Narrative:

I flew an IFR flight plan from W29. I was PIC and passenger, an instrument-rated private pilot was communicating with ATC and tuning the radios. With W29 in sight and below the washington/baltimore class B airspace, I told my passenger to cancel IFR. He cancelled the IFR flight plan with potomac approach approximately 7 NM from bay bridge. Potomac approach instructed us to keep our current beacon code for the approach and landing into bay bridge. I conducted a normal visual approach to runway 11 at bay bridge airport. During the approach, while I was scanning the area for traffic and configuring the airplane for landing, it is possible that we inadvertently bumped the 'VFR' button on the #1 transponder, which may have switched the IFR beacon code to the 1200 code. It is also possible that we may have inadvertently switched from the #1 transponder, which contained the IFR beacon code, to the #2 transponder, which was configured with a 1200 code. Both my passenger and I have flown into the washington ADIZ on numerous occasions and are familiar with the procedures that have been in place for the last 2 yrs. In the future, I will certainly be more vigilant to assure that my passenger does not inadvertently change the beacon code, especially when I am operating in the washington ADIZ.

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Original NASA ASRS Text

Title: WHILE APCHING W29, FLT CREW OF PA46 SQUAWK 1200 WITHIN THE DC ADIZ AFTER CANCELING IFR CLRNC.

Narrative: I FLEW AN IFR FLT PLAN FROM W29. I WAS PIC AND PAX, AN INST-RATED PVT PLT WAS COMMUNICATING WITH ATC AND TUNING THE RADIOS. WITH W29 IN SIGHT AND BELOW THE WASHINGTON/BALTIMORE CLASS B AIRSPACE, I TOLD MY PAX TO CANCEL IFR. HE CANCELLED THE IFR FLT PLAN WITH POTOMAC APCH APPROX 7 NM FROM BAY BRIDGE. POTOMAC APCH INSTRUCTED US TO KEEP OUR CURRENT BEACON CODE FOR THE APCH AND LNDG INTO BAY BRIDGE. I CONDUCTED A NORMAL VISUAL APCH TO RWY 11 AT BAY BRIDGE ARPT. DURING THE APCH, WHILE I WAS SCANNING THE AREA FOR TFC AND CONFIGURING THE AIRPLANE FOR LNDG, IT IS POSSIBLE THAT WE INADVERTENTLY BUMPED THE 'VFR' BUTTON ON THE #1 XPONDER, WHICH MAY HAVE SWITCHED THE IFR BEACON CODE TO THE 1200 CODE. IT IS ALSO POSSIBLE THAT WE MAY HAVE INADVERTENTLY SWITCHED FROM THE #1 XPONDER, WHICH CONTAINED THE IFR BEACON CODE, TO THE #2 XPONDER, WHICH WAS CONFIGURED WITH A 1200 CODE. BOTH MY PAX AND I HAVE FLOWN INTO THE WASHINGTON ADIZ ON NUMEROUS OCCASIONS AND ARE FAMILIAR WITH THE PROCS THAT HAVE BEEN IN PLACE FOR THE LAST 2 YRS. IN THE FUTURE, I WILL CERTAINLY BE MORE VIGILANT TO ASSURE THAT MY PAX DOES NOT INADVERTENTLY CHANGE THE BEACON CODE, ESPECIALLY WHEN I AM OPERATING IN THE WASHINGTON ADIZ.

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.