Radar Observer · ARPA — Errors
ARPA 'target swap' is an error in which:
- AThe radar loses all targets
- BThe tracker transfers its track from one target to another that passes close to it✓ Correct
- CThe display freezes
- DThe range scale changes by itself
Explanation
When two tracked echoes pass close together, the ARPA may swap or merge the tracks, producing a sudden false course/speed for one target. The operator must watch closely during close encounters and not trust the vectors blindly.
Authority: Radar Navigation — ARPA Limitations
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