Which statement correctly describes a planing hull?

Which statement correctly describes a planing hull?

• A. Displaces water at rest
• B. Remains submerged below water
• C. At certain speeds, the hull will skim along the surface of the water.
• D. Uses ballast to stabilize

Answer: (C)

A planing hull is designed to lift up and ride on the water’s surface as speed increases. When enough speed is reached, the hull’s shape and the flow of water generate dynamic lift, so most of the hull is out of the water and the boat skimmed along the surface. This greatly reduces the drag compared with a hull that stays down in the water, which is why planing hulls are used for high-speed boats. The other descriptions don’t fit because staying submerged or displacing water at rest describes a different hull type, and ballast is about weight balance rather than the fundamental way a planing hull interacts with the water.

A planing hull is designed to lift up and ride on the water’s surface as speed increases. When enough speed is reached, the hull’s shape and the flow of water generate dynamic lift, so most of the hull is out of the water and the boat skimmed along the surface. This greatly reduces the drag compared with a hull that stays down in the water, which is why planing hulls are used for high-speed boats. The other descriptions don’t fit because staying submerged or displacing water at rest describes a different hull type, and ballast is about weight balance rather than the fundamental way a planing hull interacts with the water.