Narrative:

On a VFR flight from new bern, nc, to fayetteville, nc, on V-56, I incorrectly determined the VFR cruising altitude. On the generally westerly heading, I flew at 3500 ft MSL instead of an even altitude in violation of far 91.159. Error was not discovered until I calculated the proper altitude for the return flight and realized I had flown the wrong altitude on the initial flight. Although I was talking to fay approach, no mention of the incorrect altitude was made by them. I am well aware of far 91.159 and have no idea why I calculated the odd +500 ft instead of even +500 ft altitude for a westerly flight. I hope this incident will remind me to be more careful in the future.

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Original NASA ASRS Text

Title: SMA FLYING WBOUND ON THE FAY 102 DEG RADIAL FLEW AT 3500 FT RATHER THAN 4500 FT, THE PROPER ALT FOR A WESTERLY HEADING.

Narrative: ON A VFR FLT FROM NEW BERN, NC, TO FAYETTEVILLE, NC, ON V-56, I INCORRECTLY DETERMINED THE VFR CRUISING ALT. ON THE GENERALLY WESTERLY HEADING, I FLEW AT 3500 FT MSL INSTEAD OF AN EVEN ALT IN VIOLATION OF FAR 91.159. ERROR WAS NOT DISCOVERED UNTIL I CALCULATED THE PROPER ALT FOR THE RETURN FLT AND REALIZED I HAD FLOWN THE WRONG ALT ON THE INITIAL FLT. ALTHOUGH I WAS TALKING TO FAY APCH, NO MENTION OF THE INCORRECT ALT WAS MADE BY THEM. I AM WELL AWARE OF FAR 91.159 AND HAVE NO IDEA WHY I CALCULATED THE ODD +500 FT INSTEAD OF EVEN +500 FT ALT FOR A WESTERLY FLT. I HOPE THIS INCIDENT WILL REMIND ME TO BE MORE CAREFUL IN THE FUTURE.

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.