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IT is indeed an honour to appear before you to address you on the subject “American Methods of Aircraft Production.” We in America have long held the Royal Aeronautical Society in high regard, amply justified by the excellence of its published papers and the example it has set in organisation and in the conducting of an aeronautical society. Indeed, a few years ago when several of us in America decided that we, too, should have an aeronautical society, we planned our own organisation very largely on yours. We are very much pleased that the relationship which has existed between your Society and the Institute of the Aeronautical Sciences in America throughout the brief career of the latter has been so close and friendly and I can assure you that we intend to do everything possible on our part to continue this highly desirable condition.

THE seventh annual meeting of the Institute of the Aeronautical Sciences had a somewhat different character from previous meetings, with greater emphasis on the instrumentation, meteorology and other problems of air transport technique and less emphasis on the more advanced phases of aerodynamics and structures. It is impossible to say whether this was accidental or the result of the fact that owing to extreme pressure on the research departments of the government and of the industry, and owing to the feeling that greater secrecy must be observed in view of the international situation, less of the really advanced research was disclosed. At any rate Mr. T. P. Wright, the retiring President of the Institute struck the key‐note of the meeting in an address in which he warned the United States that they were perhaps lagging in research behind European countries, who under threats of war were making feverish advances. “A few years ago,” Mr. Wright said, “the United States was well in the lead in research, development and production of aircraft,” a fact attested to by all who had the opportunity of visiting European countries at that time and of witnessing the scope of developments there. Little could be learned from abroad at that time. Recently, however, visitors abroad have witnessed a great change. Many huge aeronautical laboratories have been established and are occupied in intensive research investigations. Experimental development has likewise progressed. It is definitely established that the relative position of this country is reversed from 1934. We believe, however, that the situation is fully realized by governmental authorities and that American research will not lose its position in the van so readily.

The purpose of this paper is to study the prevalence of human learning in the order picking process in an experimental study. Further, it aims to compare alternative learning curves from the literature and to assess which learning curves are most suitable to describe learning in order picking.

An experimental study was conducted at a manufacturer of household products. Empirical data was collected in the order picking process, and six learning curves were fitted to the data in a regression analysis.

It is shown that learning occurs in order picking, and that the learning curves of Wright, De Jong and Dar‐El et al. and the three‐parameter hyperbolic model are suitable to approximate the learning effect. The Stanford B model and the time constant model led to unrealistic results.

The results imply that human learning should be considered in planning the order picking process, for example in designing the layout of the warehouse or in setting up work schedules.

The paper is the first to study learning effects in order picking systems, and one of the few papers that use empirical data from an industrial application to study learning effects.

This paper discusses how learning-by-doing (LBD) criterion can be used to evaluate the sustainability of supply chains. This paper assesses the impacts of teamwork on the LBD criterion. Besides, the effect of the internship of new labors on the LBD criterion is discussed.

The repeat of a task leads to a gradual improvement in the efficiency of production systems. LBD occurs by accumulating knowledge and skills in multiple periods. LBD can be used to study changes in the efficiency. Efficiency can be improved by accumulating knowledge and skills. In this paper, the LBD criterion is projected on learning curve (LC) models. Furthermore, the LC models are fitted to the supply chains. Each supply chain may have a unique LC model. A minimum difference is set between the current performance of decision making unit (DMU) and the estimated performance of DMU based on DMU's LC. Hence, a point in which the LBD occurs is determined.

This paper develops an inverse network dynamic data envelopment analysis (DEA) model to assess the sustainability of supply chains DMUs. Findings imply that the LBD criterion plays an important role in assessing the sustainability of supply chains. Furthermore, managers should increase the internships and teamwork to get more benefit from the LBD criterion.

For the first time, this paper uses the LBD criterion to assess the sustainability of supply chains given the LC equations.

THE eleventh annual meeting of the Institute was for the first time held simultaneously in three centres—in New York City at Columbia University, in Detroit at Rackham Educational Memorial, and in Los Angeles at the University of Southern California—from January 25 to 29. The purpose of the three simultaneous meetings was to minimize travel by executives and engineers from important war jobs in the present emergency. The same programme was offered at all three centres, papers being sometimes presented by proxies—experts in the same field as far as possible. In spite of the fact that attendance was divided between three centres, there was splendid representation at each place and a wide range of subjects was covered in the many papers. Naturally these were restricted more to analysis, and technology and information as to the latest design or production features of current aircraft or engines was withheld. The same ban applied to striking developments in accessories, instruments and armaments. All papers had to be approved by the Army or Navy and to be read substantially as written. While off‐the‐record discussions were permitted, these discussions were not made public. In particular there was a ban on comparisons between foreign and American materials, equipment or methods. The formula for control of comparison performance stated that the manufacturer's smooth curve calibrations and performance figures might be quoted, but no Wright field performance figures or data could be revealed. In spite of such restrictions a tremendous amount of valuable technical information was presented to the assembled engineers.

IN the 1940 Wilbur Wright memorial lecture on the future of British Civil Aviation Dr. Roxbec Cox has stated that the study of passenger convenience leads to consideration of over weather flying and that the study of improvements in safety leads to consideration of flutter prevention. He has stated also that all aviation authorities recognize the danger of flutter and warns that the chief danger to be guarded against in the future is a sense of security. It has, therefore, been thought worth while to examine the effect on wing flutter speed of flying at great heights. The effects have already been briefly considered by Williams, Pugsley and Duncan in this country and by Kassner and Fingado in Germany.

IN the recent lecture on U.S. Methods of Aircraft Production given by Mr. T. P. Wright before the Royal Aeronautical Society the methods shown for cutting duralumin plates will be of interest to many people. Perhaps a brief description of a simple arrangement for cutting small blanks, which has been much used in America, will also be of interest and use to some readers.

WHEN the Ministry of Aircraft Production drastically reduced the military aircraft programme in 1945, forecasts had to be made of the consequential reductions in labour requirements in the aircraft factories. During the drawn‐out build‐up period, and the period of relative stability in 1944, labour forecasts had been made with somewhat arbitrary adjustments, and not entirely without success, on a pro rata basis. With the end of the war in sight, the forecasters were faced with a programme that showed a reduction of something like 75 per cent in output to be achieved in the course of a few months. Could the pro rata assumption give labour forecasts even approaching the right order of magnitude?

In manual order picking systems, temporary workers are often employed to handle demand peaks. While this increases flexibility, it may hamper productivity, as they are usually unfamiliar with the processes and may have little experience. It is important for managers to understand how quickly inexperienced workers arrive at full productivity and which factors support workers in improving their productivity. This paper aims to investigate how learning improves the performance of order pickers, and how their regulatory focus (RF) and monetary incentives, as management actions, influence learning.

Data was collected in two case studies in controlled field-lab experiments and statistically analysed. This allowed evaluating the validity of hypotheses through an ANOVA, the calculation of correlation coefficients and the application of regression models.

A monetary incentive based on total order picking time and pick errors has a positive influence on order picking time, but not on pick quality. The incentive influences initial productivity, but not the learning rate. A dominant promotion-oriented RF increases the effect of the incentive on initial productivity, but it does not impact worker learning.

This study contributes to behavioral and human-focused order picking management and supports managers in setting up work plans and developing incentive systems for learning and productivity enhancement, considering worker RF.

This work is among the few to empirically investigate the effect of monetary incentives on learning in interaction with RF. It is the first study to investigate these concepts in an order picking scenario.

This study aims to investigate the dispositions of early career teacher educators as young academics toward sustainability and accountability for sustainability issues. Through their interpretations, concerns, awareness and ownership of sustainability, the study portrays how a global phenomenon is articulated specifically within the local context of teachers colleges in Turkey.

The study was designed as a survey, and the data were collected through a cross-sectional online questionnaire. The sample (n = 72) was limited, through purposeful sampling, to early career teacher educators teaching and being trained in well-established Turkish teachers colleges to become prospective faculty members of newly founded teachers colleges across the country. The data were analyzed primarily through quantitative methods. For the analyses, STATA software was used to perform descriptive and inferential statistics.

The general results indicated that the participants were highly concerned about sustainability problems. However, their concerns were not reflected to the same degree on their perceived awareness and ownership of education for sustainable development (ESD). Hunger and poverty, loss of biodiversity, climate change and epidemic diseases were all perceived to be urgent more in the global context. On the other hand, unemployment, refugees and terrorism were perceived to be locally urgent problems. Different agencies within the community were addressed to be accountable for different types of sustainability problems. The accountability for economic, environmental and societal problems were mainly placed on governments. Additionally, individuals/families and educators were held more accountable for environmental issues, while corporations and super powers were held more accountable for economic issues. As for societal issues, educators, individuals/families and non-governmental organizations were addressed to be more responsible.

The significance of the study is mainly twofold. If sustainable development is conceptualized with a futuristic viewpoint that attaches a great importance to next generations' needs, focusing on the dispositions of early career teacher educators as young academics is a reasonable way of addressing the current gaps and eliminating the future inefficacies. Building on the assumption that ESD would remain imperfect without the commitment of teacher educators who have the potential to bring changes in educational systems and shape knowledge and skills of future teachers, in turn future generations; this study becomes even more valuable as it includes specifically the academicians in the field of teacher education.