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Advanced design main rotor blades — providing a major leap in performance through the latest technology — have been flown for the first time at the Yeovil base of Westland Helicopters.

Space tourism is often represented as an extended version of tourism on the Earth, with tourists experiencing relaxed and trouble-free experiences. But parallels between travel on the Earth and in outer space are misleading. The latter raises major issues concerning power-relations between passengers, pilots, and ground control. Who has the power in space tourism and how is this power exercised? The literature underestimates potential dangers to the human body. These include short- and long-term risks stemming from microgravity, exposure to radiation, and rapidly changing switches between day and night. These problems further undermine the popular image of space tourism as a wholesome and joyous practice. Space tourism may well be a very expensive way of achieving ill health.

This paper aims to propose a methodology for a safety and reliability assessment for the conceptual and preliminary design of very complex and disrupting innovative systems like trans-atmospheric vehicles. The proposed methodology differs from existing ones because it does not rely on statistical data at aircraft-level but exploits the statistical population at components-level only. For the sake of clarity, the paper provides some preliminary results of the application of the methodology at system level. The example deals with the safety and reliability assessment of a very complex propulsion system aimed at guaranteeing vertical take-off and landing capabilities of a suborbital vehicle.

The proposed methodology is strongly based on a systems engineering approach. It exploits safety and reliability assessment analyses which have already been developed in both aeronautical and space engineering domains, but it combines them in an innovative way to overcome the lack of statistics at aircraft level. The methodology consists of two different steps: a qualitative top-down process, allowing a functional and physical decomposition of the transportation system and a following quantitative bottom-up approach, which provides the estimation of system-level reliability and safety characteristics starting from the statistical estimation of the components’ characteristics.

The paper presents a new methodology for the preliminary reliability and safety assessment of innovative transportation systems, such as hypersonic transportation systems. The envisaged methodology will overcome the poorness of statistical data that is usually affecting the conceptual design of breakthrough systems.

The paper shows the application of the articulated methodology to a limited case study. A complete example of application of the methodology to estimate safety and reliability characteristics at vehicle level will be provided in feature works.

The methodology has been proposed to be exploited in international research activities in the field of hypersonic transportation systems. Furthermore, a massive application of this approach would allow to create a database for the generation and the update of semi-empirical models focused on high-level estimations of reliability, availability, maintainability and safety (RAMS) characteristics. Moreover, the proposed safety assessment has been conceived to be fully integrated within a typical conceptual design process.

The existing literature about safety and reliability assessment at the early design stages proposes pure statistical approaches which are usually not applicable to highly innovative products, where the statistical population is not existing, for example, in the case of trans-atmospheric vehicles. This paper describes how to overcome this problem, through the exploitation of statistical data at components-level only through the combination of these data to estimate RAMS characteristics at aircraft-level thanks to functional analysis, concept of operations and typical safety assessment tools, like functional hazard analysis, failure mode and effect analysis, reliability block diagram and fault tree analysis.

A two‐dimensional mathematical model of flame spread and solid burning is presented. For the gas phase, it consists of variable density, fully elliptic Navier‐Stokes momentum, energy and chemical species mass equations. Combustion processes are treated according to a one‐step, finite‐rate, reaction. The solid phase model describes a porous cellulosic fuel for a range of thicknesses from the thermally thin to the thermally thick limit. Conductive and convective heat transfer takes place as the solid degrades, by two first order Arrhenius reactions, to volatiles and chars. Variations of solid phase densities account for fuel burn‐out. Effects of gas phase and surface radiation are also included. A steady formulation of gas phase equations with respect to the unsteady solid phase mathematical model is proposed, gas phase characteristic times being much shorter than those of the solid phase. The non‐constant density Navier‐Stokes equations are formulated in terms of vorticity and stream function, avoiding the pressure‐velocity coupling and, at the same time, the adoption of a sample‐fixed coordinate system allows unsteady flame spread processes to be simulated. The solution is computed numerically by means of an iterative, operator‐splitting method based on implicit finite‐difference approximations. Numerical simulations of the dynamics of flame spread over cellulosic solids are presented and extinction limits as a consequence of reduced rates of fuel generation are determined.

The purpose of this paper is to analyse how the food innovation strategies carried out by an Italian firm, Argotec, responsible for the development and supply of space food (SF) for European astronauts on the International Space Station (ISS), can also be applied to food suitable to be eaten on Planet Earth. This study aims at showing the relationship between SF innovation and terrestrial strategies directed at implementing this kind of food also on terrestrial tables.

This research focusses on a case study. The subject of the case study under analysis is Argotec, an internationally recognised Italian aerospace engineering company, dealing with research, innovation and development in various sectors, including engineering, information technology, system integration, small satellites and “Human Space Flight and Operations”. The company produces innovative SF for European astronauts performing long-duration missions on-board the ISS. Moreover, the SF is made available also for terrestrial beings as a solution for everyday eating necessities.

Argotec is characterised by strong innovation in terms of products and processes. Throughout the case study, the authors focus on the relationship between SF innovation and its terrestrial applications, since this company also manufactures products, traded under the brand “ReadyToLunch”, suitable for daily meals on Earth. Innovation applied to SF can thus offer advantages also for terrestrial daily meals and therefore help the company achieve other competitive advantages: as to the authors’ knowledge, this is a unique case.

This study also has some limitations, typical of the applied methodology. In relation to the interview technique, further interviews would be required in order to fully understand the end-user perspectives regarding the importance and interest of this kind of “ready-to-eat” food.

Practical implications relate to astronauts and to terrestrial consumers. For astronauts, SF is not any more intended only to satisfy humans’ basic needs, and to provide the necessary nutrients during space missions, but has become an important factor in the quality of life in space. For terrestrial consumers, SF may represent a healthy, tasty and nutritious “ready-to-eat” choice: single courses for the main meals and snacks for a break.

This research fills a gap in literature: to the authors’ knowledge, this is the first paper presenting a case study on a company responsible for the development and supply of SF for European astronauts on-board the ISS, as well as encouraging the consumption of SF by terrestrial beings, as an ordinary “ready-to-eat” lunch/dinner.

The influence of buoyancy forces on oscillatory Marangoni flow in liquid bridges of different aspect ratio is investigated by three‐dimensional, time‐dependent numerical solutions and by laboratory experiments using a microscale apparatus and a thermographic visualisation system. Liquid bridges heated from above and from below are investigated. The numerical and experimental results show that for each aspect ratio and for both the heating conditions the onset of the Marangoni oscillatory flow is characterized by the appearance of a standing wave regime; after a certain time, a second transition to a travelling wave regime occurs. The three‐dimensional flow organization at the onset of instability is different according to whether the bridge is heated from above or from below. When the liquid bridge is heated from below, the critical Marangoni number is larger, the critical wave number (m) is smaller and the standing wave regime is more stable, compared with the case of the bridge heated from above. For the critical azimuthal wave number, two correlation laws are found as a function of the geometrical aspect ratio A.

The purpose of this paper is to present an investigation of the effect of different gravity conditions on the penetration mechanism using the two-dimensional Distinct Element Method (DEM), which ranges from high gravity used in centrifuge model tests to low gravity incurred by serial parabolic flight, with the aim of efficiently analyzing cone penetration tests on the lunar surface.

Seven penetration tests were numerically simulated on loose granular ground under different gravity conditions, i.e. one-sixth, one-half, one, five, ten, 15 and 20 terrestrial gravities. The effect of gravity on the mechanisms is examined with aspect to the tip resistance, deformation pattern, displacement paths, stress fields, stress paths, strain and rotation paths, and velocity fields during the penetration process.

First, under both low and high gravities, the penetration leads to high gradients of the value and direction of stresses in addition to high gradients in the velocity field near the penetrometer. In addition, the soil near the penetrometer undergoes large rotations of the principal stresses. Second, high gravity leads to a larger rotation of principal stresses and more downward particle motions than low gravity. Third, the tip resistance increases with penetration depth and gravity. Both the maximum (steady) normalized cone tip resistance and the maximum normalized mean (deviatoric) stress can be uniquely expressed by a linear equation in terms of the reciprocal of gravity.

This study investigates the effect of different gravity conditions on penetration mechanisms by using DEM.

Alternative energy sources and power generation techniques for long‐term space missions are gaining importance in recent years for future bases and colonies on the Moon or Mars. Current technologies used for manned or unmanned missions to the Moon or Mars use either solar panels (bulky, expensive/kilogram to space, and inefficient) or nuclear energy (extremely dangerous and unpopular). Enzyme based bio fuel cells can be used as alternative energy sources, but its survival depends on maintaining appropriate temperature and pressure in space. The purpose of this paper is to detail the concept design and development of a payload tank to house bio fuel cells for operations in space environment.

Details about the development of the design methodology for such housing are discussed. A full‐scale payload tank is designed to house a small biological fuel cell using space grade materials. Requirements analysis, design, validation, and manufacturing process are covered.

The outcome is a dimensionally optimized housing structure for housing biological fuel cells and maintaining the temperature and pressure for survival of the fuel cell.

The designed payload housing satisfies all the constraints and requirements. Furthermore, its advantages include scalability and modularity by virtue of using optimized design approach. The final product provides a planned procedure for designing larger housing for other missions.