Degrees off course vs distance from station
1 degree is 1 NM wide at 60 NM; width scales with distance from the station (PHAK ch.16, Angle of Intercept).
- Degrees off = NM off x 60 / NM from station.
- Example: 3 NM off at 40 NM = 4.5 degrees.
- Same geometry for a VOR radial (CDI) and an NDB bearing (ADF needle).
| Distance from station | 1 degree is (VOR) | 1 NM off track shows (ADF, TP 1102 Station Passage) |
|---|---|---|
| 120 NM | 2 NM wide | - |
| 60 NM | 1 NM wide | about 1 degree |
| 30 NM | 1/2 NM wide | 2 degrees |
| 15 NM | - | 4 degrees |
| 1 NM (abeam) | - | 90 degrees |
- Fixed off-track distance: displacement grows sharply near the station.
Trap: reading NM off as degrees off; a degree widens with distance, so convert with x 60 / NM from station.
References
- TP 1102 Instrument Flying: Station Passage
- FAA-H-8083-25 PHAK ch.16, Angle of Intercept