top of page


The Autonav medium pressure rotary vane is a compact, simple and mechanically efficient rudder actuator. Field proven performance and reliability confirm its suitability for all types of commercial and naval vessels. The Autonav rotary vane steering gears were designed in cooperation with the National Research Council of Canada and meet the requirements of classification authorities worldwide.

Features of the Rotary Vane:

  • Automatic actuator isolation

  • Volumetric efficiency is maximized

  • Mechanical efficiency exceeds 90%

  • The seals are long life and low friction

  • Radial and carrier bearings are integral and self-lubricating

  • Easy Chockfast© mountings provide self-alignment and eliminate fitted bolts

  • Rudder positioning accuracy exceeds 0.2%

  • Second-generation long-life, low-leakage seals eliminate problems associated with older designs

  • The totally enclosed oil-filled actuator is corrosion proof

  • The Autonav Rotary Vane was chosen for Service in the Canadian Naval Frigates

  • Withstand in excess of 100 G shock

  • 20 dB quieter than U.S. Naval specifications

  • 235% more reliable than Ram systems with 9.3% of the maintenance

Rugged System Design

The simple, rugged design has only one moving part.

The long-life dynamic seals with our unique design, are tolerant of contamination and wear, ensuring minimal internal leakage and trouble-free operation. All protective valving are external, eliminating the need to disassemble the unit for servicing.


Autonav rotary vane steering gears have a higher operating pressure (10,000 kPa or 1450 psi) than most other units and are more compact. Autonav’s unique seal and bearing materials have a proven life in excess of 70,000 hours with ZERO measurable wear.

Built-in Features

Newer technology, such as Variable Frequency Drives (VFD), provides very fast and accurate rudder speeds with continuously variable acceleration and deceleration for smooth and accurate rudder positioning. VFD greatly reduces component wear and maintenance while eliminating heat generation and space and weight constraints due to a more compact and lighter weight system.

A self-lubricating rudder carrier and radial bearings are incorporated in the Autonav rotary vane steering gear. Torque is balanced, as the operating pressure is equal in symmetrically located chambers. Integral rudder stops are also featured. Rudder angles up to 2 x 70 degrees* are available.

Precise and Dependable

The Autonav rotary vane steering gear provides precise, dependable rudder response in all sea conditions. Control systems available include hydraulic or electric (full follow-up), electric time-dependent (non follow-up) and even simple manual hydraulics. 

They are selected according to the customer's requirements and the operating demands of the vessel. Standardized Autonav components permit custom control packages to be assembled at minimal expense.

* Depending on actuator model

bottom of page