Narrative:

Sunday, departed auh, climbed to 6500 ft, contacting ZMP for VFR flight following. Correct altitude should have been odd +500 ft. Continued on course (heading to bqs VOR) but canceled flight following and landed at falls city, northeast, because of haze and deteriorating visibility (were above VFR minimums at 7 mi). After waiting 2 hours for better visibility, again departed and climbed to 6500 ft, got flight following from ZKC, and continued flight following until descent into osage beach/grand glaize. I did not realize my error in chosen altitude until several hours after the flight, while reviewing the sectional for another trip. I have no explanation for my stupidity, and can honestly say I have never made this error before. With all the different controllers I spoke with that day, at no time did there appear to be a conflict with other traffic, fortunately. No one ever questioned my choice of altitude. I can think of no contributing factors, just a stupid mistake.

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Original NASA ASRS Text

Title: ALT HDG RULE VIOLATED BY A LOW TIME PVT PA28 PLT ON A VFR FLT ON FREQ WITH ZMP, MN.

Narrative: SUNDAY, DEPARTED AUH, CLBED TO 6500 FT, CONTACTING ZMP FOR VFR FLT FOLLOWING. CORRECT ALT SHOULD HAVE BEEN ODD +500 FT. CONTINUED ON COURSE (HDG TO BQS VOR) BUT CANCELED FLT FOLLOWING AND LANDED AT FALLS CITY, NE, BECAUSE OF HAZE AND DETERIORATING VISIBILITY (WERE ABOVE VFR MINIMUMS AT 7 MI). AFTER WAITING 2 HRS FOR BETTER VISIBILITY, AGAIN DEPARTED AND CLBED TO 6500 FT, GOT FLT FOLLOWING FROM ZKC, AND CONTINUED FLT FOLLOWING UNTIL DSCNT INTO OSAGE BEACH/GRAND GLAIZE. I DID NOT REALIZE MY ERROR IN CHOSEN ALT UNTIL SEVERAL HRS AFTER THE FLT, WHILE REVIEWING THE SECTIONAL FOR ANOTHER TRIP. I HAVE NO EXPLANATION FOR MY STUPIDITY, AND CAN HONESTLY SAY I HAVE NEVER MADE THIS ERROR BEFORE. WITH ALL THE DIFFERENT CTLRS I SPOKE WITH THAT DAY, AT NO TIME DID THERE APPEAR TO BE A CONFLICT WITH OTHER TFC, FORTUNATELY. NO ONE EVER QUESTIONED MY CHOICE OF ALT. I CAN THINK OF NO CONTRIBUTING FACTORS, JUST A STUPID MISTAKE.

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.