Narrative:

Part 91 corporate flight back to western washington over the cascade mountains. Daylight departure; night arrival into MVFR/IFR conditions after a VMC descent into the terminal/approach area. Cleared direct to the IAF for an RNAV approach at destination; a transition and approach I have flown a couple dozen times in training and operationally. Entered IMC conditions with light icing and light turbulence just prior to the IAF. Was given a crossing restriction at the IAF and cleared for the approach; after passing the fix; noticed my position on my ipad depicted me well north of the desired transition course and deviating. As I started the turn to the right (east) to correct; noticed that I had misprogrammed the GPS (GNS 480) where the approach wasn't 'executed'. The GPS steering had me going to the airport rather than the next if on the approach. As I attempted to reload and activate the approach while correcting back on course; broke out into night; visual conditions; announced as much to approach while requesting the visual and cancelled IFR. Landed uneventfully. (Approach never mentioned deviation and there was never any threat to terrain or other aircraft.) lessons: don't take a milk run back to home base for granted. Light icing; rain and turbulence surprised me; as metar and local tafs showed only broken layers and good vis. I had a good plan for the approach; but executed it very poorly; specifically with regards to GPS programming and confirmation of 'what is it doing next?' I have been flying several different type aircraft lately with different avionics and have to believe this contributed to my complacency and error. One of the dirty secrets of aviation is fatigue. I had brought these passengers out early that morning and sat all day at destination waiting for them. Of course they were well past the proposed departure time. Lesson: even though the schedule isn't known; you must grab some rest if you need it; especially with a return to IMC conditions and/or if you are fatigued. I definitely was tired looking back on the flight on the drive home. I had a supremely capable airplane; flying a well-known route and approach to my home airport; and I made a couple errors that could have compounded into something more serious like an official deviation or worse. Great lesson and won't happen again anytime soon.

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Original NASA ASRS Text

Title: Pilot became disoriented during an instrument approach in IMC conditions. Pilot discovered the track error by noticing his previous error while programming his iPad for the approach. Pilot reprogrammed the approach and landed safely in VMC.

Narrative: Part 91 corporate flight back to western Washington over the Cascade Mountains. Daylight departure; night arrival into MVFR/IFR conditions after a VMC descent into the terminal/approach area. Cleared direct to the IAF for an RNAV approach at destination; a transition and approach I have flown a couple dozen times in training and operationally. Entered IMC conditions with light icing and light turbulence just prior to the IAF. Was given a crossing restriction at the IAF and cleared for the approach; after passing the fix; noticed my position on my iPad depicted me well north of the desired transition course and deviating. As I started the turn to the right (east) to correct; noticed that I had misprogrammed the GPS (GNS 480) where the approach wasn't 'executed'. The GPS steering had me going to the airport rather than the next IF on the approach. As I attempted to reload and activate the approach while correcting back on course; broke out into night; visual conditions; announced as much to approach while requesting the visual and cancelled IFR. Landed uneventfully. (Approach never mentioned deviation and there was never any threat to terrain or other aircraft.) Lessons: don't take a milk run back to home base for granted. Light icing; rain and turbulence surprised me; as METAR and local TAFs showed only BKN layers and good vis. I had a good plan for the approach; but executed it very poorly; specifically with regards to GPS programming and confirmation of 'what is it doing next?' I have been flying several different type aircraft lately with different avionics and have to believe this contributed to my complacency and error. One of the dirty secrets of aviation is fatigue. I had brought these passengers out early that morning and sat all day at destination waiting for them. Of course they were well past the proposed departure time. Lesson: even though the schedule isn't known; you MUST grab some rest if you need it; especially with a return to IMC conditions and/or if you are fatigued. I definitely was tired looking back on the flight on the drive home. I had a supremely capable airplane; flying a well-known route and approach to my home airport; and I made a couple errors that could have compounded into something more serious like an official deviation or worse. Great lesson and won't happen again anytime soon.

Data retrieved from NASA's ASRS site 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.