Open Moor
Two anchors set with cables forming a wide V to limit swing in restricted anchorage.
In practice
Used when wind/sea is forecast in one dominant direction. Two chains form a wide V; deck crew tend the bridle.
Regulatory detail & full definition
Anchoring procedure laying two anchors with their chains forming a wide V from the bow, providing greater holding power against a single dominant force direction (e.g. heavy onshore wind) and reducing yaw. The approach uses a typical anchor-spread angle of 30–45° between chains. Open moor is used when single-anchor holding is inadequate but full Bahamian moor is unnecessary. Equipment number requirements may demand both bow anchors carry chain of equal grade. Master selects single-anchor, open moor, or Bahamian moor based on weather forecast and water depth.
Related
Source: Standard seamanship
High confidence
Editorial confidence: how we grade.