OPERATING QUALITIES OF TWIN-RUDDER MOTORSHIPS OF THE VOLGO-BALT CLASS

The propellers of cargo motorships of the 791 design in the Volgo-Balt class are equipped with shaft guide extensions and a central twin rudder represented by two fins measuring 3 sq. m. in area each of which are linked by a cast crossbeam attached to the rudder stock. The twin rudder and the shaft extensions are synchronously turned by the same steering mechanism. The steering gear of ships of this kind consists of two shaft extensions, a central twin rudder, an electrohydraulic steering mechanism, an oil line and an electrical control system. Operating trials of ships of this kind during the 1967 navigation season revealed that the installation of a central twin rudder markedly increased their maneuverability during travel at minimum stable r.p.m. as well as during travel by inertia, which is particularly important in canal navigation as well as when maneuvering the ship toward the lock chambers. The expediency of equipping ships with the twin rudder depends on the particular conditions of navigation. For ships which chiefly travel along canals with a lock system (the White Sea-Baltic and Volga-Baltic canals) twin rudders will be undoubtedly useful. For ships traveling under more favorable conditions the installation of the twin rudder is not obligatory. To improve the maneuverability of twin-rudder-equipped motorships (during travel by inertia) the stabilizer fins of shaft extensions, which have been removed during the modernization of these ships, should best be reinstalled and, insofar as possible, their area should be enlarged by modifying their configuration. Improvements in the design and an increase in the area of the additional central rudder as well as adjusting its angle of deflection so that it exceeds by a factor of 2.5-3 the angle of deflection of the propeller shaft extensions make it possible to commensurately reduce the losses of traveling speed and markedly improve the maneuverability indicators and also to assure more reliable maneuverability during travel by inertia.

• Authors:
  • Yevlashev, A
• Publication Date: 1968

Media Info

• Features: Figures; Tables;
• Pagination: p. 28-30
• Serial:
  • Rechnoy Transport
  • Issue Number: 8

Subject/Index Terms

• TRT Terms: Canal operations; Canals; Maneuverability; Rudders; Ship pilotage; Steering gears
• Old TRIS Terms: Twin rudders
• Subject Areas: Design; Marine Transportation; Vehicles and Equipment;

Filing Info

• Accession Number: 00014621
• Record Type: Publication
• Source Agency: Joint Publications Research Service
• Report/Paper Numbers: Russian
• Files: TRIS
• Created Date: Aug 12 1972 12:00AM