Wow, I had this in an E~Mail attachment sent by...
E M D Here's one My Dad sent me Via E~Mail coincedently right arround memorial day. The Email heading read " You think your Cummins can work in a War~Floater?"
The Deltic Engine
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The 2,500hp, marine version of the Deltic engine had an established ancestry. The design was most unusual, an 18-cylinder, opposed piston two-stroke engine, with the cylinders arranged in three banks of six, having common crankshafts at each corner of the triangularly shaped engine. The bank of six pistons demanded the triangular shape, hence the outline of an inverted Delta.
The Napier Deltic Engine from the Deltic Locomotive 50 018 Ballymoss.
Napier’s aero engine. The opposed-piston two-stroke concept used in it dated from 1929, developed by the firm of D. Napier & Son which had acquired the know-how from the German aviation company Junkers Motorenbau in 1930. The Napiers were an experienced English engineering concern with a reputation for high standards of workmanship and reliability originating as a family enterprise in the late eighteenth century. It was with the stimulus of aircraft demands that Junkers had needed to create a compression-ignition engine of very high power/weight ratio. The resulting Jumo 205 was a 6-cylinder opposed-piston two-stroke vertical design, i. e. having two pistons at opposite ends of each cylinder firing once per crankshaft revolution. Low fuel consumption suited this engine to fitting in long-range reconnaissance aircraft. Napiers, as suppliers of aero engines, were looking for innovations to build on their established success. They acquired the requisite blueprints and started building prototype engines - only for these to be abandoned when the onset of war in Europe diverted attention to mass production of existing designs.
English Electric developes it further. Ironically it was another military requirement, this time from the Navy, which brought about a resurgence of interest in the project. In 1947 a requirement was identified for a fast torpedo boat engine, and the work was offered to English Electric. As its name implies, English Electric, formed in 1918 by the amalgamation of several smaller concerns, was originally involved with electrical and associated equipment alone; but in the following thirty years it had gone on amalgamating, thereby acquiring substantial diesel engine interests as well. Mainly this side of its operations had been responsible for the heavyweight and massively successful range of engines which began by powering railway shunting locomotives, but during the war it had also assimilated Napiers, to whom this latest requirement was more suited. The result was the Jumo 205 arrangement multiplied into the 3-bank triangle ‘Deltic’ engine range. This gave it compactness and great strength, while the use of new alloys also made it exceptionally light. By 1952 the first 18-cylinder engine had been installed in a patrol boat running at an output of 2,500hp.
Nelson’s vision. Lord Nelson, by then a director of English Electric, saw no reason why the engine should be restricted to marine applications and looked to the wind of change blowing through the railways to provide an alternative market. High power with low weight had previously been a contradictory concept on railways, where conventional steam locomotive design which lost part of the total weight from adhesion usually needed all it could get of the remainder. In a diesel locomotive carried on bogies; the whole of the weight was available for adhesive purposes, ehhancing its potential for hauling heavy loads at high speed. Use of engines as light as the Deltic type would also get around the axleloading problem, whereby track which was in a poor state still recovering from the ravages of the war had been a severely limiting factor. Axleloadings at that time had forced most of the seven main-line diesel locomotives already in existence to ponderous dimensions and wheel arrangements up to 1Co-Col to appease the civil engineers, for fairly modest power output, and the Deltic power/weight ratio offered the chance to break away dramatically. The ‘Delta’ shape saved space, while the opposed pistons which shared the cylinder saved weight. The engine operated on a two-stroke cycle, hence there are no inlet or exhaust valves or camshafts. However, this arrangement is very polluting and would be avoided today for environmental reasons.
The internal gearing mechanism of a Deltic Engine
This complex assembly of gear phasing mechanism is required to syncronise the output of the three crankshafts into a single output (the middle-sized gear in the centre of the triangle) so that none of the pistons work against each other in use. Systems like this can introduce friction into the system, but this is more than compensated for by the weight saving in using such an arrangement, brought about by the opposed pistons and common crankshafts.
The deployment in the prototype locomotive. Under Nelson’s responsibility a prototype locomotive was built, incorporating two of the 18-cylinder Deltic engines. The gamble was opposed internally by the English Electric Traction Division, which had more than a little vested interest in the conventional alternatives and did not want their highly respected reputation tarnished by an expensive mistake; also precedent was against it: other unconventional locomotive designs such as the Turbomotive, the water-tube 10000, Bulleid’s “Leader” had all failed to multiply. The eventual expense was to be some £250,000, but the locomotive went ahead. To adjust from marine conditions to the demanding, unstable, vibration-ridden railway environment, a third of the power was sacrificed by derating the engines to 1,650hp each. Even so it was still to be the most powerful single-unit diesel locomotive in the world, and the derating enabled service life between overhauls to be extended from the marine 1,000 hours to the 6,000 hours which represented a railway year’s work. This was still a relatively short life by the 10,000+ hours standards of conventional four-stroke engines, but a further balancing factor was that the small lightweight engine units lent themselves to rapid unit replacement. The comparatively small amount of routine maintenance otherwise needed by the almost totally sealed engine, in the absence of normal valves, tappets and cylinder-head joints, was understandably appreciated by hard-pressed depot staff. (Note from Ralph Barrett: The prototype DELTIC locmotive had its power units overhauled at 4,000 hours periodicy. 6,000 hours was only achieved much later in BR days for the production machines. )
Recognition of Engine Engineers. a few days back, I received this e-mail from John Favill, who had something to say about his days back Henry Meadows. Being too painfully aware of the days when the credit went to the company leader and not the actual man with the idea, I have decided to publish his e-mail in full. I have no idea whether this story is accurate, but given famous examples in the past such as the design of the two-stage piston, often credited to Stephenson, was actually a design by a company mechanic which he sold to his master for £20. (See also the British Rail class 86 article. ) Such loyalty to the company in itself is commendable, for I wish the workforce today was as loyal as they were in the mid 19th century.
Date: Thu, 17 Jun 1999 11:43:22 -0500
From: John Favill <jfavill@execpc.com>
Subject: Deltic diesel engines.
Many years ago, more than I care to remember, I was apprenticed towards the end of WWII, at a design and manufacturing company of internal combustion engines and transmissions in Wolverhampton. The name of the company was Henry Meadows Ltd.
Towards the end of my apprenticeship I was employed in the design office and one of the very senior, in years and in status, design engineers was a Mr. Pennwarden. These were still the days when the senior engineers were always addressed as “Mr”, never christian names, so I have to trust my long term memory in thinking his christian name was Herbert. . Mr. Pennwarden had won, so the story goes, a substantial money prize, in the 1930’s, in a design competition for a proposal for a compact high power diesel engine for use by the British Admiralty. The engine designed by Mr. Pennwarden was the Deltic engine. This is a story that I would delight in, if it was true. As a frustrated engine designer in England it was not until I emigrated to the US did I find, perhaps not too much fame but certainly a little fortune.
It is my belief that engine designers as a breed are never recognized for their contributions and I call it the ‘Charles Taylor Syndrome’. I would like to see Mr. Pennwarden recognised for his contribution to the Deltic story.
Incidentally Charles Taylor was the man who helped design the engine used by the Wright Brothers in December of 1903. He made all the parts, assembled and tested the engine and even glued on the propeller and who knows the name of Charles Taylor?
Thanks are due to Platform 13 and D. Bradford for much of these information. The book on Deltics by Bradford is published by Barton Books Ltd. Also available is a ‘Deltic’ booklet, published by the National Railway Museum, York in December 1981, ISBN 0-7003-0042-2.
Attention: TDR Forum Junkies 
