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The purpose of this paper is to present a novel hybrid engine concept for a multi-fuel blended wing body (MFBWB) aircraft and assess the performance of this engine concept.

The proposed hybrid engine concept has several novel features which include a contra-rotating fan for implementing boundary layer ingestion, dual combustion chambers using cryogenic fuel (liquefied natural gas [LNG] or liquid hydrogen [LH2]) and kerosene in the inter-turbine burner (in flameless combustion mode) and a cooling system for bleed air cooling utilizing the cryogenic fuel. A zero-dimensional thermodynamic model of the proposed hybrid engine is created using Gas Turbine Simulation Program to parametrically analyse the performance of various possible engine architectures. Furthermore, the chosen engine architecture is optimized at a cycle reference point using a developed in-house thermodynamic engine model coupled with genetic algorithm.

Using LH2 and kerosene, the hybrid engine can theoretically reduce CO₂ emissions by around 80 per cent. Using LNG and kerosene, the CO₂ emissions are reduced by more than 20 per cent as compared to the baseline engine.

The hybrid engine is being investigated in the AHEAD project co-sponsored by the European Commission. This unique aircraft and engine combination will enable aviation to use cryogenic fuels like LH2 or LNG, and will make aviation sustainable.

The MFBWB concept and the hybrid engine is a novel concept which has not yet been investigated before. The potential implications of this technology are far reaching and will shape the future development in aviation.

The future of the current family of wide‐bodied transports is examined in the environment of the changing world‐wide fuel supply situation. Synthetic hydrocarbon and cryogenic fuels are considered in the context of impact on airline fleets and their maintenance. The probability of the emergence of new technology aircraft, still utilising hydrocarbon fuel is considered in view of the possible shortening of their useful life by the introduction of cryogenic fuels. Possible effects on maintenance of the new technologies which would be included in such aircraft are discussed. Finally, the characteristics of the two most promising cryogenic fuels are compared and the effects of one of these fuels on fuel system design, maintenance, and service as well as facilities and equipment are reviewed.

A recent two‐line news item in the International Herald Tribune highlighted an important aspect of Russia's interest in developing cryogenic‐fuelled aircraft. The item read simply “The airport in Vladivostok, in far eastern Russia, closed down on Tuesday because it had run out of fuel.” The air routes to Vladivostok from Moscow and other major Russian cities are extremely long and all kerosene loaded at Vladivostok has to be transported there for the purpose. Fuel supply routes extend over thousands of kilometres whether they involve the limited road and rail links in that part of the world or marine tankers using equally‐long and challenging sea routes.

With the objective to assess potentially performant hybrid-electric architectures, this paper aims to present an aircraft performance level evaluation, in terms of range and payload, of the synergies between a hybrid-electric energy system configuration and a cryogenic fuel system.

An unmanned aerial vehicle (UAV) is modeled using an aircraft performance tool, modified to take into account the hybrid nature of the system. The fuel and thermal management systems are modeled looking to maximize the synergistic effects. The electrical system is defined in series with the thermal engine and the performance, in terms of weight and efficiency, are tracked as a function of the cooling temperature.

The results show up to a 46 per cent increase in range and up to 7 per cent gain on a payload with a reference hybrid-electric aircraft that uses conventional drop-in JP-8 fuel. The configuration that privileges a reduction in mass of the electric motors by taking advantage of the cryogenic coolant temperature shows the highest benefits. A sensitivity study is also presented showing the dependency on the modeling capabilities.

The synergistic combination of a cryogenic fuel and the additional heat sources of a hybrid-electric system with a tendency to higher electric component efficiency or reduced weight results in a considerable performance increase in terms of both range and payload.

The potential synergies between a cryogenic fuel and the electrical system of a hybrid-electric aircraft seem clear; however, at the present, no detailed performance evaluation at aircraft level that includes the fuel, thermal management and electric systems, has been published.

Special blanking covers are now being moulded by the Plastics Division of Hunting Aircraft Ltd. to protect the air intakes of the Hunting Jet Provost Trainer.

With the predicted rise in air traffic, a growing need exists to make the aviation industry more environmentally sustainable in the long-term future. Research has shown that the turbo-electric distributed propulsion system (TeDP) could be the next disruptive technology that has the potential to meet the ambitious environmental goals set for the N + 3 time frame. This however will require the use of superconductivity, application of high-temperature superconducting materials and cryogenic liquids. This paper provides a brief overview of the technology and further discusses the benefits, advantages and new opportunities that may arise from the application of the technology.

This paper provides a brief overview of the technology and further discusses the benefits, advantages and new opportunities that may arise from the application of the technology.

Implementation of superconducting technology is currently one of the greater challenges faced and hence this article also reviews some of the key considerations to enable utilisation of cryogenic fuels in the future.

This paper provides a viewpoint and reviews some of the work undertaken in the field. It also provides a perspective on some new possibilities and advantages from using TeDP with cryogenic fuels.

Mildew Test Kit To the naked eye, there is frequently very little difference between an exterior paint discoloured by mildew and one discoloured by dirt. However, a simple pocket‐size test kit has been developed which can distinguish in 95% of cases the difference between dirt and mildew. It is made by Durham Raw Materials Ltd., who manu‐facture Nuodex fungicides, and is available on request from them.

The purpose of this paper is to explore some of the challenges associated with the integration of an LH2-fuelled advanced hybrid-electric distributed propulsion system with the airframe. The airframe chosen as a case study is an ultra-high-capacity blended wing body configuration. It is designed to represent an A-380 class vehicle but in the 2025-2030 timeframe. The distributed propulsion system is a hybrid-electric concept that utilizes high-temperature superconducting technologies. The focus of the study is the application of LH2 as a fuel, with comment being given to kerosene and LCH4.

The study consists of a conceptual design developed through the preliminary design phase and part way into the detailed design phase.

The relationship between passenger capacity and fuel capacity is developed. Some remaining challenges are identified.

The study supports further conceptual design studies and more detailed system studies.

The study contributes to the development of more environmentally benign aviation technologies. The study may assist the development of solutions to the peak oil challenge.

The study explores the integration of a number of complex systems into an advanced airframe to an unusual depth of engineering detail.

Thermonuclear fusion is on the way, and beyond it the promise of limitless power derived from hydrogen in water and air. The challenge for the next few years will be to eke out our fossil fuels, and the most plentiful by far is coal. So how to reform a fuel that has long been considered the most environmentally unfriendly of them all?

WHEN talking about airbreathing engines it is now generally understood that they are either turbine engines when the maximum flight Mach number is subsonic or moderately supersonic, or ramjets when the Mach number is definitely high. When trying to meet the propulsion requirements from take‐off to a high enough speed the joint use of both engine types has to be considered. In such case most people would think of the ramjet as taking over the propulsion task from the turbine engine when reaching a certain value of the flight Mach number, or more precisely of the air stagnation temperature, above which the turbine engine is no longer able to operate. The most elementary view is that of presenting it as a limitation in the engine structure, with improvements calling for the use of better materials. Bringing thermo‐dynamics into the picture shows that increased air stagnation temperature results in a deterioration in the cycle efficiency of the turbine engine proper and this may result in the specific fuel consumption of the turbojet becoming higher than that of the ramjet. Such a performance limitation can be shifted to higher Mach numbers while using increased turbine intake temperatures. The consideration of the aerodynamics of the internal flow brings out another type of limitation due to the difficulty of keeping the operating line of the turbojet over the flight profile far enough from the surge limit though within the range of good compresser efficiency. Variable geometry in the compressor and turbine stators may produce some improvement in this respect.