A Z-drive is a type of

marine propulsion Marine propulsion is the mechanism or system used to generate thrust to move a watercraft through water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting of an electr ...

unit. Specifically, it is an

azimuth thruster An azimuth thruster is a configuration of marine propellers placed in pods that can be rotated to any horizontal angle (azimuth), making a rudder unnecessary. These give ships better maneuverability than a fixed propeller and rudder system. Ty ...

. 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 A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally air or water). On an aircraft the rudder is used primarily to counter adve ...

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

driveshaft A drive shaft, driveshaft, driving shaft, tailshaft (Australian English), propeller shaft (prop shaft), or Cardan shaft (after Girolamo Cardano) is a component for transmitting mechanical power and torque and rotation, usually used to connec ...

transmission Transmission may refer to: Medicine, science and technology * Power transmission ** Electric power transmission ** Propulsion transmission, technology allowing controlled application of power *** Automatic transmission *** Manual transmission ** ...

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. It does not refer to an electric motor in a rotating pod. The device is different from the Voith-Schneider marine propulsion system (also mechanically linked), which can also quickly change the direction of thrust, as the ''Z-drive'' uses a shrouded conventional

screw A screw and a bolt (see '' Differentiation between bolt and screw'' below) are similar types of fastener typically made of metal and characterized by a helical ridge, called a ''male thread'' (external thread). Screws and bolts are used to ...

that pivots or rotates the propeller, unlike the variable-geometry blades of the Voith-Schneider. Z-drive on Ile de Bréhat

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 GmbH Schottel is a manufacturer of propulsion and steering systems for ships and offshore applications. The company founder Josef Becker invented the rudderpropeller, a z-drive, in 1950. Today the company develops and manufactures azimuth propulsion, ...

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

Types

*Counter-rotating *Integrally installed/hull installation *Deck mounted outboard *Retractable

Origins

Types

Applications

See also

References

External links