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Aviation History
1956
1956 - 0642.PDF
642 FLIGHT THE DE HAVILLAND D.H.9A ... made its first bench run on July 23, 1917, and was first flown inan L.W.F. Model F biplane on August 20. A twelve-cylinder version of the Liberty engine had been putin hand at the same time as the eight-cylinder prototype, and successfully completed a 50-hour bench test on August 25, 1917.The Liberty 12 was originally rated at 314 h.p., but its output was raised to 395 h.p. by October 1917, in which month it wasflown in a D.H.4. In view of operational demands for the most powerful engines possible, development of the eight-cylinderLiberty was virtually abandoned in December 1917 and work was concentrated upon the twelve-cylinder version. The Liberty 12 was a water-cooled vee-type engine, with anangle of only 45 deg between the cylinder banks. The cylinders were steel shells which were surrounded by pressed steel waterjackets; bore was 5in, stroke 7in. In its ignition system the Liberty broke away from contem-porary practice, for it employed a high-tension coil in place of the magnetos which then had universal acceptance. It was said thatthis startling innovation had been made in the interests of weight- saving. There may, however, have been some significance in the originof the engine's ignition system. It was manufactured by the Dayton Engineering Laboratories Corporation (Delco), a concernwhich had been formed in 1911 by E. A. Deeds and Charles F. Kettering. Deeds and Kettering sold out at a handsome profitto the United Motors Corporation in 1916, while yet retaining lucrative positions with Delco. In\April 1915, Deeds, Kettering, ':ii__ FEET DE HAVILLAND D.H.9.A. H. E. Talbot, Senr., and H. E. Talbot, Jnr., had establishedthe Dayton Metal Products Company, which soon won profit- able British contracts for the manufacture of fuses. By early1917 the new company had bought a substantial interest in the Dayton-Wright Aeroplane Company, which had been organizedin 1916 with a view to profiting from the large war contracts likely to be placed by the combatant nations. The other major interestin the Dayton-Wright concern was held by a Detroit group which was headed by Howard E. Coffin, vice-president of theHudson Motor Car Co.; Henry Leland of the Cadillac concern; and J. G. Vincent of Packard, co-designer of the Liberty engine.Parenthetically it may be noted that the financial background to the American aircraft industry of 1917-18 makes astoundingreading, and in it the story of the Liberty engine's ignition system was but a part. But for that the reader is referred elsewhere. *It has been recorded by J. G. Vincent that "Although the [U.S.] government asked for five 12-cylinder enginesand five 8-cylinder engines on a test-run, the project to supply the Allies with an engine that could be mass-produced quite possiblywould have died had not England promptly cabled an order for 1,000 of them as soon as the endurance test on the first 12-cylinder modelwas completed. Actually, the order to build production Liberty engines for the Army and Navy was not definitely given until September 1917.The first production-built motor was sent to Washington on Thanks- giving Day that year." Britain's interest in the Liberty was understandable, for itappeared at a time when supplies of Rolls-Royce engines were falling far short of demand, and there was an urgent need for apower unit of comparable output. The precise date of the first British order for the Liberty does not seem to have been recorded,but Vincent's note indicates that the order may have been placed at the end of August 1917 and cannothave been later than early September 1917. It is known, however, that by January 1918 the totalnumber of Liberty engines ordered by Britain had reached 3,000. Deliveries were to be made at therate of 500 per month, commencing in January 1918. Unfortunately, the ambitious production pro-gramme for the Liberty was never realized, and schedules were repeatedly revised downwards. Itwas estimated on November 1, 1917, that 55 engines would be delivered that month and 280 in Decem-ber; by May 1918, output would be at the rate of 4,800 per month, and total production by May 31was expected to be 9,420. In fact only 1,100 Liberty engines had been completed by May 25. Production of the Liberty was undertaken by anumber of American automobile manufacturers, and an informal production committee, consistingof engineers and production managers of the Packard, Ford, Cadillac, Lincoln, Marmon andTrego companies, was set up. It comes as no surprise to learn that the Ford company evolved aspecial technique for the production of cylinder forgings; by May 1918 forgings were produced atthe rate of 1,700 per day. Lack of the necessary tools, jigs and gauges delayed production in theearly stages, and the allegedly "perfected" engine needed quite as many modifications as its con-temporaries. There is a hint of anguish in the report made by one contractor that 1,022 designchanges were made between September 1917 and February 1918. The combination of these difficulties was aformidable one, yet the production of 1,100 engines of a new type only twelve months after design workwas initiated should be recognized for the fine achievement that it undoubtedly was. Once pro-duction gained momentum the output of Liberty engines increased rapidly, and by the time of theArmistice a total of 13,396 had been delivered. The output for the month of October 1918 was no lessthan 4,200 engines. On the strength of the original optimistic fore-casts of production, huge orders for the Liberty were placed. The engines were not only wantedfor aircraft: the American Army Ordnance Bureau ordered them for installation in tanks. With the progressive scaling-down of output,the fulfilment of the British orders for the Liberty was never achieved. Deliveries to Britain did notbegin until March 1918, in which month 10 were delivered. Twenty more came in April, 175 in May,225 in June, and 620 in July. Deliveries then stopped, and on September 25, 1918, Mr. Winston *See "Airways," by Henry Ladd Smith (Knopf, 1942), Chapter 3.
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