Scope of Cable
Length of anchor chain veered, expressed as a multiple of water depth (e.g., 6× depth).
In practice
Master orders chain veered (typically 5-7× water depth) on the basis of weather forecast and bottom type. Anchor-watch records the chain veered in the OLB.
Regulatory detail & full definition
Length of anchor chain or wire rope payed out from the hawsepipe, expressed as a multiple of the water depth measured at the hawsepipe. Common scopes are 5–7× water depth in calm conditions, 7–10× in heavy weather. Greater scope produces a flatter chain catenary, transferring less vertical pull on the anchor and increasing holding power; insufficient scope often causes dragging. The relevant equipment number under IACS UR A1 fixes the chain weight and length carried; class regulations on anchor windlass and brake-holding capacity follow.
Related
Source: Standard seamanship
High confidence
Editorial confidence: how we grade.