
Function	controller : approach
Events
Anomaly	non adherence : far non adherence : published procedure non adherence : clearance
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance Airspace Structure
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I obtained a computerized briefing via duats and filed an IFR flight plan for gaithersburg, md. I took off from 1d2 (plymouth, mi), and activated this plan with detroit approach control. While approaching the martinsberg VOR, I asked to cancel IFR and proceed VFR direct to gaithersburg. I was told to remain on current heading to martinsberg while the controller checked on military operation status in the ADIZ. A few moments later, the controller said the request was granted, and I said I would retain the current transponder code for further advisories. I began a VFR descent at this time. Somewhere near, or shortly past martinsberg, I started concentrating more closely on local navigation, as I had not been to this airport for approximately 4 yrs. To minimize the distrs for the last phase of the flight, among other preparations, I switched the transponder to 1200, mostly based on force of habit. I later switched to gaitherburg CTAF, obtained the necessary information, and landed without incident. I was met by a worker at gaithersburg, who told me that I was to call TRACON as soon as possible. I did so, and at that time, first learned of my error in procedure.

Original NASA ASRS Text

Title: PLT OF M20 SQUAWKS 1200 WITHIN DC ADIZ.

Narrative: I OBTAINED A COMPUTERIZED BRIEFING VIA DUATS AND FILED AN IFR FLT PLAN FOR GAITHERSBURG, MD. I TOOK OFF FROM 1D2 (PLYMOUTH, MI), AND ACTIVATED THIS PLAN WITH DETROIT APCH CTL. WHILE APCHING THE MARTINSBERG VOR, I ASKED TO CANCEL IFR AND PROCEED VFR DIRECT TO GAITHERSBURG. I WAS TOLD TO REMAIN ON CURRENT HDG TO MARTINSBERG WHILE THE CTLR CHKED ON MIL OP STATUS IN THE ADIZ. A FEW MOMENTS LATER, THE CTLR SAID THE REQUEST WAS GRANTED, AND I SAID I WOULD RETAIN THE CURRENT XPONDER CODE FOR FURTHER ADVISORIES. I BEGAN A VFR DSCNT AT THIS TIME. SOMEWHERE NEAR, OR SHORTLY PAST MARTINSBERG, I STARTED CONCENTRATING MORE CLOSELY ON LCL NAV, AS I HAD NOT BEEN TO THIS ARPT FOR APPROX 4 YRS. TO MINIMIZE THE DISTRS FOR THE LAST PHASE OF THE FLT, AMONG OTHER PREPARATIONS, I SWITCHED THE XPONDER TO 1200, MOSTLY BASED ON FORCE OF HABIT. I LATER SWITCHED TO GAITHERBURG CTAF, OBTAINED THE NECESSARY INFO, AND LANDED WITHOUT INCIDENT. I WAS MET BY A WORKER AT GAITHERSBURG, WHO TOLD ME THAT I WAS TO CALL TRACON AS SOON AS POSSIBLE. I DID SO, AND AT THAT TIME, FIRST LEARNED OF MY ERROR IN PROC.

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.