This paper, presented in Hamburg in Nov. 1977, is part of the 12th Progress Report of the AGSV (the German "Study Group of the Ship Experimental Establishments"). Jastram-Werke GmbH KG, the Author's Company, has been concerned with "active" manoeuvring devices (transverse thrusters, etc.) for many years, and has more recently been co-operating with experimental establishments in the development of "passive" devices such as the Jastram Flossen rudder, a fin- or flap-rudder based on an idea of J. Brix of the HSVA and the subject of this paper. Unlike the Jastram rotor rudder which operates at angles of attack up to 70 deg. or more, the Jastram flapped rudder has an angular range similar to that of a conventional rudder. The hinged flap, at the trailing edge of the rudder and (preferably) hydraulically operated, influences the flow over the "pressure" side of the rudder to increase the rudder effect at the lower ship-speeds. For the higher speeds, the flap moves into the neutral position (this could be done automatically) so that flap and rudder become a single conventional control-surface (this feature obviates the need for heavier scantlings, etc.); with the rudder amidships, the flap alone can be used to steer the ship at service speed. The Author discusses the need for high-performance rudders, describes the features of this flapped rudder, and presents and discusses some results of open-water and other tests on the rudder at the HSVA. The possibility of adding a rotor to a flapped rudder is briefly considered. Order from: BSRA as: No. 48,845.

  • Availability:
  • Corporate Authors:

    Seehafen-Verlag Erik Blumenfeld

    Celsiusweg 15, Postfach 1347
    2000 Hamburg 50,   Germany 
  • Authors:
    • Weiss, F
  • Publication Date: 1978-4


  • German

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00180044
  • Record Type: Publication
  • Source Agency: British Ship Research Association
  • Files: TRIS
  • Created Date: Sep 14 1978 12:00AM