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Navigation & chartwork

What is the difference between a DR position and an EP?

Short answer

EP includes tidal stream and leeway; DR does not

A DR advances movement through the water from the accepted start. An EP adds estimated leeway and tidal stream, so it may be more useful but is still only as sound as its inputs. Revise Dead Reckoning and Estimated Position.

Sources and scope

Reviewed by Richard Moore on . This answer is scoped to united kingdom and general recreational seamanship; check the current chart, publication, local rules and official operational guidance before acting afloat.

Quick check

What is the difference between a DR position and an EP?