This article is about the marine propulsion unit. For the common network drive letter, see file server

File server

In computing, a file server is a computer attached to a network that has the primary purpose of providing a location for shared disk access, i.e. shared storage of computer files that can be accessed by the workstations that are attached to the computer network...

.

A Z-drive is a type of marine propulsion

Marine propulsion

Marine propulsion is the mechanism or system used to generate thrust to move a ship or boat across water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting a motor or engine turning a propeller, or less frequently, in jet...

 unit. Specifically, it is an azimuth thruster

Azimuth thruster

An azimuth thruster is a configuration of ship propellers placed in pods that can be rotated in any horizontal direction, making a rudder unnecessary...

. The pod can rotate 360 degrees allowing for rapid changes in thrust direction and thus vessel direction. This eliminates the need for a conventional rudder

Rudder

A rudder is a device used to steer a ship, boat, submarine, hovercraft, aircraft or other conveyance that moves through a medium . On an aircraft the rudder is used primarily to counter adverse yaw and p-factor and is not the primary control used to turn the airplane...

.

The Z-drive is so named because of the appearance (in cross section

Cross section (geometry)

In geometry, a cross-section is the intersection of a figure in 2-dimensional space with a line, or of a body in 3-dimensional space with a plane, etc...

) of the mechanical driveshaft

Driveshaft

A drive shaft, driveshaft, driving shaft, propeller shaft, or Cardan shaft is a mechanical component for transmitting torque and rotation, usually used to connect other components of a drive train that cannot be connected directly because of distance or the need to allow for relative movement...

 or transmission

Transmission (mechanics)

A machine consists of a power source and a power transmission system, which provides controlled application of the power. Merriam-Webster defines transmission as: an assembly of parts including the speed-changing gears and the propeller shaft by which the power is transmitted from an engine to a...

 configuration used to connect the mechanically-supplied driving energy to the Z-Drive azimuth thruster device. This form of power transmission is called a Z-drive because the rotary motion has to make two right angle turns, thus resembling the letter "Z". This name is used to differentiate the arrangement of drive to that of the L-drive

L-drive

An L-drive is a type of azimuth thruster in which the pod-mounted propellers are driven mechanically rather than electrically. Azimuth thruster pods can be rotated through a full 360 degrees, allowing for rapid changes in thrust direction and eliminating the need for a conventional rudder...

. It does not refer to an electric motor in a rotating pod.

The device is different from the Voith-Schneider

Voith-Schneider

The Voith Schneider propeller , also known as a cycloidal drive is a specialized marine propulsion system . It is highly maneuverable, being able to change the direction of its thrust almost instantaneously...

 marine propulsion system (also mechanically linked), which can also quickly change the direction of thrust, as the Z-drive uses a shrouded conventional screw

Screw

A screw, or bolt, is a type of fastener characterized by a helical ridge, known as an external thread or just thread, wrapped around a cylinder. Some screw threads are designed to mate with a complementary thread, known as an internal thread, often in the form of a nut or an object that has the...

 which pivots or rotates or propeller rather than the variable geometry blades of the Voith-Schneider

Voith-Schneider

The Voith Schneider propeller , also known as a cycloidal drive is a specialized marine propulsion system . It is highly maneuverable, being able to change the direction of its thrust almost instantaneously...

.

Origins

The Z-drive transmission was invented in 1950 by Joseph Becker the founder of Schottel and used in the first azimuth thrusters built by Schottel

Schottel

Schottel or Schöttel may refer to:* Ivan Schottel, a United States football coach* Justus Georg Schottel, a Baroque German grammarian* Schottel GmbH, a German manufacturer of marine propulsion equipment- Schöttel : Schottel or Schöttel may refer to:* Ivan Schottel, a United States football coach*...

 in Germany in the 1960s under the Schottel brand name and referred to as Rudderpropeller ever since. Joseph Becker was rewarded with the Elmer A. Sperry Award for this invention as a major contribution to the improvement of transportation worldwide.

Types

• Counter-rotated
• Integrally installed/hull installation
• Deck mounted outboard
• Retractable

Applications

• Floating dredges
• Tank ship
  Tank ship
  A tanker is a ship designed to transport liquids in bulk. Major types of tankship include the oil tanker, the chemical tanker, and the liquefied natural gas carrier.-Background:...
  
  
• Coastal trading vessel
  Coastal trading vessel
  Coastal trading vessels, also known as coasters, are shallow-hulled ships used for trade between locations on the same island or continent. Their shallow hulls mean that they can get through reefs where deeper-hulled sea-going ships usually cannot....
  
   (coasters)
• Platform supply vessel
  Platform supply vessel
  A Platform supply vessel is a ship specially designed to supply offshore oil platforms. These ships range from 20 to 100 meters in length and accomplish a variety of tasks...
  
  
• Passenger ship
  Passenger ship
  A passenger ship is a ship whose primary function is to carry passengers. The category does not include cargo vessels which have accommodations for limited numbers of passengers, such as the ubiquitous twelve-passenger freighters once common on the seas in which the transport of passengers is...
  
  
• Ferry
  Ferry
  A ferry is a form of transportation, usually a boat, but sometimes a ship, used to carry primarily passengers, and sometimes vehicles and cargo as well, across a body of water. Most ferries operate on regular, frequent, return services...
  
  
• Trawler
  Trawler
  A fishing trawler is a commercial fishing vessel designed to operate fishing trawls. Trawling is a method of fishing that involves actively dragging or pulling a trawl through the water behind one or more trawlers. Trawls are fishing nets that are pulled along the bottom of the sea or in midwater...
  
   and Fishing trawler
• Cargo ship
  Cargo ship
  A cargo ship or freighter is any sort of ship or vessel that carries cargo, goods, and materials from one port to another. Thousands of cargo carriers ply the world's seas and oceans each year; they handle the bulk of international trade...
  
  
• Self-sailing pontoons
• Barge
  Barge
  A barge is a flat-bottomed boat, built mainly for river and canal transport of heavy goods. Some barges are not self-propelled and need to be towed by tugboats or pushed by towboats...
  
  
• Yacht
  Yacht
  A yacht is a recreational boat or ship. The term originated from the Dutch Jacht meaning "hunt". It was originally defined as a light fast sailing vessel used by the Dutch navy to pursue pirates and other transgressors around and into the shallow waters of the Low Countries...
  
  
• Tug
  Tug
  Tuğ is a village in the Khojavend Rayon of Azerbaijan....
  
  s

See also

• Azipod
  Azipod
  Azipod is the registered brand name of the ABB Group for their azimuth thruster. Originally developed in Finland jointly by Kvaerner Masa-Yards dockyards and ABB, these are marine propulsion units consisting of electrically driven propellers mounted on a steerable pod.The pod's propeller usually...
  
  
• Saildrive
  Saildrive
  A saildrive is a transmission system for a boat whose inboard engine has a horizontal output shaft. The saildrive's input shaft is therefore also horizontal. That input shaft is geared so as to drive a vertical intermediate shaft extending downward through the hull...
  
  , a Z-drive with fixed azimuth, for sailboats
• Propulsor
  Propulsor
  A propulsor is a mechanical device that gives propulsion. The word is commonly used in the marine vernacular, and implies a mechanical assembly that is more complicated than a propeller. The Kort nozzle and Pump-jet are examples....
  
  
• Voith Schneider Propeller
• L-drive
  L-drive
  An L-drive is a type of azimuth thruster in which the pod-mounted propellers are driven mechanically rather than electrically. Azimuth thruster pods can be rotated through a full 360 degrees, allowing for rapid changes in thrust direction and eliminating the need for a conventional rudder...
  
  
• Kort nozzle
  Kort nozzle
  The Kort nozzle is a shrouded, ducted propeller assembly for marine propulsion. The hydrodynamic design of the shroud, which is shaped like a foil, offers advantages for certain conditions over bare propellers....