OTH Boat Crew Practice Test

Anchor scope is the length of rode needed relative to water depth, and it directly affects how the anchor pulls and holds. For moderate weather, using a scope of about three to five times the water depth gives enough rode to let the anchor set firmly and to absorb the energy from wind and current without overloading the line. A longer scope reduces the angle of pull on the anchor, which increases holding power and helps prevent dragging during surge. If you drop the scope too short, like one to two times the depth, the pull on the anchor becomes steeper and the holding tendency drops, making dragging more likely even in light conditions. Conversely, as conditions worsen, you’d increase the scope—about five to seven to one for heavier weather, and seven to nine to one for extreme weather—to maintain secure holding.