bluuebunny/crossref_metadata_2025 huggingface dataset:
The Irish court of claims of 1663
Authors: Arnold L. J.
Published: August 2016

The modification of the Cromwellian land settlement in Ireland which followed the restoration of the Stuart monarchy in 1660 was regulated by two acts of parliament, one familiarly known as the act of settlement of 1662, the other as the act of explanation of 1665. They became the principal legal instruments upon which land ownership in the country was to rest for two centuries.

The act of settlement was the statutory version, with the major addition of a preamble, of the so-called ‘Gracious declaration’ of 30 November 1660, a royal proclamation which enunciated the broad principles upon which the settlement was to be based. In its statutory form these principles were: the vesting in the king, as trustee for the purposes of the act, of all land confiscated since 23 October 1641 as a consequence of the rebellion, with the general exception of the land held on that date by the church and Trinity College, Dublin; the general confirmation to the adventurers and Cromwellian soldiers of the land they held on 7 May 1659; and the restoration of various classes of dispossessed proprietors, chiefly those catholics who could prove, before the commissioners appointed to execute the terms of the act, that they were innocent of having participated in the rebellion. Those found innocent were to be restored to their estates immediately without having to wait until the Cromwellian planters had first been ‘reprised’ (i.e. compensated) with land of equal value.
VI. Sir Niall Garbh O'Donnell and the Rebellion of Sir Cahir O'Doherty
Authors: Ó Domhnaill Seán
Published: August 2016

Writers of Irish history who treat in any detail of O'Doherty's rebellion, take, almost without exception, the view that the charge of complicity therein preferred by the authorities against Sir Niall Garbh O'Donnell was well-founded. D'Alton states that Niall Garbh was in collusion with O'Doherty; Bagwell that he was a fellow-conspirator. Lord Ernest Hamilton arrives at the conclusion that no doubts can remain of his guilt. Meehan asserts that Niall Garbh advised O'Doherty to march on Derry and massacre the English settlers in the market-square; and Dunlop writes that the attorney general had little difficulty in accumulating proof of his correspondence with O'Doherty. Let the matter be examined.
Triticale out-performs wheat on range of UK soils with a similar nitrogen requirement
Authors: ROQUES S. E. , KINDRED D. R. , CLARKE S.
Published: August 2016

Triticale has a reputation for performing well on poor soils, under drought and with reduced inputs, but there has been little investigation of its performance on the better yielding soils dominated by wheat production. The present paper reports 16 field experiments comparing wheat and triticale yield responses to nitrogen (N) fertilizer on high-yielding soils in the UK in harvest years 2009–2014. Each experiment included at least two wheat and at least two triticale varieties, grown at five or six N fertilizer rates from 0 to at least 260 kg N/ha. Linear plus exponential curves were fitted to describe the yield response to N and to calculate economically optimal N rates. Normal type curves with depletion were used to describe protein responses to N. Whole crop samples from selected treatments were taken prior to harvest to measure crop biomass, harvest index, crop N content and yield components. At commercial N rates, mean triticale yield was higher than the mean wheat yield at 13 out of 16 sites; the mean yield advantage of triticale was 0·53 t/ha in the first cereal position and 1·26 t/ha in the second cereal position. Optimal N requirement varied with variety at ten of the 16 sites, but there was no consistent difference between the optimal N rates of wheat and triticale. Triticale grain had lower protein content and lower specific weight than wheat grain. Triticale typically showed higher biomass and straw yields, lower harvest index and higher total N uptake than wheat. Consequently, triticale had higher N uptake efficiency and higher N use efficiency. Based on this study, current N fertilizer recommendations for triticale in the UK are too low, as are national statistics and expectations of triticale yields. The implications of these findings for arable cropping and cereals markets in the UK and Northern Europe are discussed, and the changes which would need to occur to allow triticale to fulfil a role in achieving sustainable intensification are explored.
Effectiveness of 3 per cent boric acid in 70 per cent alcohol versus 1 per cent clotrimazole solution in otomycosis patients: a randomised, controlled trial
Authors: Romsaithong S , Tomanakan K , Tangsawad W , Thanaviratananich S
Published: August 2016

Objectives:

To compare the clinical effectiveness and adverse events for 3 per cent boric acid in 70 per cent alcohol versus 1 per cent clotrimazole solution in the treatment of otomycosis.

Methods:

A total of 120 otomycosis patients were randomly assigned to receive either 1 per cent clotrimazole solution (intervention group) or 3 per cent boric acid in 70 per cent alcohol (control group) at the Khon Kaen Hospital ENT out-patient department. Treatment effectiveness was determined based on the otomicroscopic absence of fungus one week after therapy, following a single application of treatment.

Results:

After 1 week of treatment, there were data for 109 participants, 54 in the clotrimazole group and 55 in the boric acid group. The absolute difference in cure rates between 1 per cent clotrimazole solution and 3 per cent boric acid in 70 per cent alcohol was 17.9 per cent (95 per cent confidence interval, 2.3 to 33.5; p = 0.028) and the number needed to treat was 6 (95 per cent confidence interval, 3.0 to 43.4). Adverse events for the two agents were comparable.

Conclusion:

One per cent clotrimazole solution is more effective than 3 per cent boric acid in 70 per cent alcohol for otomycosis treatment.
The Centre of Shear for Sections Bounded by Two Circular Arcs
Authors: Whitehead L. G. , McQuillin L. A.
Published: August 2016

In two recent notes Jacobs and Duncan considered the St. Venant torsion and flexure problems for beams of aerofoil cross section and have given methods for determining the centre of shear once the torsion function for the section has been found. The purpose of the present note is to give results for the location of the centre of shear for a limited range of cross sections bounded by two circular arcs for which the torsion function has long been known. The calculations shed some light on the relative influence of camber and thickness on the location of the centre of shear and are compared with the well known results for thin circular arc sections illustrated in the Structural Data Sheet 00.06.04.
Some Blade Designs for an Axial Flow Compressor Stage
Authors: Taylor R. G.
Published: August 2016

Two design conditions for an axial flow compressor stage are proposed and examined. These are, the constant reaction condition (incorporating I “ radial equilibrium ”), and the condition that the Mach number at inlet to the rotor shall be invariant with radius. In addition, the combination of these two properties in one stage is considered. It is found, with further assumptions regarding the nature of the flow, that a forced vortex type of flow will satisfy both design specifications. The forced vortex solutions for the various cases are presented, and for constant Mach number at inlet to the rotor, more general solutions are given.
Aerodynamic Noise
Authors: Lilley G. M.
Published: August 2016

The heading aerodynamic noise includes all cases where sound is generated by fluid flows. It includes aeolian harps, edge tones and related phenomena as well as vortex, boundary layer, wake and jet noise. In the strict sense it does not include propeller noise and the direct noise generated by; bodies in motion. However, in view of their importance as sources of aircraft noise some of their more important aspects will be discussed briefly and compared with the similar properties of pure aerodynamic noise.

In general it is audible aerodynamic noise which is of major interest at present, but it would be unwise to neglect entirely the ultrasonic aspects. These have received little attention as yet.
Internal or Residual Stresses in Wrought
Aluminium Alloys and their Structural
Significance
Authors: Forrest G.
Published: August 2016

In the design and production of structures it is commonly assumed that the raw material supplied in the form of bar, sheet, forgings and castings is homogeneous, isotropic and stress-free. Some failures in service and more in the laboratory have drawn attention to the possible dangers arising from inhomogeneity, directional properties and residual stresses. It is the purpose of the present paper to review the situation with regard to the last, which the production engineer, who has to cope with distortion on machining, at least cannot ignore.
Modern Experimental Work on Aeroplane Structures
Authors: Pugsley A. G.
Published: August 2016

A meeting of the Society was held in the lecture hall of the Institution of Mechanical Engineers at Storey's Gate, St. James's Park, Westminster, London, S.W.1, on Thursday, April 5th, 1945, at which Dr. A. G. Pugsley, F.R.Ae.S., presented a paper entitled “Modern Experimental Work on Aeroplane Structures.”
Wing Testing: A Method of Testing the Wing Structure of Large Aircraft Adopted by Vickers Armstrong
Authors: Gardner H. H.
Published: August 2016

During the lecture on structural testing given by Dr. Pugsley to the Royal Aeronautical Society, reference was made to the work done at Weybridge on the strength testing of aircraft wings, and during the discussion the lecturer suggested that details of this work should be submitted to the Society for publication. This paper attempts to give a brief outline of some of the more interesting developments which have taken place during the war period, together with a few notes on the arguments which led to the adoption of the final form of test gear.
Some Aspects of the Mechanical Properties, uses and Manipulation of Aluminium Alloys
Authors: Smith F. R. C.
Published: August 2016

It may be said that the title of this paper covers too wide a scope to be dealt with satisfactorily in the time available and that as a consequence the treatment of each section will be of a sketchy nature.

This is undoubtedly a justifiable criticism, particularly from the point of view of a specialist, but the aim has been to present what it is hoped will be helpful information of a practical nature to builders of aircraft rather than aero engines. There is no intention to enter deeply into the technical aspects of the applications of aluminium and its alloys to aircraft, but rather to review some of the many problems and enquiries which have been encountered during several years' contact with the aircraft industry.
Notes on Aero Engine Research
Authors: Rayner P. H.
Published: August 2016

When the writer undertook the preparation of this paper, he rapidly discovered that it was not easy to find any branch of the subject which had not already been dealt with exhaustively by far abler pens than his. One or two matters have, however, been chosen about which information is somewhat meagre or scattered, and which may not, perhaps, be familiar to the aircraft engineer.

First a review will be made of the various types of electronic engine indicator which have been developed up to the present time; this instrument is coming into prominence now, and although it has by no means reached a state of perfection, it is a valuable asset in the hands of the research engineer for the study of fuel problems and other minor points.
The Influence of Aircraft Gross Weight upon the Size and Weight of Hulls and Fuselages
Authors: Rosenthal L. W.
Published: August 2016

In this paper an attempt has been made to trace the influence of gross weight, as the accepted measure of size, upon the dimensions of hulls and fuselages and from this, to evaluate the probable trend of the weights of these components with increasing gross weight.

During the past few years the size and gross weight of aircraft have rapidly increased and there appears at the moment little, if any, structural limit upon the size and gross weights attainable, since it can be shown that the percentage weights of hulls and fuselages tend to decrease as size increases.
The General Theory of Cylindrical and Conical Tubes under Torsion and Bending Loads
Authors: Hadji-Argyris J. , Dunne P. C.
Published: August 2016

In 3.2.1 it was indicated that ξi, ηi may be found from the appropriate co-factors of the secular equation and appear directly as functions of the geometric and elastic properties of the root cross-section. The method will be applied in 5.6.2 for the four-boom tube, in 5.7.3 for the n-boom tube, and in 5.8 for the trapezoidal tube with direct stress carrying top and bottom panels. This procedure is advantageous when it is desired to study the effect on ξ, η of varying particular parameters of the cross-section.

However, when in any case the h-functions have to be obtained, it is often more expedient to determine ξ, η by one of the following procedures.
Relative Eddy and its Effects on the Performance of a Radial Bladed Centrifugal Impeller
Authors: Reddy K. R.
Published: August 2016

Mathematical and experimental methods for estimating the relative eddy velocity in a radial bladed impeller channel have been determined to replace the empirical velocity so far used in designing and predetermining the performance. The effect of this relative eddy velocity on rotor performance has been experimentally determined on a specially designed compressor and compared with mathematical calculation.
Determination of the Buckling Load of Struts with Successive Approximations
Authors: Ratzersdorfer J.
Published: August 2016

In cases of tapered struts with hinged or built-in ends where the exact determination of the buckling load is complicated it may be useful to apply a method of successive approximations.

Let us first consider a bar of the length l with hinged ends under the action
of the compressive force P. The differential equation of the bending line becomes

where v is the deflection at the section u, v with the moment of inertia I (u) and E is Young's modulus. At the ends of the bar the deflection v is equal to zero (Fig. I).
Notes on the Flow of Scheduled Air Traffic
Authors: Adler R. B. , Fricker S. J.
Published: August 2016

This report presents an abbreviated summary of theoretical studies made by a group at the Research Laboratory of Electronics, Massachusetts Institute of Technology, under contract with the Air Navigation Development Board of the Department of Commerce. The details of the analysis and the results have been treated more comprehensively in two technical reports of the Research Laboratory of Electronics.
Cascade Blade Flutter and Wake Excitation
Authors: Parry J. F. W. , Pearson H.
Published: August 2016

A new method of presenting the aerodynamic data for a compressor or turbine blade cascade is shown, with particular reference to flutter excitation or damping. The application of these results to wake excitation is demonstrated.

The basic equations for flutter excitation or damping are derived in the paper “The Aerodynamics of Compressor Blade Vibration” presented by H. Pearson at the 1953 Anglo-American Conference (London). No new equations are derived but the method of plotting the relevant data leads to a simpler appreciation of the criteria.
A Null Method for the Measurement of Load in Axial Fatigue Testing Machines
Authors: Billing B. F.
Published: August 2016

The usual method of load measurement with strain gauge load cells in a bridge circuit involves the measurement of the out of balance voltage either by the height of a trace displayed on a cathode ray oscilloscope, or the width of a band produced by a tuned galvanometer. Both involve careful regulation of the input voltage or calibration during use. The method described provides for a null balance of the bridge at any instant in the cycle of a uniformly repeated cyclic load up to 10,000 cycles per minute. An accuracy of ±½ per cent, of the capacity of the load cell is obtainable.
Further Development of a Boundary Layer Profile for a given Pressure Distribution
Authors: Görtler H.
Published: August 2016

The following paper forms a continuation of a recent work by Prandtl (I) “On the Calculation of Boundary Layers.” It deals with the problem of developing in detail the method, proposed in that paper, for continuing a given velocity profile in a laminar boundary layer when the pressure distribution is given; the method is tried out in practice by numerical evaluation of an example.
Influence of Recent Civil Airworthiness Requirements on Aircraft Design
Authors: Tye W.
Published: August 2016

In preparing this lecture I found it necessary, when considering recent changes in aircraft design, constantly to ask myself the question “Is this particular change due to airworthiness requirements or does it arise from reasons other than airworthiness?” In fact, one must consider whether requirements have any influence at all on the development of trends in design. Should design be likened to a runaway horse with requirements following some way behind, or are requirements a strict rein by which the pace and direction of design is controlled?

My own answer to these questions is that the pace at which development takes place is not influenced at all by airworthiness requirements, but that requirements help to prevent design from running off the path of safety. To carry the analogy a little farther, the faster the development is, the more difficult it is to keep it running on the path of safety.
Aircraft Accidents can Chances of Survival be Increased?
Authors: Hardingham R. E.
Published: August 2016

I feel that it is now more necessary than ever before to present some unbiased views on the subject of aircraft accidents in general and of crash survival in particular. Discussion of the subject must surely be useful, although the outcome may not necessarily be wholly welcome to all sections of the Aircraft Industry.
Variable Distributed Loads in the Theorem of Three Moments
Authors: Turton F. J.
Published: August 2016

The Theorem of Three Moments in a simple form, referring to bending moments at any three consecutive supports A, B, C, of a continuous beam uniform in each bay, AB = a, BG = c, takes the form

w and being constant load intensities over AB and CB respectively.

On p. 159, Vol. 42 (1938), of this journal, Capt. J. Morris discussed a modification in this case (and in the more general case when the beam is in thrust) when the load intensity varies according to a parabolic law.
Primary Instability of a Panel of Integral Construction with Unflanged Stiffeners
Authors: Yusuff Syed
Published: August 2016

A theory of primary failure of compression panels of integral construction with unflanged stiffeners is presented, involving rotation, or translation, or rotation and translation of the stiffeners with the corresponding distortion of the sheet without deformation of the cross sections in their own planes. The investigation shows that the failure may occur generally either by pure torsion of the stiffener with the associated lateral distortion of the sheet or by pure flexure in accordance with whichever mode yields a smaller stress. The theory is compared with the test results covering a fairly wide range of the dimensions involved. The theory is in complete agreement with the experiments. The accuracy of the result thus obtained indicates that the fillets at the junction of the skin and the stiffener are not important and their effects may safely be disregarded.
Effects of Fuel Type on the Performance of Aero Gas Turbine Combustion Chambers, and the Influence of Design Features
Authors: Sharp J. G.
Published: August 2016

The performance of aero gas turbine combustion chambers is discussed under the following headings : Combustion efficiency, combustion stability, ease of ignition, deposits, exhaust temperature variation, and smooth combustion. It is shown that, as assessed by these criteria, combustion chamber performance can be significantly affected by fuel characteristics; also that the effects of fuel type can be greatly modified by equipment design changes. The conclusion is that most of the problems- aggravated by fuel characteristics are better solved by modifications to equipment, if fuel availability and cost are not to be adversely affected.
Gusts and their Measurement
Authors: Taylor J.
Published: August 2016

From the earliest days of flying, gusts have been a problem for aircraft. In the very early flights aircraft were flown only when it was nearly dead calm and few gusts were met. Later on and, in fact, almost up to the Second World War, flying was greatly restricted by the ground and air conditions at the aerodrome. This meant that there had to be fairly good visibility and that the grass aerodrome must not be unduly softened by water. Since the war, aircraft have been flown with much greater regularity.
Definition of Specific Impulse
Authors: Price E. W.
Published: August 2016

The collected comments of Messrs. Greenwood (December 1953 and October 1954 JOURNAL), Thorne (February and October 1954 JOURNAL), and Asquith and Whitaker (May and October 1954 JOURNAL) on the definition of specific impulse in the field of rocket propulsion argue certain traditional points of view, each of which has enough merit to gain proponents but apparently not enough merit to gain universal acceptance.
Looking Forward
Authors: Roxbee Cox H.
Published: August 2016

The list of the Wilbur Wright lecturers is a long and distinguished one, and I feel it a great honour to have been asked to join this eminent company. I was invited just before Christmas, 1939, to address you to-night on the future of British civil aviation. I felt then that though only with great difficulty would it be possible to produce a lecture under war conditions, the invitation must be accepted, firstly because no greater compliment can be paid an aeronautical engineer, and secondly, to support the Council's policy of continuing the Wilbur Wright lectures, which were not interrupted by the last war, through this one.
The Use of Dummies in the Camouflage of Operational Aerodromes
Authors: Yassin E. Z.
Published: August 2016

Dummies are particularly suitable for use in camouflaging operational aerodromes; they not only serve to mask the aircraft and equipment stationed thereon, but also make it possible to give the flying field the aspect of being unusable for flying purposes.

In recent wartime practice, dummies have been extensively used for aerodrome camouflage, and have proved particularly effective, since an enemy flying over the area in which an operational aerodrome is situated, will usually omit to take notice of dummies imitating local features of the landscape, and concealing the purpose for which the terrain is actually being used.
High Wing Loading and Some of Its Problems from the Pilot’s Point of View
Authors: Fraser H. P.
Published: August 2016

It is indeed a very great honour for so new a member to be accorded the privilege of reading a paper before the Royal Aeronautical Society, and I would like to express my sincere thanks to the President and the Council of the Society for the invitation extended to me.

We have heard from designers and experts in all branches of aeronautics what problems confront them and how they propose to solve them. I am going to discuss, from the point of view of a pilot, some of the problems that seem to me to arise from high performance and increased wing loadings, and to indicate what appear to me to be possible solutions. I propose to consider these problems under five headings :—

(1)

Take-off.

(2)

Irreversible Aileron Control.

(3)

The Approach.

(4)

Flattening Out

(5)

Touching Down.
The Behaviour of Structures Under Repeated Loads
Authors: Pugsley A. G.
Published: August 2016

In recent years some types of aircraft have shown signs of structural trouble due to repeated loading and exploratory thought has therefore been given to the general problems arising. There are two main aspects to be considered: the nature and magnitude of the loads repeatedly occurring in flight and the behaviour and strength of aircraft structures under such loads. In this country a good deal of attention has already been given to the first side of the question, mainly by V-g recorder work, but also by some strain gauge investigations, but the other side of the matter—the resistance of aircraft structures to repeated loading— has so far received less attention. Direct experiments have not in this country gone much beyond exploratory work on a series of Typhoon tailplanes, described by Oaks and Townshend.
The Use of Rheo-Electrical Analogies in Certain Aerodynamical Problems
Authors: Malavard L.
Published: August 2016

A meeting of the Royal Aeronautical Society was held in the Library of the Society at 4 Hamilton Place, London, W.l, on Tuesday 25th September 1945, at which M. L. Malavard, of the Laboratoire des Analogies Electriques, Paris, lectured on “The Use of Rheo-electrical Analogies for the solution of Aerodynamical Problems.” In the chair, Mr. E. F. Relf, C.B.E, F.R.S., F.R.Ae.S. (at that time Superintendent of the Aeronautics Division, National Physical Laboratory).
Some Economic Aspects of Transport Aeroplane Performance
Authors: Mentzer W. C. , Nourse Hal E.
Published: August 2016

Total air transport operating costs are divided into three general classifications : (1) Significant operating costs which are defined as those resulting from the flight of an aeroplane or those affected by variation of aeroplane size, power, initial cost, and aerodynamic efficiency. Equations for the development of significant costs are presented. (2) Passenger service costs which are defined as those which vary with the number of passengers aboard an aeroplane are enumerated. (3) Overhead costs in air transportation are also dwelled upon and it is concluded that these costs change their proportion to significant costs when the physical and performance characteristics of the aeroplane being considered change.

The marked effect on significant cost of varying aeroplane utilisation is brought out. Utilisation is also shown to be chiefly a function of trip length, with block speed, seasonal schedule variation and other factors being secondary functions.

The effect on significant cost of varying block speed either by increasing cruising power or improving aerodynamic efficiency is investigated for one type of transport aeroplane. Increased block speed obtained by increasing cruising power is found to increase significant cost very rapidly. Increased block speed obtained by improving aerodynamic efficiency is found to decrease significant cost appreciably and relatively large increases in aeroplane first cost are found to be justified if aerodynamic efficiency is improved. The adverse effect on significant cost of increasing trip length is investigated. The effect of changing specific fuel consumption is discussed.

It is pointed out that economic factors apart from those associated with fundamental aeroplane design and performance, such as interior arrangement, safety records, competition and general economic conditions, play the major role in the economic outcome of air transportation.
Recent Research on the Improvement of the Aerodynamic Characteristics of Aircraft
Authors: Relf Ernest F.
Published: August 2016

The object of the present paper is to draw attention to some of the recent researches which have had as object the improvement of the aerodynamic characteristics of aircraft. Such characteristics can be classified into two groups; those concerned with performance and those concerned with stability and control. In the former group come all those researches which aim at the reduction of drag, while in the latter group come those directed to the attainment of satisfactory stability and control in normal flight, as well as those concerned with the behaviour of auxiliary devices such as flaps and slots which are used under special conditions and in particular during landing and taking-off. The problems associated with flutter also belong to this group. The two groups may be broadly characterised by the words economy and safety.
Part II. The Engine Viewpoint
Authors: Nixon F.
Published: August 2016

The problem under discussion is one which concerns both aircraft and engine constructors to an equal degree. Yet although their interest in it is a common one, inevitably their viewpoints will be different. This is not to say, however, that their conclusions will clash, and I want to make it clear that in setting out my views, as those of an engine designer, I intend them to be complementary to those of Mr. Chaplin, with the hope that taken together, they will in so me measure help in leading towards a complete solution of the problem.
The Calculation of the Loads and Bending Moments in Rigid Jointed Frames with Special Regard to Variation in Section of Members
Authors: Morris J.
Published: August 2016

The main object of this paper is to put forward a routine method for taking acccount of the variation in section in the stressing of rigid jointed frames. The formulæ in general use which mainly apply to members of uniform section are suitably modified so as to be applicable to cases where members may be of variable section. The underlying feature of the method is to base the treatment of a rigid jointed frame on the properties of cantilevers loaded at their free ends. Certain deflection coefficients are involved and as shown may be found separately as required for each member. These coefficients may be computed either analytically or graphically. The importance of taking account of variation in section is brought out by practical examples. In certain cases it is shown that very considerable errors may arise if instead of having regard to the actual variable section a mean value is assumed as being sufficiently close from the point of view of the resulting loads. From experience already gained in the application of the method to an actual structure the labour involved is not much in excess of that for the case of the same structure with the sections averaged.

The method does not take end load deflection effects into account and an extension of the method to do this seems desirable. There are, however, many cases in which end load deflection effects are not serious, and in any case it seems useful to have a solution in which these are neglected in the absence of means for obtaining a more comprehensive analysis.
Some Factors Controlling the Development of Electrical Ignition of Aero Engines
Authors: Bairsto G. E.
Published: August 2016

The conditions in which the various parts of the ignition system of aero engines have to operate have during recent times become much more onerous than hitherto. Many of the developments which have occurred in modern engines have caused the emergence of new problems so far as the ignition system is concerned, and have made older problems which had been only partially solved, even more difficult. This paper presents a review of some of the more important factors which are involved, an account of how the problems which have arisen have been solved, and indications given of limitations which still exist in various directions.
Strength of Metals in the Light of Modern Physics
Authors: Gough H. J. , Wood W. A.
Published: August 2016

The strengths of the metals at present available to industry are of especial importance to the aeronautical engineer who is also in a position to appreciate the need for greatly improved materials, the absence of which often places restriction on much needed developments. Although the materials of the future may become available by the somewhat fortuitous development methods at present employed, it is undeniable that greatly accelerated developments would result if a correct understanding was obtained of the fundamental characteristics of the cohesion and fracture of metals, of which the former belongs to the field of the atomic physicist.

It has been found possible, for the first time, to show that failure under static and fatigue stressing is associated with changes in the crystalline structure which are identical. These changes are (1) a dislocation of the initially perfect grains into large components which vary in orientation from that of the internal grain by amounts up to about 2°,(2) the formation of “crystallites,” approximately 10-4to 10-5cm. in size, whose orientation varies widely from that of the original grains, and (3) the presence of severe internal stresses in the crystallites. At fracture, whatever the type of applied stressing, the whole of the specimen behaves to the X-ray beam as a medium of crystallites showing marked lattice distortion and oriented completely at random. X-ray diffraction methods are shown to distinguish clearly between the effects of the application of safe and unsafe ranges of stress; the first method that has been successful in this respect.

In order to show the relationship between the new work described and previous work dealing with the use of X-rays in studying the deformation characteristics of metals, a preliminary section of the paper deals with cold-rolling and drawing. A survey is also presented of the present position regarding strength and atomic structure, together with references to various theories regarding the imperfections of crystals as encountered in practice. An introductory section describes briefly the atomic structure of metals, as revealed by X-rays.
Metallurgical Problems of Aero Engine Manufacture
Authors: Gadd E. R.
Published: August 2016

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.
Aerodrome Design
Authors: Norman Nigel
Published: August 2016

The present paper is confined to matters concerned with the requirements for landing and take-off of aircraft at land aerodromes, that is to the landing area.

In the selection of sites the questions that arise are size and over-all gradients. In development of a selected site account must be taken of directions of landing, dimensions of flightways or runways, local gradients or undulations, nature of surface. Finally, to ensure safety of flight the site must be protected by zoning.

The subsequent problems of detailed layout, of civil engineering in construction, of control and equipment, and of design of administrative and terminal buildings, though susceptible of more popular treatment, come later in sequence. My first more detailed study is therefore devoted to what may be termed the aircraft's point of view as to what it would like in order to bring in and take out its load in the most economical manner.
New Results and Problems in Medical Stratosphere
Research
Authors: Strughold H.
Published: August 2016

Flight is the most 'perfect and unconstrained form of animal motion; it is also the most widespread, since it offers the most favourable conditions of survival in the struggle for existence. Animal species losing the power of flight, are an easy prey for their enemies, and speedily become extinct.

Man, having achieved the power of mechanical flight by technical skill, has now introduced the art of flying in his own struggle for existence, as abundantly proved by the history of the past thirty years. Research, and not engineering research alone, has stood in the forefront of this development: filling the rôle of the advanced reconnaissance unit in development, experimentation, and the tactical application of the power of flight.

Man, aircraft-borne, now flies higher (record altitude 17,000 m.), faster (speed record 755 km./h.), and farther (long-range distance record over 12,000 km.), than any other animal. This raises a query as to the effect of flight on the human organism.
The Flying Controls of the Aeroplan
Authors: Hill G. T. R.
Published: August 2016

The primary object of flying is movement over the surface of the earth in the shortest possible time, and thus it comes about that the performance of an aeroplane is that characteristic which commands greater attention than all others.
The Wing-Beat of Pigeon
Authors: Guidi G.
Published: August 2016

After some general remarks upon the constant flight characteristics of birds belonging to any given species, the author describes his method of obtaining, approximately, a cinematographic reproduction of three geometrical projections of the wing-beat. Dealing with one particular case he determines the trajectory in space of a pigeon's wing tip during an entire beat, and, also, the speed and acceleration reached by it.
The Forces on an Aerofoil at Very Low Speeds
Authors: Thom A. , Swart P.
Published: August 2016

The forces on an aerofoil have been measured at various angles of incidence for 0.5 < R < 2,000.

Below R = 2 the lift is found to be given approximately by :—

L, = (3/2) µlV sin 2x

and the drag at all angles of incidence tends to:

D = µlV.

An approximate theoretical estimate is also given of the effect of spacing, on the drag of a series of flat plates at R → o.
Note on Aircraft Structural Failures and Factors for Safety
Authors: Pardoe J. G. M.
Published: August 2016

The well-known maxim “ know your enemy ” is as sound in aircraft design as it is in war. Application of this, doctrine might perhaps modify the conclusions in Mr. Tye's interesting paper, “ Factors of Safety –or of Habit? ” published in the November issue of the Journal. He discussed design factors and strength requirements from the aspects of V-g records and of structural variation. The V-g records with very few exceptions have been obtained from aircraft which have not broken up.
Plane Braced Frames Loaded Perpendicularly to their Planes
Authors: Drymael Jean
Published: August 2016

Summary*

The article deals with the calculation of plane frames each bar of which is able to withstand flexion perpendicularly to the main plane. After having shown that the stress corresponding to the loads parallel to that plane is independent of the stress corresponding to the perpendicular loads, the author develops for this latter a method of resolution based on Cross’ principle. Fictitious supports are added to each knot and then successively removed, till the structure reaches the true form corresponding to the loading. A very important improvement of the original method—formerly not applied to a three-dimensional construction— consists in the use of adjustments, that is appropriate movements of parts of the structure as a whole.

The method proved to have many advantages: Difficulties independent of the degree of redundancy, no loss of accuracy between the beginning and the end of calculations, large number of verifications in the course of resolution, reliability of the results, easy understanding of the successive steps, possibility of simultaneous work for many contributors, and relative shortness of the amount of work required.
A Method for Determining the “Safe” Life of an Aircraft Wing From Fatigue Test Results
Authors: Kennedy A. P.
Published: August 2016

It is now the usual practice in Great Britain to estimate the “ safe ” life of an aircraft wing from fatigue tests which are carried out on specimens representing the more highly stressed portions of the tension boom or booms. Such tests are designed to produce a tensile load in the boom equal to that produced in steady flight, and superimposed on this, a small fluctuating load corresponding to that which would be produced by an up gust immediately followed by a down gust of the same magnitude.
A Practical Exercise on the Strength of Rigid-Jointed Frames
Authors: Morris J.
Published: August 2016

Recent contributions to the theory of structures with particular reference to the design of aeroplanes have dealt with the theory of frames in which the members are rigidly connected together at the joints; the object being to ascertain the degree of increase in strength of the individual members due to the restraint at their ends supplied by the contiguous members.

Briefly, when a member forms part of a rigid-jointed structure it acquires a rigidity arising from the rest of the structure. The amount of rigidity given by the rest of the structure may vary from zero end fixation to full encastreing.
Meteorological Sub-Committee. Aeronautical Research Committee. The Formation of Ice on Aircraft.
Authors: Noth H. , Polte W.
Published: August 2016

The main reasons why trouble due to ice formation on aircraft was not experienced so much in the earlier days of flying as now were two-fold, (a) The greatly restricted amount of flying done during the winter and (b) the absence of means whereby flight in cloud for any considerable length of time was possible.

The degree to which ice forms, however, differs widely. Since much depends on the relative speed of the aircraft, free balloons are practically excluded. In the worst case ice cannot form on such aircraft to the extent to which heavy glazed frost is observed on the ground, unless the balloon pilot is a very bad navigator and remains in the danger zone longer than would be required for the ground surface to be coated with glazed frost.
At High Altitude
Authors: Lanchester F. W.
Published: August 2016

In the present paper (Part II) the engine, and more broadly the power plant, is considered in its relation to altitude. The discussion hinges mainly on the question of supercharge. After a brief reference to the various types of supercharger the author opens the discussion on an ideal basis, in which the supercharger is supposed to be 100 per cent, efficient, and the atmosphere is treated as adiabatic, as was at one time supposed. Then the “International Standard Atmosphere” is introduced as modifying the conditions, and after that the question of supercharger efficiency is dealt with. The author treats this on the basis of a law of adiabatic type but with a different index, and shows that this treatment gives an efficiency varying from approximately 60 to 70 per cent, as a function of altitude.

The difficulties connected with supercharge as affecting temperature, having been made clear, the subject of inter-cooling between compressor and engine is dealt with at length with the aid of thermodynamic diagrams. Then the propeller is discussed, and the case for variable pitch made clear.

Finally, the subject of surface cooling is dealt with, applied both to the engine and to the inter-cooler.
The Future Scope of Propellers
Authors: Fairhurst L. G.
Published: August 2016

With the rapid advances made during the war in the power output of piston engines, together with the introduction of straight jet and gas turbine units, the time is very opportune to consider the future scope of the propeller as an efficient means of aircraft propulsion on the types envisaged for the future.

The aircraft designer has taken full advantage of these advances in power unit development by introducing aircraft with ever improving aerodynamic characteristics, thus enabling these increases in power to be utilized efficiently.

The propeller designer has been fully cognisant of these combined developments, and in meeting them has had to make rapid strides in research and development throughout the war period.

In examining the future scope of propellers it is as well to review first the rate at which aircraft and engine development has proceeded over the last six years, as this development would never have been achieved in this space of time had it not been for the intervention of war.
Aircraft in Relation to Petroleum Technology: Use for Survey and Transport
Authors: Hemming H.
Published: August 2016

The lecturer has been concerned with commercial air survey operations since their inception after the war, more on the organisation, finance and business side, rather than on the technical. It is therefore from the angle seen from the directing side that this paper is submitted. As certain technical aspects will be of interest to the Institution, they are referred to, in order that attention may be drawn to them. Through the courtesy of the firms responsible for manufacture, certain apparatus is exhibited which includes an air camera, the automatic pilot, and the contouring stereoscope. Certain technical experts have kindly promised to be available to answer questions or to demonstrate apparatus, and certain individuals and firms have been good enough to lend photographs and slides. Acknowledgment for such assistance will be made in the reply to the discussion.
The Corrosion and Protection of Magnesium and its Light Alloys
Authors: Bengough Guy D. , Whitby L.
Published: August 2016

The chemist regards magnesium as a highly reactive metal for such reasons as the inflammability of its powder or foil in air, its active displacement of hydrogen gas from many aqueous chloride solutions and its position near the reactive end of the electrode-potential series. All these suggest that the metal would be unsuitable for constructional engineering. Yet engineers use alloys, rich in magnesium, up to 98 per cent. of the metal, for an increasing number of services, although the alloying elements do not, as a rule, greatly cut down, and may even increase, the corrosion rate. Their industrial use is possible because the liability to corrode, reckoned over a reasonably prolonged period, is not a definite property of a metal such as conductivity which is subject only to relatively small changes with alteration of environment, but is highly specific to metal-liquid and metal-gas systems. Moreover, these systems may undergo important changes with time owing to the intervention of films of corrosion products, and the rate of attack may be governed by the physical characteristics of these films which will vary with the adjacent liquid and gases. Thus in stagnant caustic alkalies magnesium may be reckoned as almost incorrodible because of the intervention of a film of hydroxide of the self-healing type which, in these conditions, is highly impervious to magnesium ions; but in the presence of alkali chlorides the corrosion product is physically different and rapid corrosion occurs. Many dilute acids attack magnesium rapidly but hydrofluoric acid scarcely at all, no doubt owing to the formation of a protective film of fluoride.
Airship Development Abroad
Authors: Booth R. S.
Published: August 2016

Last year I was fortunate enough to visit Germany and America at the kind invitations of Dr. Eckener and Admiral Moffett, and I hope that a short description of the development abroad will be of interest.

I propose to devote the short time at my disposal to these two countries, as, although France is still building non-rigid and semi-rigid airships for naval work and Russia has embarked on a most extensive airship programme, I think that the recent developments and improvements of the rigid type airship will be of more interest.
Note on the Application of Berry Functions to the Determination of Initial Stress
Authors: Dumbrill W. E.
Published: August 2016

The purpose of this note is to point out that in certain simple cases an immediate solution of the problem of finding- an initial stress is provided by an inverse application of the functions tabulated by A. Berry in his work on the generalised theorem of three moments.
The Hydrodynamics of Marine Aircraft
Authors: Lower J. H.
Published: August 2016

In considering the design of marine aircraft, viz., flying boats and
seaplanes, an entirely separate and additional subject is brought in for
investigation, and upon which there would appear to be much reserve as to
definite formulations and data, etc. This subject, which I prefer to entitle
“Hydrodynamics,” can become, besides interesting and absorbing, certainly
most deep in its complexity, and it is realised only too well by those
actually engaged in such investigations, the more that time passes and
experience is gained.