kølængder

Kölängder, or keel lengths, refer to the length of the keel, the major structural element that runs along the bottom of a boat or ship from bow to stern. The term is used in ship design, construction, and sailing discussions to describe how much of the hull’s underside is occupied by the keel and how long that underwater appendage extends.

The keel serves several functions. It provides structural rigidity by acting as a backbone for the hull, houses ballast in certain designs to lower the center of gravity, and contributes to stability and directional control. The length of the keel influences hydrodynamic performance, draft, and the vessel’s righting moment. A longer keel generally offers greater directional stability and straight-line tracking, while a shorter or fin keel can improve maneuverability and speed but may reduce stability if not adequately ballast or shaped.

Keels come in a variety of types, and the length is chosen in relation to hull form and intended use. Traditional sailing vessels often employ long or full keels that run close to or along much of the hull’s length. Modern yachts may use shorter fin keels, wing keels, or retractable lifting keels, each with different implications for draft, ballast distribution, and performance.

In design documentation, specifications for kölängder are presented alongside other dimensions such as overall length, beam, and draft. Variations in keel length reflect trade-offs among stability, seaworthiness, speed, and market segment, from cruising to racing applications.