Narrative:

At approximately the beginning of the last hour of my flight to ttd; salt lake center cleared us direct to our destination. I thanked the controller but told them we were already cleared and going direct to our destination which I verified by looking at the mfd; our flight plan; the magenta needle; and the afcs. The controller said it looked like we were drifting off course but no further mention was made. About 15 minutes later; the controller issued us a heading about 15 degrees to the left of our present heading to fly to our destination. This really confused me although I have had experiences with ATC's radar being wrong or vectors being wrong due to the fact they didn't account for the wind. I told the controller what we were showing wind out of the north at 45 knots which explained in my mind why they say saw us flying north of our destination and issued a vector left. Being perplexed by all this; I zoomed out on the mfd to insure we were flying to our destination which I still showed. I even re-entered ttd into the flight plan with the same results. I was handed off to the next controller and told them we were on a vector but that I now showed us drifting off our direct course to our destination. But this controller confirmed what the other controllers had said. At this point; I knew something was wrong and the controllers really could be right. I closely examined our course. When I had zoomed out previously; the level of detail (other airports; state lines; etc) was very minimal. I began scrolling through the flight plan lines with the cursor which displays the flight plan waypoints in detail on the map. In doing so; I saw that our destination airport waypoint of ttd was actually near R-5701 airspace close to the PDT and hri area. Having flown in that area for years I realized that the controllers were correct the whole time and I was astounded by this error. I tried typing in ttd several more times via different G1000 and prodigy software methods with the same incorrect waypoint results. I typed in pdx which is only about 6 miles west of ttd and sure enough; the vector we were provided was correct. I called the controller and told them we figured out the error could resume our own navigation and thanked them. They then told me they would have a reroute for me (likely due to the actual path being north of what was flown and planned and the mountains). I was given direct hhood; bonvl; then ttd. There were no further abnormalities from there. For sake of experiment after landing and shutdown; I powered the aircraft's electrical system back up and entered ttd waypoint and the database brought up with the correct fix. As best as I could tell; the flight plan waypoint ttd was entered as a user waypoint (orange in color on the garmin/prodigy mfd) during the flight somehow.

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Original NASA ASRS Text

Title: EMB-100 Captain reports entering a direct to TTD (KTTD) in the FMC (G1000) but is informed by ATC that he is not tracking direct. It is discovered that the TTD waypoint is not correctly positioned and alternate means are used to proceed direct. Post flight reveals that possibly a user defined waypoint TTD had been created not located at TTD (airport).

Narrative: At approximately the beginning of the last hour of my flight to TTD; Salt Lake Center cleared us direct to our destination. I thanked the Controller but told them we were already cleared and going direct to our destination which I verified by looking at the MFD; our flight plan; the magenta needle; and the AFCS. The Controller said it looked like we were drifting off course but no further mention was made. About 15 minutes later; the Controller issued us a heading about 15 degrees to the left of our present heading to fly to our destination. This really confused me although I have had experiences with ATC's radar being wrong or vectors being wrong due to the fact they didn't account for the wind. I told the Controller what we were showing wind out of the north at 45 knots which explained in my mind why they say saw us flying north of our destination and issued a vector left. Being perplexed by all this; I zoomed out on the MFD to insure we were flying to our destination which I still showed. I even re-entered TTD into the flight plan with the same results. I was handed off to the next Controller and told them we were on a vector but that I now showed us drifting off our direct course to our destination. But this Controller confirmed what the other controllers had said. At this point; I knew something was wrong and the controllers really could be right. I closely examined our course. When I had zoomed out previously; the level of detail (other airports; state lines; etc) was very minimal. I began scrolling through the flight plan lines with the cursor which displays the flight plan waypoints in detail on the map. In doing so; I saw that our destination airport waypoint of TTD was actually near R-5701 airspace close to the PDT and HRI area. Having flown in that area for years I realized that the controllers were correct the whole time and I was astounded by this error. I tried typing in TTD several more times via different G1000 and Prodigy software methods with the same incorrect waypoint results. I typed in PDX which is only about 6 miles west of TTD and sure enough; the vector we were provided was correct. I called the Controller and told them we figured out the error could resume our own navigation and thanked them. They then told me they would have a reroute for me (likely due to the actual path being north of what was flown and planned and the mountains). I was given direct HHOOD; BONVL; then TTD. There were no further abnormalities from there. For sake of experiment after landing and shutdown; I powered the aircraft's electrical system back up and entered TTD waypoint and the database brought up with the correct fix. As best as I could tell; the flight plan waypoint TTD was entered as a user waypoint (orange in color on the Garmin/Prodigy MFD) during the flight somehow.

Data retrieved from NASA's ASRS site as of July 2013 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.