Crossing LOBs will generate an ellipse which can be used in the LKP scenario to drift.

• A. False
• B. True
• C. Not applicable
• D. It forms a circle

Answer: (B)

Crossing lines of bearing from different observers gives a likely area for the target, not a single exact point, because each bearing has measurement error and the target may have drifted since the last sighting. When you combine those uncertainties, the probable location becomes a two‑dimensional region rather than a point. In the Last Known Position (LKP) drift scenario, that region is commonly modeled as an ellipse: the center near where the bearings intersect, a major axis aligned with the predominant drift direction (current or wind), and a length that reflects how far the target could have moved. This elliptical shape captures both directional drift and measurement uncertainty, making it a practical guide for where to search first. A circle wouldn’t reflect the directional bias introduced by drift, so the ellipse is the more accurate representation for planning the search.