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    Wright explains the effects of weight ratio on flight

    Orville Wright Typed Letter Signed, along with a collection of related documents. Wright's letter, two pages, 7.25" x 10.5", Dayton, Ohio, May 11, 1917. Wright is responding to Charles A. Moran, who made an inquiry about the accuracy of a statement made in an interview published in Harper's Magazine. Wright responds, in part:

    "The statement that the 'weight increases as the cube, whereas the area of the wings increases as its square', is not absolutely correct, but is practically so. In the interview I had called Mr. Hendrick's attention to the fact that the weight of some parts increases only in the same ratio as the area increases. Among these I mentioned the cloth covering which is practically of the same weight per square foot, regardless of the size of the machine. But these parts that increase directly compose such a small part of the total weight that they scarcely need to be considered.

    However, I cannot quite agree with your reasoning as to the relative strength of large and small machines. The structure of a flying machine, upon which its strength depends, is that of a bridge. The greater portion of the total weight of the machine itself, as well as all of the load carried, is usually located approximately centrally between the two wing tips. I explained to Mr. Hendrick that if the weight of the motive power and of the load to be carried could be equally distributed over the entire surface of the machine, there would be no limit to the size a machine could be built and still be strong enough to support its own weight in the air. But unfortunately such a machine would have no strength in landing with any type of landing gear known at the present time. In other words, in landing, some provision would have to be made so that every part of the machine would come in contact with the ground at the same time...Nature has never succeeded in building a large creature which could fly. I believe the Pterodactyl, which was the largest, weighed only in the neighborhood of thirty pounds, and evidently was but a poor flyer. The theory, which I state in the interview, I think, has been fully borne out by the experience of all the flying machine manufacturers."

    Accompanying the letter is the retained carbon of Moran's letter to Wright dated May 5, 1917, and numerous other related documents, such as newspaper articles, notes, letters, etc. The Wright brothers are, of course, famous for being the first to produce an airplane that maintained flight. While there have been controversies about who was exactly the progenitor of the flying machine, they are the most iconic and well recognized. Orville, made the very first flight at Kitty Hawk, North Carolina on December 17, 1903. An excellent letter with extensive technical content.

    Condition: Related documents range from good to near fine. Orville Wright letter is toned throughout with usual mail folds. Three small stains on top half of letter. Two small holes at top left corner where pages were held together. Otherwise fine condition.

    Auction Info

    Auction Dates
    October, 2017
    19th Thursday
    Bids + Registered Phone Bidders: 7
    Lot Tracking Activity: N/A
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