Beschreibung:

WRIGHT, ORVILLE. Typed letter signed in full to Lester D. Gardner of the Institute of Aeronautical Sciences, with two words added and several lines underlined in ink by him, Dayton, Ohio, 2 December 1943. 9 pages, 4to, typed on rectos only, the first on Orville's personal imprinted stationery, minor soiling to a few blank corners. A REMAKABLE NINE-PAGE CONSIDERATION OF THE LANGLEY AIRCRAFT ENGINE OF 1900 One of the longest of all extant letters of the aviation pioneer, documenting Orville's extensive research into early aircraft engines, specifically the Manly-Langley engine. Samuel P. Langley's aircraft, The "Great Aerodrome," had been unsuccessfully tested on the Potomac in December 1903 (only a week before the Wright Flyer's historic flight at Kitty Hawk). The craft was powered by an engine whose design and construction was attributed to Charles M. Manly (1876-1927), Langley's associate at the Smithsonian Institution (see notes to lot ). (Manly also piloted the test aircraft, and nearly drowned in the experiment.) Orville describes in careful detail his investigations of the engine. "I thought you might be interested in what I have leaned...concerning the origin of the Langley motor...through papers foolishly exposed by Manly's friends in an aggressive campaign in his behalf. This activity may be due to the failure...to name the engine laboratory at Cleveland as a memorial to Manly....I had always been friendly to Manly and had always considered the Langley motor as due to him, as is clearly shown in my correspondence." [Wright gives extensive quotations here from his letters on the subject written in 1929 and 1939] Orville is careful to show that his famous quarrel with the Smithsonian and Langley's supporters hinged on the question of whether the rebuilt "Great Aerodrome" flown by Curtiss in 1914 was the same design as that which had failed in 1903. "My personal relations with Manly were always friendly. In the midst of the Smithsonian-Wright controversy, I entertained him at lunch on one of his visits to Dayton. I did not consider Mr. Manly as a party to the fraud perpetrated...in 1914..." Then, as Wright explains, he came upon references to the role of another designer, S.M. Balzer, in the Langley engine design: "This was a revelation to me. I had always believed...that the Langley engine was entirely a creation of Manly's....I was astonished [to learn] that the basic design of the motor was Balzer's, to which some features from European practice and some from Manly had been added...." "Here is an account of the development of the Langley engine as I now understand it....The Balzer engine had five radial cylinders, which rotated about a stationary single-throw crankshaft....Balzer rotated the radial cylinders to eliminate the necessity of water cooling [thereby saving weight] and to make a flywheel entirely unnecessary. [It]...had an ingenious system of lubricating the moving parts by feeding oil through a bored crackshaft. This system, in common use today, was patented by Balzer....[He] was still struggling a year later to get the power up to the required twelve horse. Present-day engine builders know that the development of a new design...requires years....Balzer did not know this when he entered into his contract, nor did Langley or Manly....While Balzer was having trouble getting the motor to perform...Langley and Manly went abroad in 1900 to investigate foreign motors. When Manly returned, he found little progress had been made on the motors...due to Balzer's lack of money to pay wages....Therefore Manly ordered all the parts and the jigs for the motors sent to the Smithsonian shops...." Wright then describes the nature of Manly's modifications to Balzer's engine, and weighs conflicting reports of the horsepower attained in the tests: "Manly states that the static thrust of the Langley propellers...was 450 pounds. When Curtiss and Zahm tested [it] at the Curtiss factory in 1914...only 325 pounds thrust could be