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This paper is an overview of aero gas turbine engine starting systems and discusses the system design considerations and integration with other aircraft systems.

Review of a range of recent publications on the subject, aiming to provide an introduction to modern aero gas turbine engine starting systems.

Provides basic information on starter types and their limitations, and why some starter types are more favoured in modern installations. The effects of altitude and temperature are discussed which may not be initially considered as variables affecting aero start systems.

This paper provides further information on the starting systems of modern aero gas turbines and the considerations associated with integration and efficiency.

The purpose of this paper is to describe studies of accidental ignition of fuel‐air mixture. Studies were carried out in a laboratory that contains the naturally aspirated aircraft engine LYCOMNIG 320B1A IO type used in the EM‐11C Orka aircraft and the intake system to determine its resilience to the effects of accidental ignition and the occurrence of a backfire.

Tests were performed on a model under extreme conditions (with the intake system closed) and under conditions similar to normal operation using fuels of different combustion rates.

It was found that the positive pressure caused by such accidental ignition under normal operating conditions did not exceed 0.08 bar and did not pose any hazard of damaging the intake system of the IO‐320B1‐type LYCOMNIG naturally aspirated aircraft engine, as designed by the aircraft manufacturer.

The positive results of the tests of the EM11C Orka aircraft intake system's resistance to flashback and other positive test results for this aircraft have contributed to obtaining the EASA.A.115 Certificate and the EASA.21J.117 Certificate for the Design Unit, and the plane was presented at the AERO – Friedrichshafen 2011 Exhibition.

The paper described how, in the laboratory, simulated extreme operating conditions of the naturally aspirated aircraft engine intake system powered aircraft fuels with different burning speeds (aviation gasoline, hydrogen).

UNSATISFACTORY performance of an aircratt engine often leads to the ignition system being suspect without there being positive proof that this is where the trouble lies. A complete change of sparking plugs may have to be undertaken; alternatively other ignition components may have to be removed for substitution, bench test or examination. All this work may be necessary to locate the fault, and, in the end, it might even prove not to be in the ignition system at all.

The purpose of this paper is to investigate power performance, economy and hydrocarbons (HC)/carbon monoxide (CO) emissions of diesel fuel on a two-stoke direct injection (DI) spark ignition (SI) engine.

Experimental study was carried out on a two-stroke SI diesel-fuelled engine with air-assisted direct injection, whose power performance and HC/CO emissions characteristics under low-load conditions were analysed according to the effects of ignition energy, ignition advance angle (IAA), injection timing angle and excess-air-ratio.

The results indicate that, for the throttle position of 10%, a large IAA with adequate ignition energy effectively increases the power and decrease the HC emission. The optimal injection timing angle for power and fuel consumption is 60° crank angle (CA) before top dead centre (BTDC). Lean mixture improves the power performance with the HC/CO emissions greatly reduced. At the throttle position of 20%, the optimal IAA is 30°CA BTDC. The adequate ignition energy slightly improves the power output and greatly decreases HC/CO emissions. Advancing the injection timing improves the power and fuel consumption but should not exceed the exhaust port closing timing in case of scavenging losses. Burning stoichiometric mixture achieves maximum power, whereas burning lean mixture obviously reduces the fuel consumption and the HC/CO emissions.

Gasoline has a low flash point, a high-saturated vapour pressure and relatively high volatility, and it is a potential hazard near a naked flame at room temperature, which can create significant security risks for its storage, transport and use. The authors adopt a low volatility diesel fuel for all vehicles and equipment to minimise the number of different devices using various fuels and improve the potential military application safety.

Under low-load conditions, the two stroke port-injected SI engine performance of burning heavy fuels including diesel or kerosene was shown to be worse than those of gasoline. The authors have tried to use the DI method to improve the performance of the diesel-fuelled engine in starting and low-load conditions.

Aeronautical research scientists of the National Advisory Committee for Aeronautics have in the last six years indexed 7,070 non‐security classified NACA research reports under 458 different subject classification headings for a total of 18,619 subject entries. They further face the task of subject classifying over 400 similar research reports per year, plus the large number of security classified reports issued annually.

Global value changes continued to expand until the late 2000s. On the other hand, regional value chains have formed around major regional hubs due to the expansion of domestic demand in emerging economies, such as China, and strengthened trade protectionism since the global financial crisis. Such changes lead to the reorganisation of value chains, focusing on domestic markets (reshoring) or neighbouring countries (nearshoring). In particular, the importance of supply chain risk management has been highlighted following disruptions to the supply network due to the COVID-19 outbreak in December 2019. In this regard, major countries such as the USA and the EU are rapidly shifting to regional value chains for stable and sustainable production, rather than primarily aiming for production efficiency targeted at reducing costs. Industries in particular are more exposed to such supply chain risks under the existing structure and it now has become extremely important for businesses to take reaction to such risks. This is especially important for major industries in a country such as automobile or semiconductor manufacturing industries in South Korea. The aim of this study, therefore, is to establish the basis for the simultaneous growth of ports and linked industries by examining the existing structure of the global value chain for the automotive industry, which has a strong presence in South Korea’s domestic economy. In this regard, this research carries out a supply chain analysis focusing on the imports and exports of automotive parts. It also analyses the current structural risks and suggests risk management measures to secure a stable supply chain.

AT the end of the war in 1945, aircraft systems could still be classified as ‘auxiliary’ and ‘ancillary’—those which were essential for flight and those which were installed for reasons of safety, crew or passenger comfort and operational efficiency. Thus auxiliary systems generally included only the fuel system and ignition system, and many aircraft, particularly military, were flown into repair depots with one or more of the ancillary systems inoperative.

SOME literature on the subject of jet‐propulsion power units for aircraft is now available. These have, however, in the main, been primarily concerned with the description and performance of these units. Little, if anything, of the serviceing and serviceing requirements of the gas turbine has been written.

The Rolls‐Royce Trent 800, powerplant of the new Boeing 777 twinjet airliner, successfully completed a 150‐hour block endurance test, taking it closer to on‐schedule certification in January.

The Westland Lynx helicopter is a particularly fine example of the use of advanced fan technology in modern aircraft applications. The firm of Airscrew Howden have come a long way from their original manufacture of the wooden ‘prop’ but they still continue to play a very essential part in all types of aircraft flying today; this takes the form of sophisticated fan designs to cover a wide variety of special air‐movement requirements that can arise in this sector.