SafeFly GPS lateral offset error

[YellowJacket RV9]

Was looking around tonight at my ForeFlight track logs and noticed something odd. Ever since I installed an echouat unit with the GRT SafeFly 2020 GPS, all my track logs have been offset about 100’ roughly ESE of my actual track. It’s only noticeable when overlaid on the ForeFlight taxi and runway diagrams, but it is very consistent. It did not occur when I was using an XGPS150 paired to the iPad.

Initial thought was that I had accidentally programmed a lateral installation offset into the unit, but the direction of that error would change with aircraft heading. My error does not.

Seeing as this is a WAAS unit and supposedly 2020 approved, this amount of error is concerning, but since it is so consistent there’s gotta be a simple cause. I will email GRT tomorrow but was wondering if I am the first to see this.

Chris

[KRviator]

Originally Posted by YellowJacket RV9

Was looking around tonight at my ForeFlight track logs and noticed something odd. Ever since I installed an echouat unit with the GRT SafeFly 2020 GPS, all my track logs have been offset about 100? roughly ESE of my actual track. It?s only noticeable when overlaid on the ForeFlight taxi and runway diagrams, but it is very consistent. It did not occur when I was using an XGPS150 paired to the iPad.

Seeing as this is a WAAS unit and supposedly 2020 approved, this amount of error is concerning, but since it is so consistent there?s gotta be a simple cause. I will email GRT tomorrow but was wondering if I am the first to see this.

Given you've said it's a consistent 100' ESE deviation sounds like there is a datum mismatch between your logs, and what ForeFlight is displaying. Is there scope to change the datum in Foreflight for any imported logs?