Lesson 3 - The Aviation Industry Today (S1 2023-2024) PDF

Click to edit Lesson Master 3title style -The Aviation Industry Today By Ir WC Cheung  CAR - Click to edit Master title style Objectives The economic and soc...

Click to edit Lesson Master 3title style -The Aviation Industry Today By Ir WC Cheung  CAR - Click to edit Master title style Objectives The economic and social benefits of air transport The impact of Covid-19 to the aviation industry The impact of aviation on the environment Strategies to minimise the environmental impact Slide 2  CAR - Click to edit Master title style The economic and social benefits of air transport Slide 3  CAR - The Clickeconomic and social to edit Master titlebenefits style of air transport The airline industry globally The airline industry provides a service to most countries in the world. It has an integral role in the global economy. The airline industry is a major economic force, in both its own operations and the impact on related industries such as aircraft manufacturing, tourism etc. The air transport industry consists of a global network of commercial aircraft operators, airports, air navigation service providers and manufacturers of aircraft and their components. It is responsible for connecting the global economy, providing millions of jobs and making the modern, internationally connected quality of life possible. ATAG - “Beyond the Borders” https://www.atag.org/ Slide 4  CAR - The economic and social benefits of air transport Click to edit Master title style The air transport industry has seen rapid growth, which has been driven by a number of factors, including: Rising GDP – disposable income, and living standards – increasing the demand for travel for both business and leisure purposes. Reduced air travel costs – improvements in airline efficiency and increased competition have reduced world airfares Globalisation – the average distance travelled tends to increase as people take long- haul holidays and do business in countries which now have more favourable political and social environments. Deregulation – The US domestic air market in the 1970s, followed by the European Union in the 1980s (completed in the 1990s), with other regions following. Slide 5  CAR - The Clickeconomic and social to edit Master titlebenefits style of air transport Technological innovations enabled this growth The global airline industry has seen The introduction of jet aircraft for commercial use in the 1950s, The development of wide-body “jumbo jets” in the 1970s. World airlines were heavily regulated during these times, creating an environment in which technological advances and government policy took precedence over profitability and competition. Slide 6  CAR - The Clickeconomic and social to edit Master titlebenefits style of air transport Airline deregulation starting around 1978 Many new airlines were formed, and cost efficiency, operating profitability and competitive behavior have become the dominant issues facing airline management. Airline deregulation started in the USA affecting both domestic and international air travel as countries followed this trend. This led to the continuing evolution of a highly competitive international airline industry. Slide 7  CAR - The Clickeconomic and social to edit Master titlebenefits style of air transport Positive impacts of aviation industry: It is a major global employer and an enabler for economic growth A substantial investor in infrastructure such as runways, airport terminals, railways and roads between airport and downtown, creating many jobs Provides significant social benefits such as tourism and trade, which generates economic growth, improving living standards and alleviating poverty and increasing revenues from taxes Increased cross-border travel leads to closer relationships developing between countries This all facilitates the development of social and economic networks that will have long lasting effects Slide 8  CAR - The Clickeconomic and social to edit Master titlebenefits style of air transport In 2019 (Pre-Covid-19) The airline industry consists of over 1,400 commercial airlines operating more than 33,000 commercial aircraft (Turboprops + Jet engine aircraft) Providing services to 4.5 billion passengers to 3,700 airports 47 million scheduled commercial flights (ATAG, Sep 2020). Total Revenue Passenger Kilometres (RPK) (revenue passengers x distance flown) generated was 8.68 trillion Air transport also carries about 35% of world trade (high value and/or time sensitive cargoes) by value (USD6.5 trillion) and less than 1% by volume Slide 9  CAR - The Clickeconomic and social to edit Master titlebenefits style of air transport Source: The Air Transport Action Group (ATAG) 2004 https://www.atag.org Slide 10  CAR - The Clickeconomic and social to edit Master titlebenefits style of air transport Aviation’s global employment and GDP impact Pre-Covid-19 ATAG Sep 2020 Aviation jobs worldwide: 87.7 million Global economic impact (including direct, indirect, induced and tourism catalytic): USD3.5 Trillion Global GDP supported by Aviation: 4.1% (3.5 trillion -In country terms, it would be 17th in the world, similar to Holland or Indonesia) 11.3 million jobs directly employed in aviation [4.1% 93.5 trillion) of Global GDP ] Slide 11  CAR - The Clickeconomic and social to edit Master titlebenefits style of air transport Major Areas of ‘Direct’ jobs Major Sub-Areas No. of jobs (million) Airlines Executives 3.6 Flight and cabin crews Ground services Check-in Training Maintenance/Engineering Airport Operators Airport Operations 0.648 Planning Engineering Security Civil Aerospace Engineers and designers of civil aircraft 1.3 Engineers and designers of civil engines Engineers and designers of aircraft/engine components Air Navigation Service Providers Executives 0.237 Air Traffic Controllers Engineers Other on-site airport Customs and Immigration 5.5 Freight forwarder Catering Retail Car Rental Total 11.3 Slide 12  CAR - The Clickeconomic and social to edit Master titlebenefits style of air transport DIRECT AVIATION JOBS – TOTAL 11.3M (Source: ATAG 2020) – Pre COVID 19 3.6m (31.9%) Airlines 5.5m (48.7%) Other on-site airport 1.3m(11.5%) 0.65m (5.7%) 0.24m (2.1%) Airport Operators Civil Aerospace Air Navigation Service Providers Slide 13  CAR - Click to edit Master title style Impact of Covid-19 to the aviation industry Slide 14  CAR - Impact Click toofedit Covid-19 to title Master the aviation style industry The aviation industry has had many crises since World War 1 These have led to a drop in air passenger traffic with a quick recovery However the Covid-19 crisis is the exception 1914 2020 Slide 15  CAR - Impact Click to of editCovid-19 Master to titlethe styleaviation industry Impact of Covid-19 on jobs and GDP: (Source ATAG 2020) Pre-Covid-19 (2018) Post-Covid-19 (early 2021) Change (%) Jobs (in millions) Aviation Direct 11.3 6.5 -42.5 Indirect 18.1 9.7 -46.4 Induced 13.5 7 -48.1 Tourism Catalytic 44.8 18.4 -58.9 Total 87.7 41.6 -52.6 GDP (in billions) Aviation Direct 961.3 491 -48.9 Indirect 816.4 439 -46.2 Induced 692.8 365 -47.3 Tourism Catalytic 1000 403 -59.7 Total 3470.5 1698 -51.1 Slide 16  CAR - Click to edit Master title style Impact of aviation on environment Slide 17  CAR - Environmental Impactstitle style Click to edit Master Environmental Impact may be: Localized to the airports People living under flight paths People working close to these areas. The impact may be greater, ultimately affecting the atmosphere resulting in climate change The impact could be: Noise emissions Green house gas (GHG) emissions (Carbon Dioxide - CO2, Nitrogen Oxides - NOX, Methane - CH4, Ozone - O3 etc.) Slide 18  CAR - Environmental Impactstitle style Click to edit Master Environmental Impacts: (Source: ATAG 2020) Carbon Emissions: In 2019: 363 billion litres (= 290 million tonnes) of jet fuel were used by commercial operators. This is equivalent to 8% of global liquid fuel use A total of 914 million tonnes of carbon dioxide was emitted, which is 2.1% of the global human CO2 emissions of 43.1 billion tonnes Slide 19  CAR - Environmental Impactstitle style Click to edit Master Noise: Aviation has environmental impacts experienced by local residents in the vicinity of airports and under flight paths. Noise has been the focus of concern over the last 40 years of growth in aviation More recently air pollution and the health effects from aircraft and other forms of transport are causing increasing concern. Slide 20  CAR - Environmental Impactstitle style Click to edit Master Noise Pollution: Noise damages health, wildlife, and the learning ability of schoolchildren. It costs a great deal of money to mitigate the effects of noise pollution. Aircraft noise is a serious concern around all airports and under flight paths despite the adoption of quieter aircraft and engine technology. Aircraft noise is a controversial matter and it needs to be addressed. Slide 21  CAR - Environmental Impactstitle style Click to edit Master Noise Pollution: (cont’d) Noise is measured on the Decibel Scale usually expressed as dB. (Effective perceived noise level EPNdB is used in ICAO Annex 16) The scale is used by public health and environmental health officials to set limits or make recommendations about limits that should not be exceeded. A limit of 55dB is regarded as one which should not be exceeded to protect undisturbed sleep and sound levels above 70dB make normal speech communication impossible Slide 22  CAR - Environmental Impactstitle style Click to edit Master Ground level air emissions: Research (Natural Resources Defense Council, 1996) shows that air pollution from cars and industry has declined with time while aircraft continue to emit more ground level ozone precursors (Volatile Organic Compounds or VOCs and nitrogen oxides or NOX) with each passing year. Airports in the US are on the top four largest emitters of NOX and VOCs (depending on location), together with power plants, the chemical industry and oil refineries. Slide 23  CAR - Environmental Impactstitle style Click to edit Master Airports generate traffic: Bus, train and taxi journeys stations cause significant amounts of pollution from their exhaust emissions Freight distribution centres Equipment to service the aircraft, fixed and mobile electric generating equipment to supply aircraft maintenance facilities for engines and aircraft There are fuel depots with storage tanks, fuel lines and refuelling facilities all contributing evaporative emissions of VOCs to atmosphere Slide 24  CAR - Environmental Impactstitle style Click to edit Master The effects on human health are: Carbon Monoxide (CO) Very high levels cause death; High levels cause headaches, drowsiness, nausea, affects reflexes. Low levels affects concentration, the nervous system causing exercise-related heart pain in people with coronary heart disease Nitrogen Oxides (NOx) Impair respiratory cell function, damage blood capillaries and the immune system and may aggravate asthma, in children this may result in coughs, colds, phlegm (痰), shortness of breath, wheezing (慢性氣喘) and respiratory diseases. Slide 25  CAR - Environmental Impactstitle style Click to edit Master The effects on human health are: Ozone Ozone at ground level reduces lung function in people with asthma and indeed heathy people. Increasing susceptibility to infection and to allergens such as pollens and house dust mites (塵蟎). Causing coughs, eye, nose and throat irritation, headaches, nausea, chest pain and loss of lung efficiency increasing the likelihood of asthma attacks(哮喘發作). Particulate matter (PM) Are strongly associated with coughs, colds. Sinusitis (鼻竇炎), shortness of breath, chest pain, asthma, bronchitis, loss of lung efficiency etc. Long term exposure increases the risk of death from heart and lung diseases. PM may carry carcinogens (致癌物) such as polycyclic aromatic hydrocarbons (多環芳烴-PAHs), increasing the risk of cancer. Slide 26  CAR - Environmental Impacts Click to edit Master title style The hazardous effects of these pollutants - Summary Volatile Organic Compounds (VOC): These include many different chemicals many of which are hydrocarbons (HC). They may cause skin irritation and breathing difficulties; long term exposure may impair lung function. Carcinogens. Benzene can cause leukaemia (白血病). Those most at risk are people exposed to benzene at work or who live or work in the vicinity of petrol filling stations or general vehicle activity. Sulphur Dioxide (SO2) irritates the lungs and is associated with chronic bronchitis. People with asthma are vulnerable, a few minute's exposure may trigger an attack. The most serious effect is when SO2 is absorbed by particulate matter and then inhaled deep into the lungs. At high doses this can release sulphuric acid by reaction with moisture in the lungs. This can result in death and serious illness, it is thought to have been the main cause of the 4000 deaths during the notorious 1952 London smog. Slide 27  CAR - Environmental Impactstitle style Click to edit Master Larger Scale Impacts Flying and climate change The atmospheric impact of pollution from aviation with an emphasis on greenhouse gases (GHG) and climate change. NOx and CO2 are the most significant pollutants due to their impact on the atmosphere, other gases have some impact too. Slide 28  CAR - Environmental Impactstitle style Click to edit Master Impacts of Emissions Aircraft emit exhaust gas pollutants directly in the upper troposphere (對流層) and lower stratosphere (平流層 下層). These emissions interact in the sensitive parts of the atmosphere and are responsible for changes in ozone and methane concentration thus forming contrails The most important aviation - derived factors influencing the atmosphere are: Carbon dioxide Ozone (enhanced by NOx levels) Methane (CH4)(甲烷) Water vapour Contrails (凝結尾跡) Sulphates Soot aerosols (煙塵氣溶膠) Contrails Slide 29  CAR - Environmental Impactstitle style Click to edit Master Carbon dioxide, CO2 CO2 emissions from aviation have the same impact on the climate as those from other sources These emissions accumulate in the atmosphere and have a direct radiative forcing effect, irrespective of the site and height of emission. Aviation today is the source of about 13% of transport-derived CO2 emissions Slide 30  CAR - Environmental Impactstitle style Click to edit Master Direct radiative forcing effect Radiative forcing is the difference between solar radiation (sunlight) absorbed by the Earth and energy radiated back to space. Positive radiative forcing means Earth receives more incoming energy from sunlight than it radiates to space. This net gain of energy will cause warming Slide 31  CAR - Environmental Impactstitle style Click to edit Master Nitrogen oxides (NOx) In contrast to CO2,NOx emissions from aircraft have a different impact depending on the location of the emission. In the Northern hemisphere NOx emissions from aircraft are increasing ozone concentrations at cruise level in the upper troposphere and lower stratosphere. Calculations predict increases in summer in the principal traffic areas of about 6%. Ozone is a very potent greenhouse gas. Slide 32  CAR - Environmental Impacts Click to edit Contrails (short Master TRAILs): for CONdensation title style When jet aircraft burn fuel at altitudes of 10-12 km water vapour produced forms in the atmosphere, temperatures are approximately -50oC to -60oC. This water vapour freezes into tiny ice particles (sometimes in association with particulates) which form the familiar trails, known as "contrails“, behind aircraft when viewed from the ground. Contrails can be long lasting depending on weather conditions Contrails and spread to a width of tens of kilometres. In busy airspace, (e.g. Europe and the North Atlantic) contrails can cover 5% of the sky area annually. This busy airspace will be subject to a greater greenhouse effect Slide 33  CAR - Click to edit Master title style Strategies to Minimise Environmental Impact Slide 34  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Aviation technologies Engine technology (see later slides for description) Open rotor engine designs Geared Turbofan engines Improved aircraft aerodynamics / reduced aerodynamic drag Flying wing and blended wing-body configurations Use of lightweight materials for aircraft construction Operational and Air Traffic Management System (ATMS) Continuous descent approach (CDA) Improvement to current ATMS Operational changes to reduce fuel consumption Noise reduction measures Slide 35  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Alternative fuels Biodiesel Liquid / gaseous hydrogen All Electric Aircraft Accelerating fleet turnover Recommendations (SARPs) - ICAO Regulations - Government Agencies Slide 36  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Trends in Fuel Efficiency MJ/pkm= Megajoule / (1) Significant improvement from the 1960’s passenger kilometre (2) Long range and short range improvements converge from the mid 1970’s Short range aircraft trend Long range aircraft trend (1) The range of points reflects different configurations (2) Connected dots show estimated trends for short-and long-range aircrafts. Source: IEA/OECD (2009) Transport, Energy and CO2: Moving toward sustainability. Paris: International Energy Agency. Slide 37  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Technologies: Improving aircraft fuel efficiency can be achieved with engine efficiencies, drag reduction and reducing the weight. A lot of these efficiencies are interdependent. For example, the Boeing quotes B787 design advantages overview 20% fuel efficiency improvement 30% reduction in maintenance costs 15% lower operating costs Typically of the 20%, 8% comes from engines and 12% from aerodynamic improvements, the use of lighter composite materials, and advanced control systems. A significant reduction is required to make the aircraft attractive to buy, likely a 10% to 15% in operating costs, including fuel costs). Slide 38  CAR - Strategies Click to Minimise to edit Environmental Master title style Impact Engine Technology Improving propulsion efficiency Increasing thermal efficiency Reducing noise levels Reducing NOx emissions Stringent safety standards, noise and pollution reductions often implies a trade-off with fuel efficiency. Improving thermal efficiency focuses on higher temperatures and pressures, with advances in compressor blade aerodynamics and new materials make important contributions. However higher temperatures and pressures increase NOx emissions. Developments - water injection, intercooling chilled air coolers. Slide 39  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Engine Material (blade materials - higher temp) Improvement: Turbine Blade=USD20K each 92 pieces = USD1.2m per set! This is the cost of turbine blades per engine! Slide 40  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Technology – improved cooling and thermodynamic coating Single Pass Multi Pass Thermal Barrier Coating (ceramics) Slide 41  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Engine Materials Multiple metals and composites are used Slide 42  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Turbofan engine vs Jet Engine: INTAKE COMBUSTION EXHAUST Combustion Turbine Inlet chambers section Turbofan runs quieter Jet engine generates more noise Slide 43  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Future development? or…. UnDucted Fan (UDF) / Propfan / Open rotor engine External blades in two stages that rotate in opposite directions Advantage: Potential fuel efficiency improvement and CO2 emissions reduction of up to 30% compared to current aircraft Disadvantage: Noise, there is no fan case to muffle the noise of the rotating blades. The fan case (in the case of fan engine) minimizes the noise levels Work is required to comply with noise regulations Slide 44  CAR - Strategies to Minimise Environmental Impact Click to edit Master title style ……..Back to the future The Boeing 7J7-An UnDucted Fan (UDF) prop-fan engine Proposed in the 1980s A 150 seat aircraft planned to be a successor to the Boeing 727 Initially planned to enter service in 1992 An early example of fuel efficient design with two rows of contra- rotating blades Dropped due to price drop of oil in the 1980s. Slide 45  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Open rotor engine / unducted fan (UDF) or propfan https://www.youtube.com/watch?v=APzO7OVGakw Slide 46  FTO - Strategies to Minimise Click to edit Environmental Master title style Impact The future reimaged… In June 2021, GE and SAFRAN announced an extension of their CFM joint venture to 2050 and a program called RISE. Revolutionary Innovation for Sustainable Engines (RISE), develops the previous work CFM, plans to bring this engine to the market consuming a minimum of 20% less fuel and a 20% reduction of CO2 emissions compared to existing engines. This engine has a single fan (rotor) plus stator (variable vanes) - the 1980’s technology had two contrarotating fans Source and © CFM Slide 47  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact A Fan engine (Turbofan) and Profan engine: Ducted Fan Unducted Fan Slide 48  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Engine Technology: Geared Turbofan (GTF) The geared turbofan is a turbofan engine, with a gearbox between the fan and the low pressure shaft to spin each at optimum rotational speeds Conventionally the "low-pressure" (LP) shaft connects the fan, the low-pressure compressor and the low-pressure turbine A second concentric shaft connects the high-pressure compressor and high-pressure turbine. In this configuration, the maximum tip speed for the larger radius fan limits the rotational speed for the LP shaft and thus the LP compressor and turbine. In a geared turbofan, a reduction gearbox between the fan and the LP shaft allows the latter to run at a higher rotational speed thus enabling fewer stages to be used in both the LP turbine and the LP compressor, increasing efficiency and reducing weight. The lower fan speed allows higher bypass ratios, i.e. a bigger fan diameter , leading to reduced fuel consumption and much reduced noise. Slide 49  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact History TURBOJET – Intake air went to the compressor, then to the combustion chamber, mixed with fuel ignited driving a turbine and generating thrust from the exhaust gases TURBOFAN – First stage fan diverts a proportion of the airflow around the core, this air is at a lower speed and generates thrust more efficiently GEARED TURBOFAN – A gearbox drives a bigger fan at a lower speed this enables a larger volume of air to be diverted around the core Slide 50  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Engine Technology history Slide 51  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Engine Technology: Geared Turbofan (GTF) For a given fan diameter, D, and rotational speed, N (in revolution/minute, N RPM), the linear velocity at the fan tip V, = (2π ∗ D/2 ∗ ) metres/second. 60 If either D or N is too large, V may reach the speed of sound, shock waves will be formed at the tip, resulting in losses, e.g. pressure, efficiencies etc. Hence the low pressure turbine, which is directly connected to the fan, cannot rotate at its optimum speed in order to avoid shock wave formation at the fan tip The GTF by design removes this limitation Slide 52  CAR - Strategies Click to Minimise to edit Environmental Master title style Impact Engine Technology: PW1100G - A320neo Geared Turbofan (GTF) Upper Half - Geared Turbofan Fuel consumption and CO2 emissions are reduced by 16%, and the noise footprint by 75%. Fewer compressor and turbine stages are needed, the engines are lighter, and maintenance costs reduced, because fewer com- ponents are exposed to the hot gases. It will be possible to achieve even lower fan pressure ratios in the future, this should increase the bypass ratio - from 12:1 towards 20:1 by 2035 Engineers are working to further improve the core engine’s ther- mal efficiency by increasing the pressure and temperature ratios. These are in development for more efficiencies Lower Half - Conventional Turbofan Slide 53  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Engine Technology: PW1100G Geared Turbofan (GTF) The gearbox allows the Low Pressure Turbine (LPT) to run at a different (higher) speed which is optimum for improved fuel efficiency This is not possible for a turbofan engine as the fan and LPT are connected directly Slide 54  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact PW1100G Geared Turbofan (GTF) https://www.youtube.com/watch?v=3z5ERdmTbxs Slide 55  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Noise Suppression: Sources of Engine Noise: Measured in Decibels (dB) Mainly from the compressor, turbine and exhaust gases The compressor and turbine noises are from the reaction and interaction of the rotating and stationary blade stages. Defined as two distinct types, discrete tone and background Discrete tone comes from the regular passage of the rotating blades through the wakes from the preceding stators. In high by-pass ratio engine, same discrete tone is also produced by the LP fan blade wakes (turbulence) passing over the stators downstream but of lower intensity due to lower velocities Slide 56  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Noise Suppression: Sources of Engine Noise: The reaction and interaction of the wakes of rotating and stationary blade Turbine Blades Slide 57  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Noise Suppression: Sources of Engine Noise: Background noise is produced from the reaction of each blade to the passage of air over the surface, even if the air is not turbulent Increase of turbulence level only increases the intensity of the background noise. Slide 58  CAR - Strategies to Minimise Environmental Click to edit Master title style Impact Noise Suppression: Exhaust noise comes from the mixing of the high speed exhaust with the surrounding ambient air outside the exhaust. The higher the mixing rate, or the smaller the difference between the speed of the exhaust gases and the surrounding air, the lower the noise level Exhaust noise is produced by the shear of high velocity gases through still air If the velocity of the gas is slowed and the mixing area is increased, the exhaust noise level may be reduced to a level where noise suppression may no longer be necessary This is achieved by increasing the contact area of the atmosphere with the gas stream using an exhaust nozzle incorporating a corrugated or lobe-type noise suppressor. Slide 59  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Noise Suppression: a) Corrugated-Perimeter-Type b) Multiple Tube-Type They are used to break up the main jet exhaust into a number of smaller exhausts The shape of the noise suppressors increases the total perimeter of the nozzle area and reduces the size of the eddies created (turbulence) as the gases are discharged into the atmosphere. Slide 60  CAR - Click to edittoMaster Strategies Minimise titleEnvironmental style Impact Noise Suppression: Discrete tone noise (between stators and rotors): Noise generated by the wakes of the stators interacting with rotors (rotating blades) will create high-frequency pressure fluctuations These may be dampened or absorbed by appropriate acoustic materials. These are made of perforated honeycomb panels called gas generator fairings These fairings absorb Compressor and Turbine Noise Slide 61  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Noise Absorbing Material Locations: surrounding the core engine Slide 62  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Noise Suppression: The velocity of the exhaust gas in a high-bypass ratio turbofan engine is low because most of the gas energy is used to drive the fan The velocity of the fan exhaust also travels at low velocity so high bypass ratio engines are not normally fitted with noise suppressors The RB211-524G-T and CFM56-5C4 are exceptions where a corrugated type noise suppressor is fitted. Slide 63  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Noise Suppression: RB211-524G-T (on the B747-400 aircraft) Corrugated Perimeter Type Noise Suppressor Slide 64  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Noise Suppression: CFM56-5C4 Engine fitted to an Airbus A340-300 Aircraft Exhaust mixer Slide 65  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Noise Suppression: B747-8 – Chevrons on the trailing edge of the outer panels of the translating sleeve decrease noise Slide 66  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Technology: Improving the aerodynamics hence reducing drag (mainly high lift / drag ratio) Fuel consumption varies roughly inversely with the lift-to-drag ratio at cruise speeds. Increasing this ratio (L/D) is potentially an effective means to reduce fuel consumption. Lift / drag ratios can be increased with wingspan extensions ( increasing the Aspect Ratio) Winglets improve the lift / drag ratio. An of 4% to 7% may yield fuel savings of 1% to 2% Small vortex generators (and strake to engine nacelles) on the wing upper surface may increase lift / drag ratio and improve fuel consumption by 1 to 2% Having a smooth and continuous surface on the engine nacelle, wing and fuselage will minimize drag and fuel consumption Noise reduction, from airflow over the overpressure relief outlets on the lower wing surface of the A320 aircraft Slide 67  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Technology: Examples, source Boeing and Airbus Vortex generators on wing surface Wing Span Strake Slide 68  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Technology: A320 vortex generators These are mounted in front of the cavities to prevent the generation of tones, giving a 4dB noise reduction at distances between 10 and 17 kms from the runway. These are a standard on new A320 aircraft and can also be retrofitted. These vortex generators help to reduce noise related airport charges. https://www.lufthansagroup.com/en/responsibility/climate-environment/active-noise-abatement.html Slide 69  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Jet blast deflector for engine ground run: A jet blast deflector (JBD) or blast fence is a safety device that redirects the high energy exhaust from a jet engine to prevent damage and injury. At maintenance areas, jet blast deflectors are combined with sound deadening walls forming an enclosure within which jet engines can be safely tested at high power while maintaining noise levels to an acceptable level. Slide 70  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Noise Suppression: Engine ground run enclosure https://www.youtube.com/watch?v=vJBXzOLkKiM Slide 71  CAR - Strategies to Minimise Environmental Click to edit Master title style Impact Design Wing design on long-haul aircraft is optimized to minimise fuel burn at cruising speeds. This entails a trade-off between wingspan and wing weight. The fuel efficiency benefits of increasing current wing-spans are offset by the fuel needed to carry the increased weight of the wing. Design cruise speeds could be reduced to allow a reduced sweep of the wing. Alternately, advanced composite wing skins could be used to reduce weight and allow an increased wingspan. Initially the B777-200/300 were designed with winglets but were rejected by airlines because the fuel saved was too insignificant for the routes flown (additional weight of the winglets induced additional fuel burn), i.e. one needs to conduct a cost/benefit analysis as all winglets will incur a drag and weight penalty. Slide 72  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Wing tip design B777-200LR and -300ER have raked wing tips with a 6.5 feet tapered wing-tip extension, improving Takeoff performance Fuel efficiency Climb performance. Improved climb performance also means less noise in the departure airport area The B777 tapered wing tip -200LR and -300ER Slide 73  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Blended wing body design concept This design differs radically from current civil aircraft This has supercritical wings, but the fuselage is a lifting body, aerodynamically shaped to achieve enhanced low speed and cruise performance without the need for conventional flaps and a tail. Slide 74  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Blended wing body design Yaw is controlled by the so called split/clamshell ailerons For example, the B2 Spirit Aircraft The split ailerons/elevons (or clamshell ailerons) on the trailing section are designed to split into two surfaces on the top and bottom opening to the aft of the aircraft. By actuating them differentially, more drag is create on one side, causing a directional change. The use of differential thrust may have a small effect as the engines are mounted close to the centreline of the fuselage It is necessary to have an advanced (Active Control) control system (Fly By Wire) providing control of each of the control surfaces Slide 75  CAR - Strategies to Minimise Environmental Impact Click to edit Master title style B2 Spirit Aircraft Slide 76  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact NASA / Boeing research Blended Wing Body aircraft The X-48B completed 92 flights between 2007 and 2010 at NASA Dryden Boeing and NASA’s remotely piloted X-48C aircraft flew on August 7 2012 The X-48C model was modified to evaluate the low-speed stability and control of a low-noise version of a future Hybrid Wing Body (HWB) aircraft design. The HWB design stems from concept studies being conducted by NASA's Environmentally Responsible Aviation project of future potential aircraft designs. https://www.nasa.gov/topics/aeronautics/features/x48c_transformer.html NASA future aircraft evolution UAV technology (24m 33s) - https://www.youtube.com/watch?v=JdO2fvJr3VI Slide 77  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Boeing X-48C Flight demo Boeing X-48C demonstrator concept (2m 04s) - https://www.youtube.com/watch?v=28blrKKg0Uo Slide 78  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Airbus Maveric A blended wing body demonstrator Possible fuel savings of up to 20% Quiet aircraft by design First flight in June 2019 Slide 79  CAR - Strategies to Minimise Environmental Impact Click to edit Master title style Materials: Aircraft weight reduction using new materials and composites can also significantly improve fuel efficiency. Much of the current effort of aircraft manufacturers and component suppliers to reduce fuel consumption and GHG emissions is concentrated in this area. Carbon-fibre Reinforced Plastic (CFRP) is stronger and stiffer than metals such as aluminium, titanium or steel, but its relative weight per volume is half that of aluminium and one-fifth of that of steel. In addition, CFRP is highly corrosion resistant and has better fatigue resistance when produced under ideal manufacturing conditions. A big challenges is to ensure quality control in manufacture. Slide 80  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact The use of CFRP in aircraft construction About 50% of the fuselage weight of the Boeing 787 and A350 is made up of CFRP, this contributes approximately one-third of the aircraft’s 20% fuel efficiency advantage over comparable existing aircraft. The use of this material in wings, wing boxes and fuselages will increase as the technology matures. Complete replacement of aluminum by CFRP could provide a 10% weight reduction in medium-range aircraft, and 15% in long-range aircraft. Weight reduction in engines can be achieved using composite materials with high-temperature tolerances. This not only reduces weight but may also lead to higher operating temperatures with greater combustion efficiency, both of which lead to reduced fuel consumption. Slide 81  CAR - Strategies to Minimise Environmental Click to edit Master title style Impact Slide 82  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Operational and ATMS improvements: (More details on ATMS in Week 8,9 and 10) Air Traffic Management System (ATMS) aircraft movements on the ground and in flight can have an important impact on fuel use. All phases of flight, start-up, taxi, take-off, cruise, approach and landing taxiing after arrival, operations must balance traffic congestion (aircraft is held up on the ramp or a given altitude waiting for ATC clearance for takeoff or landing, respectively), safety and fuel burn issues. Current operational practices are not always optimal from a fuel burn perspective. New technologies, as well as changes in operational procedures, could play a role in reducing fuel burn. Slide 83  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Operational and ATMS improvements: (More details on ATMS in Week 8,9 and 10) Different Flight Phases: Slide 84  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Air Traffic Management Systems (ATMS) The current air traffic management (ATM) system pays little regard to fuel use. It has been estimated that current ATM systems and practices in Europe mean that, while maintaining essential safety margins, the fuel burn is 7% to 12% higher than necessary. A number of current practices reduce the fuel efficiency of ATM and operations. Longer routes are flown due to: Airspace fragmentation. Traffic management at airports is often on a first-come, first-served basis, while aircraft have designated slot times on the runway for take-off. The ATM systems are not optimised to minimise fuel burn, this means that there are additional CO2 and noise emissions as aircraft queue to take off, than the theoretical minimum Slide 85  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Operational strategies Continuous descent approach (CDA): The operation of an aircraft on final approach influences the fuel consumption and noise. Aircraft are cleared to descend to successively lower altitudes with periods of level flight between descents, red flight path This flight path is not efficient and will result in a higher noise and fuel consumption Flying a Continuous Descent Approach (CDA) from cruise altitude to fly the correct glide slope for landing, green flight path Slide 86  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Modern ATM and aircraft systems make the CDA viable for most approaches Airspace constraints or safety issues may limit use in some circumstances. CDA is applied at most airports Analysis has shown that CDA could typically save between 5% and 10% of the fuel used in a Boeing 767 or 757 aircraft from the top of descent (about 300 kms) to landing. Typical fuel burn in the descent from cruising altitude is between 300kgs and 500kgs, so this reduction applied to all airplane in a fleet will add up to savings of millions of dollars every year Slide 87  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact All Electric Aircraft (AEA) The Airbus/Rolls-Royce/Siemens E-Fan X was a hybrid research / demonstrator A 2MW (2,700 hp) electric motor to replace one of the 4 engines in the BAe146 flying testbed. Launching and testing the possibilities – and limitations – of a serial hybrid- electric propulsion system Gaining insights to develop a focused roadmap on how to progress on our ambitious decarbonisation commitments, laying a foundation for the future adoption and regulatory acceptance of alternative-propulsion commercial aircraft. Airbus and Rolls-Royce made the joint decision to bring the E-Fan X demonstrator to an end in April 2020. Slide 88  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Accelerating fleet turnover: Aircraft have a service life of typically 30 years, buying more fuel efficient planes can provide net economic benefits after a few years of operation, this can be an expensive option and the benefits will tend to decline as planes are brought out of service increasingly early. Some airlines, e.g. Singapore Airlines, tend to retire their aircraft early so as to reduce operational (including maintenance costs) and fuel costs. There are many airlines which continue to operate older generation aircraft which are not fuel efficient (hence with high carbon emissions) but generating a lot of noises. The related National Aviation Authority (NAA), here HKCAD, should tighten up their requirement from ICAO Annex Chapter 3 to Chapter 4. This will ensure older aircraft will not fly into Hong Kong. Slide 89  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact ICAO and/or Government Agencies: ICAO can set more aggressive targets for carbon emissions reduction and noise by encouraging more innovative technology to be adopted Government agencies should provide tax incentives for airlines which operate young fleet and/or perform better than the pre-agreed carbon and noise reduction targets Local aviation authorities should disallow ageing fleet to operate into their regions/countries unless the aircraft concerned meet at least a certain standard, e.g. Chapter 4 of Annex 16 Part 1 Slide 90  CAR - Strategies to Minimise Click to edit Environmental Master title style Impact Comparison of fuel consumption reduction potential This shows the potential improvements possible in the areas noted Airframe and engine technologies will require new aircraft / engines to benefit ATM and operations can be implemented subject to the capability of the various systems Slide 91 Click to edit Master title style Questions? Click to edit Master title style Thank You