The dead reckoning position is described in relation to which geometric term?

• A. half circle
• B. full circle
• C. line
• D. triangle

Answer: (A)

In dead reckoning, you estimate your new position by traveling a certain distance along a known course from the last fix. On a chart, all the points you could reach after that leg lie at that distance from the last known position, which forms a circle centered on the last fix. Since you’ve moved forward along the course, only the forward half of that circle is possible—the forward semicircle. So the DR position is described by a half circle. The full circle would include positions behind you, which aren’t possible with the given forward direction; a line would imply a single path with no spatial uncertainty; and a triangle doesn’t represent this locus of possible positions.