Navigation General · Electronic Nav — GPS Error Sources
Which of the following is a normal source of GPS position error?
- AHull paint color
- BEngine vibration
- CCompass deviation
- DIonospheric/tropospheric signal delay, multipath, and poor satellite geometry✓ Correct
Explanation
GPS accuracy is degraded by atmospheric (ionospheric/tropospheric) signal delays, multipath reflections near structures, satellite clock/ephemeris errors, and weak geometry (high HDOP/GDOP) when satellites are clustered. These are reduced by augmentation systems.
Authority: Bowditch
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