Narrative:

Departed rmg VFR for cha (approximately 40 mi north). Navigating GPS direct. Shortly after takeoff, received IFR clearance direct. While climbing to assigned altitude (4000 ft), I selected VOR runway 33 approach at cha with IAF of D090G for the DME arc. The GPS dutifully loaded all the approach fixes into the route being flown. After leveling at 4000 ft, a couple of mins later, center asked if I was proceeding direct. I realized I was proceeding direct to the IAF which is about 12 mi east of cha. I confessed this to center and he amended my clearance to proceed on my current heading. Since installing the IFR approved GPS, I always file (and am almost always cleared) airport to airport direct. I obviously shouldn't select an approach in the GPS if I am using it for my primary navigation, until receiving an appropriate clearance (from an appropriate facility). In the future, I will file airport to an IAF for the destination airport.

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Original NASA ASRS Text

Title: SINGLE PLT IFR REPROGRAMS HIS GPS WHILE CLBING. HAD BEEN CLRED DIRECT FROM RMG TO CHA, GA. THE NEWLY PROGRAMMED POINT WAS AN IAF ON A DME ARC. PLT FORGOT THAT THE HE WOULD BE NAVING TOWARDS THAT FIX, WHICH WAS ENRTE TO DEST POINT.

Narrative: DEPARTED RMG VFR FOR CHA (APPROX 40 MI N). NAVING GPS DIRECT. SHORTLY AFTER TKOF, RECEIVED IFR CLRNC DIRECT. WHILE CLBING TO ASSIGNED ALT (4000 FT), I SELECTED VOR RWY 33 APCH AT CHA WITH IAF OF D090G FOR THE DME ARC. THE GPS DUTIFULLY LOADED ALL THE APCH FIXES INTO THE RTE BEING FLOWN. AFTER LEVELING AT 4000 FT, A COUPLE OF MINS LATER, CTR ASKED IF I WAS PROCEEDING DIRECT. I REALIZED I WAS PROCEEDING DIRECT TO THE IAF WHICH IS ABOUT 12 MI E OF CHA. I CONFESSED THIS TO CTR AND HE AMENDED MY CLRNC TO PROCEED ON MY CURRENT HDG. SINCE INSTALLING THE IFR APPROVED GPS, I ALWAYS FILE (AND AM ALMOST ALWAYS CLRED) ARPT TO ARPT DIRECT. I OBVIOUSLY SHOULDN'T SELECT AN APCH IN THE GPS IF I AM USING IT FOR MY PRIMARY NAV, UNTIL RECEIVING AN APPROPRIATE CLRNC (FROM AN APPROPRIATE FACILITY). IN THE FUTURE, I WILL FILE ARPT TO AN IAF FOR THE DEST ARPT.

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.