C172 pilot inadvertently squawked VFR after canceling his IFR flight plan within dc ADIZ.

Attributes
ACN	601541
Time
Date	200311
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : jyo.airport
State Reference	VA
Altitude	msl single value : 1500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : pct.tracon
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Route In Use	approach : traffic pattern
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	descent : approach
Route In Use	approach : traffic pattern
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 20 flight time total : 1800 flight time type : 1800
ASRS Report	601541
Events
Anomaly	non adherence : far non adherence : published procedure
Independent Detector	atc equipment other atc equipment : radar other controllera
Resolutory Action	none taken : anomaly accepted other
Consequence	faa : investigated 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 was on an IFR flight plan landing at jyo. Controller told me to switch to unicom frequency when I canceled IFR flight plan but to remain on discrete IFR squawk. Because of distraction with other aircraft in landing pattern and because of training, I inadvertently squawked '1200' which I know was incorrect. Homeland security spoke with me about the incident.

Original NASA ASRS Text

Title: C172 PLT INADVERTENTLY SQUAWKED VFR AFTER CANCELING HIS IFR FLT PLAN WITHIN DC ADIZ.

Narrative: I WAS ON AN IFR FLT PLAN LNDG AT JYO. CTLR TOLD ME TO SWITCH TO UNICOM FREQ WHEN I CANCELED IFR FLT PLAN BUT TO REMAIN ON DISCRETE IFR SQUAWK. BECAUSE OF DISTR WITH OTHER ACFT IN LNDG PATTERN AND BECAUSE OF TRAINING, I INADVERTENTLY SQUAWKED '1200' WHICH I KNOW WAS INCORRECT. HOMELAND SECURITY SPOKE WITH ME ABOUT THE INCIDENT.

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.