Airlines are not able to conduct their businesses in the same way as other global transnational industries. They are inhibited by the foreign ownership restrictions in Air Services Agreements and national laws. Since the United Kingdom and the United States signed the first Bermuda agreement in 1946, the nationality clauses contained in virtually all bilaterals have limited the companies designated to provide services to those airlines owned and managed by nationals of the respective countries. A key reason why foreign ownership rules remain in place is that they protect national airlines. In doing so, they also limit the strategies available to governments whose carriers are in difficulties. The 57 years old bilateral system restricts the development of international air services, adversely affecting airlines and their users- travellers and the tourism and air freight industries. As time goes on, the rapidly changing air transport environment of privatisation, liberalisation and globalisation is forcing airlines to seek structural adjustments in order to survive in the new millennium. Airlines are asking to have more freedom for their strategies, in order to enhance their profitability. Pressures have been growing to ease the ownership rules contained in bilateral agreements to allow airlines greater commercial freedom. As there is no comprehensive research on the topic, this study aims to provide a detailed analysis of the impact of airline ownership rules. It will provide a point of reference for organisations like ICAO and nations to review the ownership issue in the future. This research starts with a review of the historical background, the current limitations in different countries and the pros and cons of ownership rules. It analyses how aviation markets have been influenced to date around the world and how governments and carriers have responded to these influences. It goes on to identify the main benefits and risks of foreign investment, and the motives for foreign investment in the EU and Asia- Pacific. It assesses the prospects for change in ownership rules under multilateral and plurilateral proposals, and develops a strategy for changing the current ownership rules. It concludes by predicting how airlines will react to such changes and makes suggestions for European Airlines in the Asia-Pacific region.

The limitations in en-route Air Traffic Control today are generally accepted as being the workload and performance of the controller. This method of operation is known as the 'manual control process'. The manual control process is an open loop form of control, that relies heavily on controller judgement and decision making. Future developments in ATC, that use twoway datalink, and integrate air and ground systems, are expected to be delayed. This leaves the manual control process to manage the projected growth in air transport demand. An analysis was carried out of the manual control process on two sectors at the London Area & Terminal Control Centre at West Drayton. Particular attention was given to understanding complexity, the functions that controllers perform, decision making and information sources. A systems approach was taken to the analysis and used multidisciplinary research techniques. The study used naturalistic data collection. Both the ground and airborne systems were reviewed, and developments found within them, that can benefit the control process. An analysis of incidents in en-route ATC was also conducted. Proposals are made that can support an enhanced control process. These were modelled, and the results indicated that reductions in controller workload are attainable. The changes to the control process involve more close control of the vertical plane, and improved and more precise information being made available to the controller. It is suggested that aircraft flight management systems are used as a control tool, and system requirements are proposed.

Nitrile rubbers (copolymers of butadiene and acrylonitrile) are widely used throughout the aerospace, automobile, construction and footwear industries. The useful properties of nitrile rubbers include excellent resistance to the action of oils, petroleum fuels and solvents, combined with good heat and abrasion resistance. These properties derive from the polar nature of the cyanide group on the polymer chain and rubbers with high oil resistance contain 40 - 50 mole % acrylonitrile. Unfortunately, at low temperatures the elastomeric properties of such rubbers are poor. One of the objectives of this work was to investigate whether the working temperature range of nitrile rubbers could be extended by chemicalmodification, in particular by grafting poly (tetrahydrofuran) (PTHF) onto the nitrile rubber. PTHF is a low melting, crystalline polymer with a glass transition temperature, Tg, of -84°C, above which it is rubbery. The polymerisation of THF can be initiated by the generation of suitable carbonium ions which attack the ethereal oxygen of the THF molecule forming an oxonium ion. Propagation occurs via this oxonium ion intermediate by a cationic, ring-opening mechanism. This 'living' polymerisation can be terminated by many nucleophilic reagents such as water, methanol, etc. In view of the polymerisation characteristics of THF, it can be grafted to a nitrile rubber backbone by two distinct methods. The first is a 'grafting from' technique, which involves initiation of the THF polymerisation from carbonium ion sites generated on the polymer backbone. In these experiments, described in Chapter 2, the parent rubbers were first functionalised by dihalocarbenation, bromination and allyl bromination, and on reaction with a suitable silver salt cationic centres were generated on the backbone. This method proved to be unsuitable for preparing well-defined graft copolymers of PTHF. The second process, a 'grafting onto' technique, involved a 'coupling' reaction between 'living' PTHF and functional groups previously attached to the nitrile rubber backbone. This method, which was finally chosen to prepare a range of graft copolymers of PTHF, is described in Chapters 3 and 4. One to 3 mole % of the diene residues in the nitrile rubber were first epoxidised then treated with HC1 to open the epoxide rings to yield chlorohydrin groups. The hydroxyl substituents functioned as terminators in a 'coupling' reaction with the 'living' PTHF to form a graft copolymer. Since polymerisation of THF at room temperature is fairly slow the lengths of the grafted chains could be controlled by monitoring the time from initiation to termination. The graft copolymers and precursors were examined by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and for solvent resistance. The DSC results show that grafting with PTHF reduces the Tg of low nitrile rubbers but has little effect on the Tg of high nitrile rubbers. This is believed to be due to a greater degree of phase separation of the PTHF component in the high nitrile rubbers. Consequently, the physical properties of these PTHF-high nitrile rubber grafts are not those of a homogeneous amorphous blend of the two components, TGA of the PTHF graft copolymers suggest that the PTHF graft destabilises the nitrile rubber to heat. However, PTHF is well known to be susceptible to hydroperoxidation and it is likely that thisc effect is attributable to peroxides rather than the PTHF chains per se. An antioxidant should be capable of inhibiting hydroperoxidation. Finally, the solvent resistance of the PTHF graft copolymers, especially from high nitrile rubbers, is lower than that of the original nitrile rubber.

Risk management is considered to be an application of general concepts in scientific management of a particular problem of exposure to risk of loss. It is concerned with identifying objectives, analysing the data regarding the nature of the problem, evaluating the pure risks deriving from the nature of the business and choosing or finding the most suitable method or methods of handling these risks; aiming to control them and their effects as well as minimizing the cost. The field of aviation has grown very quickly and developed faster in the last few years to reach the present level of operation and technology by introducing more advanced and higher capacity airliners. Therefore, aviation risks and their financial impact exhibit a number of distinguishing characteristics that raise problems for traditional risk management and insurance technique in dealing with such risks. The study reviews, analyses and classifies aviation risks and their characteristics as well as the major hazards involved in aircraft and their operation. The research undertakes to review the international conventions and agreements affecting air transportation and the limits of liabilities affecting those who operate airlines internationally in respect of death, injury or damage caused to passengers, baggage, cargo and third parties as well as safety and security of aircraft in the air and on the ground. It also studies and analyses the international jet airliner fleet, their accidents and their causes to provide a basis of choosing suitable risk levels in managing these risks.

No description available.

Hypothesis A modified brace position would help to prevent injury to some aircraft passengers in the event of an impact accident. Aim of Experiments To evaluate a modified crash brace position. Materials and Methods 1. Impact Testing Impact testing was performed at the RAF Institute of Aviation Medicine, Farnborough. Aircraft seats, mounted on a sled, were propelled down a track at an acceleration of 16G. A 50% Hybrid III dummy was used as the experimental model. Four dummy positions were investigated: upper torso either braced forwards or sitting upright and lower legs placed either forwards or rearwards. The impact pulses used were based upon guidelines defined in Aerospace Standard AS8049 which relates to the dynamic testing of aircraft seats. Transducers located in the head, lumbar spine and lower limbs of the dummy recorded the forces to which each body segment was exposed during the impact. These forces were compared for each brace position. 2. Computer Simulation A mathematical model was developed to simulate occupants kinematics during an impact aircraft accident. This was based upon MADYMO -a crash victim simulation computer programme for biomechanical research and optimization of designs for impact injury prevention. Results Impact testing revealed that the risk of a head injury as defined by the Head Injury Criterion was greater in the upright position than in the braced forwards position (p < 0.00 1). The risk of injury to the lower limbs was dependant in part to their flailing behaviour. Flailing did not occur when the dummy was placed in a braced legs back position. Computer simulation revealed that lower limb injury may result from the feet becoming entrapped under the luggage retaining spar of the seat ahead. Conclusion A modified brace position would involve passengers sitting with their upper torso inclined forwards so that their head rested against the structure in front if possible. Legs would be positioned with the feet resting on the floor in a position slightly behind the knee. This position differs from those previously recommended in that the feet are positioned behind the knee. This study suggests that such a position would reduce the potential for head and lower limb injury in some passengers given that only a single seat type and single size of occupant have been evaluated. Standardisation to such a position would improve passenger understanding and uptake. Such a recommendation should not obscure the fact that an occupant seated in a forward facing aircraft seat, restrained only by a lap belt is exposed to considerable forces during an impact accident. Such forces are capable of producing, injuries in the femur, pelvis and lumbar spine.

An experimental and computational study, motivated by the need to improve current understanding of blade flutter in turbomachinery and provide 3D test data for the validation of advanced computational methods for the prediction of this aeroelastic phenomenon, is presented. A new, low speed flutter test facility has been developed to facilitate a detailed investigation into the unsteady aerodynamic response of a turbine blade oscillating in a three dimensional bending mode. The facility employs an unusual configuration in which a single turbine blade is mounted in a profiled duct and harmonically driven. At some cost in terms of modelling a realistic turbomachinery configuration, this offers an important benefit of clearly defined boundary conditions, which has proved troublesome in previous work performed in oscillating cascade experiments. Detailed measurement of the unsteady blade surface pressure response is enabled through the use of externally mounted pressure transducers, and an examination of the techniques adopted and experimental error indicate a good level of accuracy and repeatability to be attained in the measurement of unsteady pressure. A detailed set of steady flow and unsteady pressure measurements, obtained from five spanwise sections of tappings between 10% and 90% span, are presented for a range of reduced frequency. The steady flow measurements demonstrate a predominant two-dimensional steady flow, whilst the blade surface unsteady pressure measurements reveal a consistent three dimensional behaviour of the unsteady aerodynamics. This is most especially evident in the measured amplitude of blade surface unsteady pressure which is largely insensitive to the local bending amplitude. An experimental assessment of linearity also indicates a linear behaviour of the unsteady aerodynamic response of the oscillating turbine blade. These measurements provide the first three dimensional test data of their kind, which may be exploited towards the validation of advanced flutter prediction methods. A three dimensional time-marching Euler method for the prediction of unsteady flows around oscillating turbomachinery blades is described along with the modifications required for simulation of the experimental test configuration. Computationalsolutions obtained from this method, which are the first to be supported by 3D test data, are observed to exhibit a consistently high level of agreement with the experimental test data. This clearly demonstrates the ability of the computational method to predict the relevant unsteady aerodynamic phenomenon and indicates the unsteady aerodynamic response to be largely governed by inviscid flow mechanisms. Additional solutions, obtained from a quasi-3D version of the computational method, highlight the strong three dimensional behaviour of the unsteady aerodynamics and demonstrate the apparent inadequacies of the conventional quasi-3D strip methodology. A further experimental investigation was performed in order to make a preliminary assessment of the previously unknown influence of tip leakage flow on the unsteady aerodynamic response of oscillating turbomachinery blades. This was achievedthrough the acquisition of a comprehensive set of steady flow and unsteady pressure measurements at three different settings of tip clearance. The steady flow measurements indicate a characteristic behaviour of the tip leakage flow throughout the range of tip clearance examined, thereby demonstrating that despite the unusual configuration, the test facility provides a suitable vehicle for the investigation undertaken. The unsteady pressure data show the blade surface unsteady pressure response between 10% and 90% span to be largely unaffected by the variation in tip clearance. Although close examination of the unsteady pressure measurements reveal subtle trends in the first harmonic pressure response at 90% span, which are observed to coincide with localised regions where the tip leakage flow has a discernible impact on the steady flow blade loading characteristic. Finally, some recommendations for further work are proposed

No description available.

This study examines the main problems associated with passenger survival and evacuation in survivable aircraft fire situations under current regulatory safety requirements and assesses current and alternative strategies to combat cabin fire, and assist evacuation, with a view to identifying a best alternative strategy. The technical and management findings associated with a research programme which was conducted into passenger smoke hood protection are then described. The survival/evacuation/pathology aspects associated with 10 selected accidents to public transport aircraft which involved fire are reviewed at the outset of this study in order to set forth the attendant problems of survival in such situations. The pathology and toxicological findings associated with these accidents are then discussed. The assembled information is then analysed with a view towards identifying the key problems inherent in survival and evacuation from aircraft fires, including those which stem from survivable in-flight fires. The current regulatory requirements and associated strategies relating to occupant survival/evacuation are then critically reviewed against the key problems identified. A review of alternative strategies is then conducted and an assessment made of technical potential, related cost-benefit data, problems still to be resolved and possible timescales for implementation. A'best-strategy'is then selected. The potential benefits of this strategy are then set forth in terms of its relevance to the survival/evacuation problems identified, associated cost-effectiveness, potential synergy with existing, and possible future, requirements and implementation timescale. A review of data on aircraft fires is then conducted, including that associated with the thermochemical characteristics of such combustion atmospheres and related effects on animals and humans. Using this data, the approach used to develop a set of acceptance criteria for aircraft passenger smoke hood designs is described. In addition, the way in which a challenge combustion atmosphere model was developed, and against which filter-type smoke hoods could be tested, is described. The organisation and implementation of a research programme to evaluate the performance capability of a range of breathable-gas and filter-type smoke hoods is then described in terms of the technical and management aspects, and the results set forth- Finally, the results of the study are analysed from both a technical and management perspective and appropriate conclusions and recommendations presented.

No description available.