Stockless Anchor
Most common modern bower anchor type — flukes pivot independently to dig in regardless of orientation.
In practice
The default merchant anchor; held in the hawsepipe by the windlass brake. The chief mate verifies the brake-holding test annually and inspects shank, flukes, and joining shackle at every drydock.
Regulatory detail & full definition
A stockless anchor is the standard anchor of modern merchant ships, in which the flukes pivot on a crown at the end of the shank and there is no stock (the cross-bar of the older Admiralty-pattern anchor). Because it has no stock, the anchor can be hove right up into the hawse pipe and stowed flush against the hull, which is why it displaced the traditional stocked anchor for commercial use. When the anchor is let go the flukes turn and dig into the seabed as the cable is paid out and the pull comes horizontal; holding power depends on fluke area, cable scope and the nature of the bottom.
Authoritative source: IACS Unified Requirements ↗
Related
Source: IACS UR A1 (anchoring equipment); IACS Rec 10
High confidence
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