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At perhaps all levels of education, strong leadership skills are often equated with the ability to engage in critical thinking, and effective oral and written communication. The purpose of this study was to identify the self-perceived expansion of animal health interns’ leadership, critical thinking and communication competencies using the University of Florida – Engagement, Cognitive Maturity, and Innovativeness (UF-EMI) and Leadership Skills Inventory (LSI) assessments. For the UF-EMI, the total mean score of the pre-critical thinking disposition of all interns was 104.73; post-critical thinking disposition was 114.46, an increase of 9.73. Results of the LSI indicate just 70% accept who they are and don’t see themselves as good listeners.

A NUMBER of attempts have already been made to present a simple and easily understood account of wing flutter 1,2,3,4,5,6, but it appears that the subject is still obscure and difficult to many. Accordingly another elementary presentation of the subject is given in this paper, and the problem is approached in a new way. Emphasis is placed on explaining how flutter can happen; that is, on the physical mechanism by which an aeroplane wing can become a species of air engine and extract energy from the passing air. This explanation is greatly helped by experiments with a mechanism which has been called the “flutter engine”, consisting of a rigid aerofoil so arranged that when placed in an airstream it can oscillate and drive a flywheel.

THE paper reviews the problem of the influence of the walls of a closed tunnel in increasing the velocity in the neighbourhood of a model under test. It is shown that, for a perfect fluid, considerations of continuity suffice to establish an exact value of the mean interference velocity for any cross‐section of the tunnel. This mean interference velocity is expressed in terms of the perturbation velocity which would be caused by the same model in the absence of the walls. The linearized theory of subsonic compressible flow is applied and it is shown that the interference velocity for a small two or three dimensional model is increased in proportion to l/β3, where β=√(l—M2) and M is the Mach number. Interference caused by a body with a long parallel middle body, the influence of the wake from a model and of the boundary layer on the tunnel walls are briefly considered.

THE object of this paper is to put forward a family of aerofoil profiles which is sufficiently comprehensive to meet all practical requirements and which has the merit that the ordinates of the profiles can be very easily calculated. The profiles are not of the kind for which the irrotational flow patterns can be derived with special ease, but this is not considered to be a real disadvantage.

Although this volume has only just come to hand it bears the date 1938 and it is, therefore, not surprising that most of the contents are considerably out of date. The book, which is written in French, begins by giving a general description of the wind tunnel at the Ecole Polytechnique at Bucarest. The general layout of the wind tunnel is very similar to that of the compressed air tunnel at the N.P.L. but the tunnel works with air at normal atmospheric pressure and the main structure is built of wood. The exterior casing of the tunnel is in effect an independent building exposed to the weather and takes the form of a horizontal octagonal prism with truncated pyramidal ends. The working section is 1·5 metres in diameter and a driving motor of 40 kw. gives a top speed of 46 metres per second or very roughly 150 ft. per second. Results of tests on a considerable variety of Joukowski aerofoils carried out at a Reynolds number of a little below half‐a‐million are given in the report. On account of this low Reynolds number and of the fact that the sections are not of types now used in practice, the data will be of little interest to the aircraft industry. One minor point of terminology which appears to be worthy of comment is that profit a didre means a profile having a finite trailing edge angle, the idea being that there is a dihedral angle between the tangent planes at the trailing edge.

The purpose of this paper is to examine whether the improvements in technology that enhance community understanding of the frequency and severity of natural hazards also increased the risk of potential liability of planning authorities in negligence. In Australia, the National Strategy imposes a resilience-based approach to disaster management and stresses that responsible land-use planning can reduce or prevent the impact of natural hazards upon communities.

This paper analyses how the principles of negligence allocate responsibility for loss suffered by a landowner in a hazard-prone area between the landowner and local government.

The analysis in this paper concludes that despite being able to establish a causal link between the loss suffered by a landowner and the approval of a local authority to build in a hazard-prone area, it would be in the rarest of circumstances that a negligence action may be proven.

The focus of this paper is on planning policies and land development, not on the negligent provision of advice or information by the local authority.

This paper identifies the issues a landowner may face when seeking compensation from a local authority for loss suffered because of the occurrence of a natural hazard known or predicted to be possible in the area.

The paper establishes that as risk managers, local authorities must place reliance upon scientific modelling and predictive technology when determining planning processes to fulfil their responsibilities under the National Strategy and to limit any possible liability in negligence.

When one is presented with a book having such a very broad title as ‘Introduction to Aeronautics’ one does not know exactly what to expect. But one looks for a broad treatment of the subject and not merely a treatise on one particular aspect. What one does find in this instance is an introductory treatise on some non‐structural aspects of the design of aeroplanes and rotating wing aircraft, together with some sketches of more fundamental matters. The precise contents can be judged from the titles of the eight chapters, which are: Basic Concepts; The Power Unit; Drag and Performance Estimation; Flaps, Take‐Off and Landing; Control and Stability; Wind‐Tunnel and Flight Testing; Flight Manoeuvres; Load and Pressure Distribution; Rotating Wing Aircraft. There is an appendix corresponding to each chapter. In his ‘Explanatory Note’ the author states ‘In the chapters the matters dealt with are treated only to the extent required for a practical application, the proofs of formulae being usually omitted. In the appendices selected matters are further expounded, and additional information and references to published Reports are given.’ And in the Preface he says, ‘I trust… that the contents and the method of presentation will be found acceptable by the aircraft technician and draughtsman, and by the student of aeronautics also’. These sentences explain very adequately the intention of the author and the scope of the book, while indicating its severe limitations.

This paper continues the theme of the opening Part I by analysing a number of problems designed to illustrate some particular aspects of the general theory. Three are concerned with thermal stresses and the last applies inter alia the theorems on maxima and minima to find lower and upper bounds to the St Venant torsional stiffness of a thin solid section.

Flutter is a species of oscillatory instability affecting parts of aircraft, such as their wings. However, in as much as an aircraft is a single system, it would always be more accurate to say that flutter is an oscillatory instability affecting an aircraft as a whole. There arc, of course, many kinds of oscillatory diseases which afflict aeroplanes and other aircraft, but the flutter disease is characterized by the feature that both aerodynamic actions and distortional oscillations of the structure play an essential part. Thus, if an aeroplane could be made rigid it would not flutter. Needless to say, it is quite impossible to make an aeroplane, or indeed any other structure, strictly rigid but it is true that increasing the structural stiffness is one of the basic methods for avoiding flutter troubles, a fact duly insisted upon by the Airworthiness Authorities in all countries. Likewise, an aeroplane would not flutter if it were projected in a vacuum so that the aerodynamic actions were annulled, but then the sustaining force would also be absent. Both distortion and aerodynamic actions play a part in many kinds of oscillation other than flutter and several of these, such as ‘snaking’, fall'within what is regarded as the domain of ‘stability and control’. However, in such oscillations the structural distortions are not essential for the occurrence of instability.

THE Accidents Investigation Sub‐Committee of the Aeronautical Research Committee has issued a detailed technical report on the accident to the Junkers F.13‐type aeroplane G‐AAZK which occurred at Meopham, Kent, on July 21, 1930. The report, which fills ninety‐two pages, gives a complete account of the researches and technical investigations that were made at the instigation of the Sub‐Committee, much of which is of great technical interest. It is impossible here to do more than give a brief summary of the circumstances of the accident and the inquiries which led to the rejection of a number of theories of the cause, leading to the final conclusion that it was due to a phenomenon called “Buffeting,” which is defined as “an irregular oscillation of the tail unit, in which the tail‐plane bends rapidly up and down and the elevators move in an erratic manner.” It is caused by the eddies given off by the wings at large angles of incidence and is, the Sub‐Committee state, quite distinct from flutter, which, in the case of machines of the Junkers F.13‐type would develop only at speeds above 250 m.p.h.