On 6th January 1916 Lord Northcliffe, seconding a vote of thanks to Mr. Griffith Brewer for his lecture on the Life and Work of Wilbur Wright, said among other things : “The fact remains, however, that after more than one hundred years of experiment with aeroplanes, these two brothers were the first people in the world who made a machine to fly, and flew it. I make that remark emphatically, because there is one point to which Mr. Griffith Brewer did not call attention, and that is the attempt that has been made to rob the Wright brothers of the credit of their invention. We have not heard much of that in England, but ‘a prophet is not without honour save in his own country,’ and in the United States there have been long and persistent attempts to belittle the work of Wilbur and Orville Wright. I have closely read and followed the history of the hundred years of aeroplane experiments, and I am convinced that the credit of the first flying aeroplane is due to the Wright Brothers, and from the point of practical flying to nobody else. As an Englishman I am in an independent position, and I know that these words of mine will go across the Atlantic, and I believe they will assist in stopping the spread of the insidious suggestion that the Wrights did not invent the aeroplane.”

The title of this paper, “Gas Turbine Accessory Systems,” covers a wide field, and one which is changing all the time. I have known many experimental units devised to perform a certain job, which were discarded almost as soon as they were made for some more up-to-date component and then, after a lapse of months or years, the original units have been dragged out from under the bench or from a museum of relics and pressed into service again with satisfactory results.

The distortion of straight wings is simple and familiar; upward bending causes slight changes in dihedral angle and loads offset either fore or aft of the flexural axis cause twisting, which involves changes in incidence. When wings are heavily swept back, bending causes change of incidence as well as change of dihedral angle, while the changes of incidence due to twisting are no longer equal to the angles through which the wing structure twists.