Garmin GTN 650Xi Series Pilot's Manual page 240

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CREATE AN ATK
From the active flight plan:
1. Select a reference waypoint.
2. Tap Along Track and specify an offset distance.
3. Choose Before or After.
4. Tap Enter.
CREATE AN ATK FOR AN ALTITUDE CONSTRAINT
From the active flight plan:
1. Select an altitude constraint.
2. Tap Along Track and specify an offset distance.
3. Choose Before or After.
4. Tap Enter > Save.
MODIFY AN ATK OFFSET
Once set, offset distances are not editable.
To adjust an existing offset value:
1. Select the ATK from the flight plan.
2. Tap Delete.
3. Create a new ATK with the correct offset distance.
3-98 Pilot's Guide 190-02327-03 Rev. C