Narrative:

IFR flight plan pwk to bfa. Cleared to descend to 3500 ft by ZMP. Broke out at 3500 ft 10 mi from the airport. Then cleared for a visual and canceled my GPS approach. Declared that I had the field in sight. The controller then instructed me to change frequency to CTAF, which I did thinking he was canceling my IFR flight plan. Wrong! Because I did not use the magic word 'cancel.' center then had to check with the airport manager to be sure I had landed safely. Do not frequently fly IFR into uncontrolled airports, so slipped this time. Should have remembered, as I will in the future, to use the word 'cancel.

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Original NASA ASRS Text

Title: C421 PLT FORGOT TO CLOSE HIS IFR FLT PLAN AFTER LNDG AT A NON TWR ARPT DUE TO THE HABIT OF HAVING AUTOMATIC FLT PLAN CLOSURE WHEN LNDG AT CTLED ARPTS.

Narrative: IFR FLT PLAN PWK TO BFA. CLRED TO DSND TO 3500 FT BY ZMP. BROKE OUT AT 3500 FT 10 MI FROM THE ARPT. THEN CLRED FOR A VISUAL AND CANCELED MY GPS APCH. DECLARED THAT I HAD THE FIELD IN SIGHT. THE CTLR THEN INSTRUCTED ME TO CHANGE FREQ TO CTAF, WHICH I DID THINKING HE WAS CANCELING MY IFR FLT PLAN. WRONG! BECAUSE I DID NOT USE THE MAGIC WORD 'CANCEL.' CTR THEN HAD TO CHK WITH THE ARPT MGR TO BE SURE I HAD LANDED SAFELY. DO NOT FREQUENTLY FLY IFR INTO UNCTLED ARPTS, SO SLIPPED THIS TIME. SHOULD HAVE REMEMBERED, AS I WILL IN THE FUTURE, TO USE THE WORD 'CANCEL.

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.