Radar Observer · Navigation — Range vs Bearing Accuracy
For a radar position fix, ranges are generally preferred over bearings because:
- ABearings cannot be measured at all
- BRadar range measurement is far more accurate than radar bearing, which is degraded by beam width✓ Correct
- CRanges require no calibration
- DBearings are only available on ARPA
Explanation
Radar measures range very accurately (timing), but bearing is limited by horizontal beam width (a target is painted across the whole beam), so radar bearings carry more error. A fix from two or three radar ranges to identified objects is therefore stronger than one from radar bearings; if a bearing must be used, take it to a small, sharply defined object.
Authority: Bowditch (Pub. No. 9), Radar Navigation
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