This note gives the stress distribution in an infinite wedge subject to a general polynomial law of loading along either edge. The method used is that of Complex Potentials, the results of which may be summarised as follows:—

The stress combinations and and the complex displacement are given in terms of two complex potentials Ω(z) and ω(z) by the relations

1

2

3

body forces being assumed absent and pq denoting the stress intensity across a face perpendicular to p and resolved in the direction q, for a body in a state of generalised plane stress, µ is Lamé's constant and k is related to the modified Poisson's ratio σ, by the equation:

.

The problem of fatigue in aircraft design is a comparatively new one so far as the airframe designer is concerned. There are three main reasons for its prominence. Firstly, the utilisation rate has increased enormously, particularly with transport types; indeed, the hours flown by a civil aeroplane in a single year nowadays far exceed those in the whole life of a bomber up to the period of the 1939-45 War. Secondly, the increased cruising speeds of modern aircraft have aggravated the loading conditions which give rise to fatigue; and thirdly, the development of modern high strength light alloys has enabled higher ultimate stresses to be used, although the fatigue resistance of the material has not kept pace with its ultimate strength.

The modern internal combustion engine, particularly the power unit developed for aircraft propulsion, provides a subject of great metallurgical interest and speculation.

The requirements of the aero engine designer for greater engine power while retaining a low weight/power ratio has inspired research into fuels of improved characteristics, and on the metallurgical side into materials of superior properties to those previously available.

The Journal of the Royal Aeronautical Society, in one form or another, is the oldest aeronautical publication in the World, with a continuous record of publication.

The Aeronautical Society of Great Britain was founded on January 12th, 1866, and the first report of the proceedings of the Society was published in 1867 by the firm of Cassell, Petter and Galpin, of Ludgate Hill, E.C., price Is. 6d.

It was a bold venture to start an aeronautical society in those days, and it is worth while recalling the year 1866. It was the year Prussia became head of the new German confederation which was the beginning of modern Germany, and it was the year that the first treaty of alliance was signed between Italy and Germany.

In those days Dickens, Browning, Tennyson were the giants of their time. Women wore crinolines, shawls and poke bonnets, and men light trousers with frock coats and top hats.

Tests were made at the request of the Royal Aeronautical Society Structures Committee to extend the information on Data Sheet 02.09.02 from a value of the parameter.