Master the Navigation, Seamanship, and Shiphandling (NSS) – Officer of the Deck (OOD) Phase 2 Exam with engaging flashcards and multiple choice questions, complete with hints and explanations. Prepare comprehensively for your test!

Multiple Choice

Which horizontal datum is used on nautical charts?

Horizontal datum is the reference model that tells you where coordinates on a chart actually sit on the Earth. For nautical charts, the standard global reference used is WGS-84 because it aligns with GPS data and is adopted across modern charts to keep fixes and chart positions consistent worldwide. Using WGS-84 ensures that a position derived from GNSS matches the charted position without offsets. Other options like NAD83, ETRS89, or ED50 are regional or older datums and can introduce mismatches if used instead of the global standard.

Horizontal datum is the reference model that tells you where coordinates on a chart actually sit on the Earth. For nautical charts, the standard global reference used is WGS-84 because it aligns with GPS data and is adopted across modern charts to keep fixes and chart positions consistent worldwide. Using WGS-84 ensures that a position derived from GNSS matches the charted position without offsets. Other options like NAD83, ETRS89, or ED50 are regional or older datums and can introduce mismatches if used instead of the global standard.