What is the primary function of a ship's keel?

What is the primary function of a ship's keel?

• A. To provide structural integrity to resist bending moments and support the hull.
• B. To store ballast water.
• C. To aid in propulsion by housing propeller gear.
• D. To improve hydrodynamic efficiency at high speeds.

Answer: (A)

The keel serves as the ship’s backbone, providing essential longitudinal structural strength. It runs along the bottom from bow to stern and ties together frames, decks, and hull plating, helping the vessel resist bending moments caused by waves and loading. This keeps the hull rigid and maintains its shape under stress. Ballast water is stored in ballast tanks, not in the keel, and propulsion gear is housed in the engine room and shaft system. The keel can aid stability in some designs, but its primary role is to provide structural integrity and keep the hull from bending or twisting.