A tunnel hull is a type of boat hull that uses two typically planing hulls with a solid center that traps air. This entrapment then creates aerodynamic lift in addition to the planing (hydrodynamic) lift from the hulls. Many times this is attributed to ground effect

Ground effect

As it pertains to fixed wing aircraft, "ground effect" refers to the increased lift and decreased drag that an aircraft airfoil or wing generates when an aircraft is about one wingspan's length or less over the ground...

. Theoretical research and full-scale testing of tunnel hulls has demonstrated the dramatic contributions of 'close-proximity ground effect' on enhanced aerodynamic lift/drag in operation of performance tunnel hull designs.

Tunnel hulls are distinguishable from other catamaran

Catamaran

A catamaran is a type of multihulled boat or ship consisting of two hulls, or vakas, joined by some structure, the most basic being a frame, formed of akas...

s by the typical close hull spacing and solid deck in between the hulls.

Formula 1 powerboats have a tunnel hull catamaran design allowing them to go faster. Tunnel hulls are a common design in offshore powerboat racing

Offshore powerboat racing

Offshore powerboat racing is racing by large, specially designed ocean-going powerboats, typically point-to-point racing.Probably one of the largest, most dangerous, and most powerful racing machines of all, the extreme expense of the boats and the fuel required to participate make it an expensive...

.

See also

• Cathedral hull
  Cathedral hull
  A cathedral hull is a hull shape used in modern boats, usually power-driven. It can be thought of as a kind of vestigial trimaran in which the center hull has two smaller side hulls which are so close to the main hull that there is no longer any open space. In fact a cathedral hull is a...
  
  
• Hickman sea sled
  Hickman sea sled
  The Hickman Sea Sled is an inverted vee planing hull invented by Albert Hickman. The Sea Sled is a direct forefather of the modern high speed catamaran or tunnel hull....
  
  
• Boston Whaler
  Boston Whaler
  Boston Whaler is a boat company that builds foam filled fiberglass boats. Boston whaler was founded in 1958 by Richard T Fisher, and is still in business today.-History of the Design:...
  
  
• Supercavitation propeller
• Offshore Powerboat Racing
  Offshore powerboat racing
  Offshore powerboat racing is racing by large, specially designed ocean-going powerboats, typically point-to-point racing.Probably one of the largest, most dangerous, and most powerful racing machines of all, the extreme expense of the boats and the fuel required to participate make it an expensive...