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Article
Publication date: 1 February 1960

P.F. Richards

By application of the analytical method to a wide range of current aircraft types an approximate form of the method is developed for the quick estimation of tail load maxima and…

57

Abstract

By application of the analytical method to a wide range of current aircraft types an approximate form of the method is developed for the quick estimation of tail load maxima and associated torques during the checked manoeuvre and the same is also confirmed for the unchecked manoeuvre of Ref. (3). Numerical values of critical elevator actions to be associated with the airworthiness design case are considered and hence, from a comparison with the approximate method, the limitations of the present empirical approach given in British and American civil airworthiness regulations are brought to light.

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Aircraft Engineering and Aerospace Technology, vol. 32 no. 2
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 January 1960

P.F. Richards

The general reasons for considering a fresh approach to the calculation of air‐worthiness design tail loads and associated torques due to elevator‐induced pitching manoeuvres are…

86

Abstract

The general reasons for considering a fresh approach to the calculation of air‐worthiness design tail loads and associated torques due to elevator‐induced pitching manoeuvres are discussed. Then follows a description of the manoeuvre itself, elevator actions to be assumed, and the proposed method of calculating the various response quantities. The analytical treatment of Czaykowski given to the unchecked manoeuvre is extended to cover the checked case in Appendix I, Part III and a comparison is made of the two types of manoeuvre. The application of the work to auto‐pilot feed‐back failure causing hunting of the elevator control is also dealt with. The effect of aircraft size, weight, e.g. position, forward speed and altitude on the various response quantities are discussed, with particular emphasis on the importance of the manoeuvre margin. To avoid possible confusion of terms the two types of elevator‐induced manoeuvre mentioned above and discussed in this paper are defined as follows:

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Aircraft Engineering and Aerospace Technology, vol. 32 no. 1
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 March 1960

P.F. Richards

This Part presents Appendices I and II which deal, respectively, with the theoretical analysis of the checked manoeuvre and a new simplified method of determining flight loads to…

45

Abstract

This Part presents Appendices I and II which deal, respectively, with the theoretical analysis of the checked manoeuvre and a new simplified method of determining flight loads to cover all pitching manoeuvres, in a form suitable for amendment of civil airworthiness regulations. The latter method also considers additional design cases, including the loading conditions arising from the malfunctioning of an anto‐pilot in pitch: a specimen calculation is also given.

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Aircraft Engineering and Aerospace Technology, vol. 32 no. 3
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 December 1964

I.I. McNaughtan

The methods of bird impact testing or aircraft transparencies are discussed and a review is made of tests on aircraft transparencies and transparency materials. The review…

48

Abstract

The methods of bird impact testing or aircraft transparencies are discussed and a review is made of tests on aircraft transparencies and transparency materials. The review includes the effects of temperature, of mounting and of the use of compound material screens. The validity of present design parameters are examined and proposals on both design parameters and test methods are presented.

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Aircraft Engineering and Aerospace Technology, vol. 36 no. 12
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 December 1909

In the Annual Report of the General Purposes Committee of the Middlesex County Council for the year ending March 31, 1909, it is stated that inquiries were made as to the action…

114

Abstract

In the Annual Report of the General Purposes Committee of the Middlesex County Council for the year ending March 31, 1909, it is stated that inquiries were made as to the action taken under the Dairies, Cowsheds, and Milkshops Orders of 1885 and 1899 by the thirty‐six district councils in the county, the object of such action being the detection of cows suffering from tuberculosis of the udder. It might be thought that by this time the necessity for putting these orders into force had been thoroughly proved. The Royal Commission on Tuberculosis made a definite statement to the effect that milk derived from tuberculous cattle is one of the principal causes of tubercular disease in the human subject, and, apparently there seems to be some disposition on the part of local authorities to make tuberculosis notifiable. The Public Health (Tuberculosis) Regulations, 1908, which came into force at the beginning of 1909, require that all cases of pulmonary tuberculosis are to be notified to the sanitary authority if the patients are receiving treatment from the Poor Law medical officers. Large sums are spent every year throughout the country on the upkeep of sanatoria with the object of curing cases of tubercle, if possible, but, in any case, of alleviating the sufferings of those afflicted with tuberculosis. On all sides, in fact, it is now recognised that the most energetic measures are necessary in order to combat this terrible disease. It appears from the figures given in the Report referred to that in twenty‐three out of the thirty‐six districts. “No veterinary examinations of cows were made on behalf of the local authorities!” The statement is not made the subject of comment, but we hardly think that the county authorities can regard the results of their enquiry as satisfactory. The Report was apparently presented to the County Council on July 22 last, so that up to that time, at least, it would seem that these twenty‐three districts, in a county with about one million inhabitants, are governed, so far as sanitary matters go, by people who consider themselves qualified to hold opinions diametrically opposed to those held by experts and based on the best scientific evidence at present available.

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British Food Journal, vol. 11 no. 12
Type: Research Article
ISSN: 0007-070X

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Article
Publication date: 1 September 1909

In the days of our childhood we were told that the process of picking tea in China involved a preliminary purificatory ritual on the part of the picker. Thus, he ate no fish…

85

Abstract

In the days of our childhood we were told that the process of picking tea in China involved a preliminary purificatory ritual on the part of the picker. Thus, he ate no fish, indulged in baths, and dressed himself in clean clothes as essential preliminaries before pursuing his occupation. This may have been true so far as the tea that was to be consumed by the Chinese went. So far as this country was concerned, it is on record that somewhere about the year of grace 1850 the ingenious Celestial was sending us consignments alleged to contain silkworm‐dung faced with tea‐dust and a little Prussian blue, sand, and gum, and so forth, a decoction of this being drunk by certain inhabitants of this happy land under the firm belief that they were partaking of the “cup that cheers but not inebriates.” Such frauds were possible, as at that time but little attention had been paid to the subject of food chemistry, and no attention at all to the kind of food that was being eaten by the people of London and elsewhere. The subject of food was chiefly dealt with from the point of view of the requirements of the inland revenue, and so long as the Government obtained the duty that was demanded, but little heed was paid to the quality of the product taxed. Very recently we have had arriving at the docks a carge of foods from Hankow, China, consisting largely of frozen pigs. We are assured that these redoubtable porkers have been fed on rice, and while alive have been carefully tended. It is not stated that they were fed from golden troughs, or that they were slaughtered by, say, members of the Chinese aristocracy, but it is stated and assumed that they are all that any self‐respecting Englishman can possibly desire. A point in their favour is also made of the cheapness of the pork yielded by them. At the present time our food is nothing if not cheap, and “cheap food” has become a party cry whose success depends on the obsession of the minds of a large number of ill‐informed persons with the idea that the only attribute of a food which is worthy of consideration is its cheapness. The fact that we are receiving foodstuffs of the nature of meat from China is one that demands special and more serious consideration from the authorities in view of its possible prejudicial influence on public health, and the important changes that may take place in the nature and origin of our meat supplies. The consignment in question consists of game of various kinds, eggs, ducks, and pork. About 4,600 frozen pig carcases were unloaded. It is asserted that the pigs were fed on rice, or at all events on clean food, and there seem no grounds for disbelieving the truth of this statement; but the increase in this trade which is looked for from those financially interested in it does not necessarily mean that the goodness of future consignments is assured. The fact that the trade may greatly develop makes it difficult to see how a proper supervision can be maintained over the Chinese farmers who will presumably furnish the material of future consignments. Inspection in China is, however, imperatively demanded in the interests of public health on this side. Only a small proportion of the consignment we refer to has been put on the market up to the present, and this was subjected to a very careful and thorough inspection at this end before it was put on the market. The process of inspecting every carcase that may be landed is one that from the mere amount of time and labour involved presents serious difficulties, and the thawing process necessarily leads to a certain amount of deterioration. But if the trade in Chinese pork increases, and the resources of China to supply pigs to the world's markets are practically illimitable, we do not see how it will be possible to adequately inspect every consignment that comes across, while on the other hand no country requires more careful looking after than China in this respect. Inspection on the other side must apparently be left in the hands of the exporters, a most undesirable course to adopt, and one that should therefore not be encouraged. It need hardly be pointed out that the Chinese authorities can or will do nothing in the matter. For a system of inspection to be thorough and adequate, and such inspection is absolutely necessary in this case, it is needful to have inspectors who are experts at their work, capable of exercising independent judgment, and who are above suspicion. It is hopeless to expect to find such people among the ranks of the ordinary Chinese. The farmers whose stock and premises are to be inspected must also be people with some elementary notions of what is required of them. It need hardly he pointed out that no such state of affairs exists in China, and indeed, under present circumstances, is unthinkable, nor is it right that we in this country should run risks while a system of adequate inspection is worked out; in other words, that we should educate the Chinese farmer for his own benefit while running risks ourselves. It is stated that the stockyards and plant are well adapted for the work they have to do, and this we readily believe, but in an Oriental country in which there are no such things as health laws in existence, and where each man in this respect may do very much as seems right in his own eyes, the fact that we are obtaining from it an important article of food wherewith to feed large numbers of our poorer population is not one that can be viewed without serious apprehension as to the possible consequences. Stress has been laid on the fact that the pork is cheap, and that when an adequate system of inspection has been devised, the complete thawing out of the consignment will be no longer necessary and that Chinese pork will rank with the meat supplies that we obtain from the colonies. We have heard of the Greek Kalends, and it is possible that by the time they arrive the Chinese pig breeder and coolie will be a sufficiently cleanly person to be trusted with matters of this sort, but until that time does arrive we most strongly dissent from any line of action that would tend to shift any responsibility on to his shoulders. The pig is a dirty feeder, and the Chinese variety of the genus sus has the fullest opportunity for indulging his propensities for filth. He is also an animal peculiarly liable to various forms of disease of which swine fever is not the least objectionable. The care that is taken by the local authorities in this country regarding swine is sufficient evidence of this. But to make the British farmer conform to certain regulations while permitting pigs to be imported from China where no such regulations, or indeed, any at all, are enforced, seems to us to be the limit of hardship and absurdity. Sir PATRICK MANSON in the year 1881, at the request of the Chinese Government, made a careful examination of the bazaar pigs in Amoy. As a result of this examination he came to the conclusion that the flesh of such pigs was not sufficiently healthy to allow of its being safely eaten by Europeans at least. Though the proportion of pigs affected by Trichina spiralis was about 1 per cent., his conclusion was that with pork “cooked as the natives cook it, there can be little danger, but a roast leg of pork cooked in foreign style would certainly be a most dangerous dish.” The method adopted by natives was to cut the pork into small pieces and very thoroughly cook it. These were bazaar pigs, and of Amoy, which is far south of Hankow, but the bazaar pig in Hankow is probably not very different to his southern brother, and the conditions now in China are probably not much altered for the better since 1881. The pigs for the English market must be obtained from native breeders, and unless these breeders exercise unusual care in the feeding and housing of their stock, it is unlikely that any somewhat perfunctory system of inspection will do much towards‐mitigating the danger arising from The consumption of their pork It may be remarked that no people are more conservative than the Chinese, and to expect a Chinese peasant to radically alter his method of treating his stock, for reasons that he is entirely unable to appreciate, because there happens to be a market in England for the pork is really expecting too much. Nor does it seem that a consular invoice would be any real remedy. The time for insisting on consular invoices would probably be at the end of another series of “revelations,” and moreover, to attempt to make a consul professionally responsible for the soundness of large quantities of such pork, would be to impose a strange burden upon him.

Details

British Food Journal, vol. 11 no. 9
Type: Research Article
ISSN: 0007-070X

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Article
Publication date: 1 July 1940

THIS issue opens the new volume of THE LIBRARY WORLD and it is natural that we should pause to glance at the long road we have travelled. For over forty years our pages have been…

38

Abstract

THIS issue opens the new volume of THE LIBRARY WORLD and it is natural that we should pause to glance at the long road we have travelled. For over forty years our pages have been open to the most progressive and practical facts, theories and methods of librarianship; our contributors have included almost every librarian who has held an important office; and we have always welcomed the work of younger, untried men who seemed to have promise— many of whom have indeed fulfilled it. In the strain and stress of the First World War we maintained interest and forwarded the revisions in library methods which adapted them to the after‐war order. Today we have similar, even severer, problems before us, and we hope to repeat the service we were then able to give. In this we trust that librarians, who have always regarded THE LIBRARY WORLD with affection, will continue to support us and be not tempted because of temporary stringency, to make a victim of a journal which has given so long and so independent a service.

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New Library World, vol. 43 no. 1
Type: Research Article
ISSN: 0307-4803

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Article
Publication date: 1 January 1900

The necessity of standards of purity for certain kinds of agricultural produce being now recognised by the new Adulteration Act—4, (1)—no apology is needed for attempting to bring…

66

Abstract

The necessity of standards of purity for certain kinds of agricultural produce being now recognised by the new Adulteration Act—4, (1)—no apology is needed for attempting to bring the application of the principle into actual practice. Some few standards have already been generally adopted, and the legalization of limits relating to many of those substances with which the Adulteration Acts deal would undoubtedly be welcomed.

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British Food Journal, vol. 2 no. 1
Type: Research Article
ISSN: 0007-070X

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Article
Publication date: 1 December 1964

E.G. Barber

Broad statistics or the incidence and cost of windscreen panel failures are given. The implications of these statistics are discussed with particular regard to the inability to…

68

Abstract

Broad statistics or the incidence and cost of windscreen panel failures are given. The implications of these statistics are discussed with particular regard to the inability to predict with any degree of certainty the time between installation and failure. Failures occur not only at random points in a time scale but also at any point on the airline's routes. If improvement in reliability is not economically attainable then compensation must be gained in ease and speed of replacement. The designer must make a realistic assessment of achievable reliability. The result of this assessment in dictating the need for ease of replacement may well be the controlling factor in the installation design.

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Aircraft Engineering and Aerospace Technology, vol. 36 no. 12
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 December 1964

W.E. Pryor

One of the main factors contributing to the effectiveness of the Royal Air Force is the quality of its equipment. To be most efficient the equipment should have the highest…

60

Abstract

One of the main factors contributing to the effectiveness of the Royal Air Force is the quality of its equipment. To be most efficient the equipment should have the highest possible performance coupled with complete reliability. Any departure from this standard of reliability must be compensated for by economy in maintainability. The high and unacceptable failure rates experienced by the Royal Air Force are discussed as are the effects on aircraft availability, mission success and flight safety. Other serious aspects are the consumption of spares, their replacement and the financial costs involved. Some failure patterns in different aircraft environments are discussed and the cause and effects of failures are examined, together with the modifications which have taken place. The paper concludes with a statement on the reliability and maintainability requirement which the Royal Air Force must have if it is to provide the maximum national insurance with its weapon systems.

Details

Aircraft Engineering and Aerospace Technology, vol. 36 no. 12
Type: Research Article
ISSN: 0002-2667

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