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    <title>Transport Research International Documentation (TRID)</title>
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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    <item>
      <title>A FLEXIBLE PROPELLER SHAFT SYSTEM USING CONSTANT VELOCITY UNIVERSAL JOINTS</title>
      <link>https://trid.trb.org/View/152919</link>
      <description><![CDATA[The Swedish Scatra CVA system combines a separate thrust block with a universally jointed cardan shaft in the main power transmission line and very flexible engine mountings based on Metalastic components.  Order from NSFI as No. 19044.]]></description>
      <pubDate>Tue, 22 Apr 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/152919</guid>
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      <title>CALCULATION OF PROPELLER-EXCITED WHIRLING CRITICAL SPEEDS</title>
      <link>https://trid.trb.org/View/147505</link>
      <description><![CDATA[This paper presents a calculation method, suitable for manual calculation or use with a small, desk-top calculator, for estimating the propeller-excited whirling critical speed of a shafting system.  The method is especially adaptable to use with a small programmable calculator.  Based on a two-support model of the propeller and tailshaft similar to that used in earlier whirling calculations, this method "brackets" the natural frequency by first assuming the forward end of the tailshaft to be simply supported, then repeating the calculation, assuming the forward end to be fixed.  This gives an upper and lower limit on the natural frequency.  The actual natural frequency is estimated by interpolation between these two values.  The proposed calculation method includes propeller gyroscopic and inertia effects, as well as shaft mass effects.  Entrained water may also be taken into account.  Comparisons between the results of the proposed hand calculation and the results of other well-known methods of whirling analysis are presented for a typical vessel shafting system.  Extensions of the proposed calculation to include the effects of the line shafting and the sterntube bearing stiffness are also presented.]]></description>
      <pubDate>Mon, 11 Feb 1980 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/147505</guid>
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      <title>HYDROFOIL CRAFT AND THEIR MARINE ENGINEERING ASPECTS</title>
      <link>https://trid.trb.org/View/2630</link>
      <description><![CDATA[Upon consideration of a general design philosophy for commercial hydrofoil craft, the percentage weight of some structural groups, published by various authors, are discussed and some data are added according to the present state of the art.  Design and analysis problems for the layout of long, inclined propeller shafts, as well as for power transmission by means of bevel gears.  Finally, a brief prospect for assumed future tendencies is given.]]></description>
      <pubDate>Wed, 08 Nov 1978 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2630</guid>
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      <title>PROPULSION MACHINERY CONSIDERATIONS FOR CONTRAROTATING PROPELLER SYSTEMS</title>
      <link>https://trid.trb.org/View/1218</link>
      <description><![CDATA[Contrarotating ( CR ) propellers offer one attractive solution to meeting the needs for higher power, more efficient ship propulsion.  A planetary second-reduction gear system is proposed to provide the CR energy to a pair of propellers from a conventional turbine power source.  The concentric line shafts, bearings, and lubrication system are discussed as vital components to a CR system.  Some favorable full-scale operating experience has been obtained on all components except a high-power second-reduction planetary gear operating in the CR mode.  The use of a CR propeller system should have a significant economic impact on the powering of ships.]]></description>
      <pubDate>Sun, 30 Dec 1973 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/1218</guid>
    </item>
    <item>
      <title>COMPUTER PROGRAM FOR MARINE PROPELLER SHAFTS</title>
      <link>https://trid.trb.org/View/6407</link>
      <description><![CDATA[The program carries out detailed analysis of marine propeller shafts.  The basic data required are the shaft dimensions, up to 100 lengths of different circular cross-section-hollow or solid-being allowed, the bearing positions, 20 being considered, and any point loads to which the shaft is subjected.  The propeller weight and gear wheel weight are examples of such loads.  The specific weight and modulus of elasticity of the shaft material are also required.  For the convenience of the engineer the program is written in a dimensionless form and will accept any convenient set of units, imperial or metric.]]></description>
      <pubDate>Sat, 20 Oct 1973 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/6407</guid>
    </item>
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      <title>ALGORITHM FOR STATICAL CALCULATION OF SHIPS SHAFTLINES--2</title>
      <link>https://trid.trb.org/View/2627</link>
      <description><![CDATA[The formulas given in this article take into account the effect of the axial force set up by propeller thrust. Although for large ships, this effect is slight.  The reason for using this algorithm is that it transforms the original matrix by solving equations with free terms as a unit matrix.  This makes it possible to determine the support points for a propeller shaft approximately.]]></description>
      <pubDate>Wed, 08 Nov 1972 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2627</guid>
    </item>
    <item>
      <title>NOTE ON WAVE INFLUENCE ON PROPULSION SYSTEMS</title>
      <link>https://trid.trb.org/View/2817</link>
      <description><![CDATA[Development of new theories and computer programs in the course of recent years has made it possible to predict the short term and long term motions of ships in irregular seas.  It has also been found that a predictable relationship exists between the wave system, the motions of the ship and the dynamic loading of the propeller blade and shaft.  Until now these influences have not been included in the design procedures for propellers and shafts except as a safety factor through low nominal stresses.  It is the writer's opinion that suitable, simplified methods now exist for prediction of the wave effects on propellers in the design stage.]]></description>
      <pubDate>Fri, 11 Feb 1972 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2817</guid>
    </item>
    <item>
      <title>NEW SYSTEM SPEEDS REMOVAL OF TAILSHAFTS</title>
      <link>https://trid.trb.org/View/2605</link>
      <description><![CDATA[Direct labor requirements for removal and replacement of shafts, propellers and rudders on U.S. Navy ships at the Long Beach, Calif., Naval Shipyard have been reduced some 80 percent by the use of a new rigging technique.  The Elpar Mobile Precision System, operated in the drydock, consists of two high-platform trucks, and a pallet which is symmetrically constructed and allows truck platform entry from any of four sides.  The pallet's 120 in. square horizontal surface is divided into identical halves.  Each section has a movable plane that occupies 1/8 of the total horizontal surface.  Each section and plane may be controlled individually or in unison.  Control is left-right and/or forward-reverse.  Two telescoping uprights attached to each section lift the pallet.  A hydraulic cylinder inside the upright provides vertical movements to the mounting plate, on which interchangeable component-carrying arms are attached.  Details are given for the trucks, and the procedures used in removing propellers, shafts and rudders are described.]]></description>
      <pubDate>Fri, 29 Oct 1971 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2605</guid>
    </item>
    <item>
      <title>GUIDE FOR THE DESIGN OF LINE SHAFT COUPLINGS</title>
      <link>https://trid.trb.org/View/890</link>
      <description><![CDATA[The guide contains a selection and design table of recommended line shaft coupling and bolt details for various diameter ship propulsion shafting.  It is the result of an investigation of line shaft flange bolting practices for turbine, diesel, and motor drives, conducted by SNAME Panel M-16 ( Modernization of Propulsion Shaft System ) of the T&R Ships Machinery Committee.  The latest requirements of five major International Classification Societies were considered in preparing this guide.]]></description>
      <pubDate>Tue, 23 Mar 1971 00:00:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/890</guid>
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