Royal Aeronautical Society annual conference

Citation

Ford, T. (2006), "Royal Aeronautical Society annual conference", Aircraft Engineering and Aerospace Technology, Vol. 78 No. 2. https://doi.org/10.1108/aeat.2006.12778bac.001

Royal Aeronautical Society annual conference

Royal Aeronautical Society annual conference

Keywords: Conferences, Aerospace industry

This conference was notable for discussions of some of the most technically stimulating issues confronting aerospace today. Such was the interest aroused that each delegate was allocated two out of the three days of the conference and for this journal these were Day 1 – Technology and sustainability and Day 2 – Safety, security and operational development. As there were three parallel sections of papers, some selection has been necessary and it is hoped that this gives a good idea of the level of technology displayed.

An early paper on Day 1 was given by Dr Ian Ritchley, Chief Engineer Research and Technology – Civil; Andrew Bradley, Chief Design Engineer Research and Technology and Luke Logan, Assistant Chief Engineer Research and Technology – Civil, Rolls-Royce. This described rising to the environmental challenges of technology demonstrators. The demonstrator programmes are affordable near term low emissions (ANTLE), E3E, power optimised aircraft (POA) and SILENCER, with future endeavours envisaged. Overall, the Advisory Council for Aerospace Research in Europe (ACARE) has set targets for new aircraft and the whole industry relative to 2001. Contributions to CO₂ reduction include developments in engines, airframes and air traffic management (ATM). The engine ACARE environmental targets for 2020 are the reduction of perceived external noise by 18 db cumulative, reduction of NO_x emissions by 80 per cent and reduction of fuel consumption and CO₂ emissions by 20 per cent.

European strategy towards theses targets included in the EEFAE programme are ANTLE (−12 per cent CO₂, −60 per cent NO_x), CLEAN (−20 per cent CO₂, partial demonstration −80 per cent NO_x), VITAL (propulsive efficiency, conventional fan, greared fan, contrafan) and NEWAC (thermal efficiency, intercooled and recuperative, active core). A combined reduction of 20 per cent CO₂ is envisaged from these sources.

The EEFAE programme has two vehicles, ANTLE and CLEAN, with 19 partners. ANTLE had engine assembly completed January 2005 with first start of engine in March and scheduled completion in May. This is supported by EU, DTI and the Spanish Government. The Trent500 is the baseline engine with new technologies incorporated for proving in 2006, encompassing many components in the engine.

E3E is the aero engine part of the German Aeronautics Research programme funded by the Ministry of Economics and Land Brandenburg. The Rolls-Royce Deutschland programme has five major work packages. Core 3/2 is the technology demonstrator within the programme, with testing continuing during 2006:

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  EEFAE Programme has two vehicles (ANTLE and CLEAN); 19 partners; and €101 million EU FP5 programme. ANTLE (Affordable Near Term Low Emissions) with a target 12 per cent reduction in CO₂ emission and 60 per cent reduction in NO_x by 2008.

Towards the more electric engine (MEE), there would be many changes. The POA project has 43 partners and has three platforms. These are: aircraft systems validation rig; engine systems validation rig; and virtual iron bird. EVSR is the second build of ANTLE engine which incorporates MEE technologies.

The challenges for the MEE are engine modifications, cabling, power elect5 machines. The POA milestones are that assembly of the ANTLE engine was completed by December 2005 with testing in 2006.

SILENCER has 51 companies involved in a noise reduction programme envisaged for 2008. A wide range of projects for the Trent500 are set out. Overall there are many environmental programmes for the years ahead. The Rolls-Royce “Vision” 5, 10, and 20 are for the near term, next generation, and future generation technologies. Much has been achieved and progress made towards the ACARE goals.

Performance enhancement

Mike Smith, Engineering Project Manager Research and Technology, Airbus, presented drag reduction through large winglet technologies, in which he spoke of the main geometric parameters: winglet size/length/planform, section shape/profile, cant angle and toe angle. The main direct effects on the wing are low and high-speed aerodynamics, an increase in wing loads resulting from a combination of overall changes in wing distribution and direct loads (the dominant term) on the winglet. The overall impact on the aircraft is improved aerodynamic efficiency in cruise and low speed, increase in structural weight and improved mission performance (depending on aero/weight trade).

Any winglet increases the effective aspect ratio. A large winglet is not necessarily the first choice when designing a new wing unless the span is limited, but more likely to be for a retro-fit for product improvement. The large winglet direct load dominates the design optimisation. Reduction in vortex drag is always accompanied by increased wing loads in retro-fit applications. It is important to control the winglet direct force (e.g. by variation in winglet toe angle) to obtain an optimum balance between aerodynamic drag and loads/weight. This balance will be very specific to the configuration being studied and for retro-fit applications, this will depend on the structural margins of the existing wing structure. Flexibility effects have to be accounted for when optimising wing design.

Increasing the winglet load in too far results in excessive drag due to formation of shock waves at high speed and with a risk of an early flow breakdown at low speed. Setting angle (toe) and section shape can be used to control flow breakdown on the winglet such that the device is efficient at the conditions of interest. Relatively, lightly loaded large winglets are the preferred design solution.

It is important that aero solutions for good high and low speed performance do not conflict. Cant and winglet length in combination give an effective increase in span and various solutions are possible which give similar aerodynamic results, e.g. a large winglet with small cant angle vs a smaller winglet with a greater cant angle. Thus, optimisation overall is a complex system.

Dynamic effects include flutter characteristics of the wing/winglet combination, notably the outer wing box stiffness and mass damping. For retro-fit considerations, it may be necessary to add more structural weight in addition to any modifications due to increased loads. Also, handling qualities have to be considered. Very large winglets will influence handling characteristics. In general, an increase in lateral stability can be expected and this would have to be allowed for in the development of flight control laws.

Research efforts include the aircraft wing with advanced technology operations (AWIATOR) project which is 50 per cent EC funded and has 23 European industrial/university partners. Validation and analysis is ongoing in Airbus and European research institutions, including the facilities of DLR, ONERA, LAI, etc. and analysis of flight data is in progress.

An application example is that large winglets were considered but not used for A380. The “classic” Airbus wing-tip fence was found to be the optimum solution with a good rate of exchange between drag reduction and weight increase (Plate 1). Research and technology in the AWIATOR project on the A340-300 test vehicle has a wing optimised to give3 per cent L/D improvement at low speed relative to baseline winglet and a modest L/ED advance at cruise, also relative. Improved take-off performance is available with reduced noise with no penalty at cruise, with minimal structural modification and only a small impact on wing weight.

Plate 1 Wing tip fences on large transport aircraft

The large winglet is one of several solutions, which include more span, conventional wing-tip fence, winglet, large winglet and innovative devices. The Airbus much-used wing-tip fence is an efficient compromise between drag reduction and weight increase. The more inboard loading the wing spanwise distribution, the less effective will be the wing-tip device, i.e. a retrofit application will increase the wing twist and will move the load inboard. Flexibility effects, therefore, must be fully accounted for. Metallic wings and CFC wings have a different balance of parameters for the optimum solution. On metallic wings, large winglets have mostly been used for retrofit applications. CFC may give new ideas from the outset. The main driver in this case is load control.

Composite materials in wing structures

Presented by David Phipps, Head of Composite Structures Development, Airbus UK, this paper began with an overview of applications of composites to Airbus structures. For A320 single-aisle family, vertical tailplane leading edge and panel, etc. horizontal tailplane, engine cowls and flaps, spoilers and ailerons are flaps, are composites. For long range A340-600, leading edge J-nose, keel beam and pressure bulkhead also; and for A380, rear fuselage (Section 19), centre wing box, flap track beam sidewall panels, and wing ribs as well (Figure 1).

Figure 1 A380 centre wing box

These are mainly pre-preg/autoclave technology, with new materials and processes applied wherever reasonable. Examples include automated tape laying, pre-preg – fibre placement and liquid resin infusion (LRI), as well as resin transfer moulding (RTM).

Various research projects in lateral wing technology are scheduled for the years ahead and include the high load input which is a 6 m wingbox with pre-preg skins and which has now finished testing. Also, the TANGO wing design, which is a European 5th Framework led by Airbus UK, with 21 partners. The TANGO lower cover is by Airbus in Stade, Germany using LRI skin, Saertex NCF and RTM5 resin, NCF RTM stringers with low-cost modular tooling and secondary bonding.

Bombardier C-series

John Holding, Executive VP, Integrated Product Definition and Planning, of the New Commercial Aircraft Programme, Bombardier Aerospace, detailed the 100-149 seat market with plans for the C-series. These will be designed in 110 and 130-seat versions with improvements including 15 per cent better operating costs, 99 per cent reliability and enhanced passenger appeal and operational flexibility, with other, older types forced out of the market.

The C-series will have the right mix of two class seating to serve key city pairs, with high frequencies possible and high dispatch probability. The overall programme schedule includes 2005 launch, first flight of the 110-seat version in 2008 and EIS in 2010. An integrated collaborative framework is anticipated with new tools and processes. Unlike many competitors, this series is designed specifically for one sector of the market.

Boeing 787 – environmental leader

Given by Billy Gloverr, Director Environmental Performance Strategy, Boeing Commercial Airplane, he spoke of the three versions or the Boeing 787 (Plate 2), which is the quietest for airport communities such as Heathrow and the most efficient per 100 passenger km, assuming average modal load factors. The cabin altitude reduction from 8,000 to 6,000 ft incorporated shows benefit for a smoother ride.

Plate 2 Boeing 787 Dreamliner

There is enhanced gust suppression technology and advanced airflow management with cleaner, healthier air, as well as a quieter cabin. The cabin has better lighting and more headroom, four-in aisle (wider than competing models), wider seats, and large passenger windows and overhead bins. The development schedules the firm configuration in 2005, first flight in 2007 and deliveries in 2008. The three models are as follows: 787-3, 296 pax, 1,500 NM, 787-8, 223 pax, 8,500 NM, 787-9, 259 pax, 8,300 NM.

Environmental challenge

Colin Beesley, Head of Environmental Strategy, Rolls-Royce, dealt with the view from an aero engine company and began with the activities in which Rolls-Royce involved, including external environmental reporting, active participation in emissions trading and investment in technology on products that have outstanding environmental performance. The company is also a member of the Dow Jones Sustainability Group Indices and committed to work with others to reduce the environmental impact of aviation as well as supporting the industry’s environmental issues.

Emission trading (Figure 2) is ideally suited to global environmental issues such as accumulation of greenhouse gas (GHG) emissions and Rolls-Royce is “learning by doing” by participating in two voluntary emissions trading schemes in the UK and in the USA (Chicago exchange). ACARE environmental goals are to reduce CO₂ by 50 per cent per passenger km (assuming kerosene remains the main fuel in use), reduce the perceived noise to one-half of current levels, and minimise the industries impact during manufacture, overhaul, repair and disposal.

Figure 2 Rolls-Royce operations GHG emissions

Aero engine efficiency has improved (uninstalled SFC as a function of thermal and propulsive efficiency). Aviation’s contribution to climate change is complex and there are contributions from CO₂, NO_x and contrails and cirrus cloud effects and more understanding is needed. Meanwhile, reducing fuel burn, CO₂ and NO_x as well as noise efforts, will continue. Increasing fuel efficiency could be required in the future.

Alternative fuels have to consider safety, energy, density, cost, global availability and environmental impact. Rolls Royce is looking ahead. The ACARE goals represent a significant contribution to sustainability. Society’s growing demand for aviation is outpacing the rate of aviation efficiency improvements and a combination of technology, operational improvements and emission trading is the most cost effective option for closing the gap.

Confidential reporting

On Day 3, the History, Achievements and Future Prospects of CHIRP were detailed by Peter Tait of UK CHIRP. He began by saying that although commercial air accident rates are low, they remain relatively constant. A major challenge is identifying key causal factors. Improving the quality of feedback from professional groups through mandatory reporting is important but is less successful on human factors related aspects. Confidential reporting systems were introduced to capture this information. The introduction of UK CHIRP was in 1982 for flight crew members.

After the first year the principal areas of concern were fatigue/rostering, poor crew interaction and inappropriate crew actions. In 1986, the programme was extended to Air Traffic Control staff. Issues raised in CHIRP reports fall into two broad categories. The first is a number of reports received on the same or a similar that might be indicative of a trend. The second is reports related to a discrete incident that the reporter considers to be worthy of wider awareness. Several examples of these two are included in the paper.

Future prospects

With the introduction of other systems, it has been questioned whether such a system as this is necessary, but evidence is that reporters prefer to raise some safety-related issues on a confidential basis. It is important that such safety-related information be shared both nationally and internationally. One introduced in 2000 is maintenance error management system in which CHIRP’s role has been to develop and manage a secure website/database to facilitate the procedures. This means that the confidential reporting processes permit sensitive information derived from company maintenance investigations can be shared more widely.

Birdstrike risk

This subject was discussed by Dr John Allan, Head, Birdstrike Avoidance Team, DERA Central Science Laboratory. The extent of the problem is 231 lives lost in civil aviation, 80 aircraft lost and a considerable financial burden. There are 700 strikes per year in the UK and the probability of catastrophe is estimated at between one in ten and one in ten movements. The actual number of strikes is probably between two and five times those reported. Measuring the site specific risk is important for each bird species identified, frequency and severity.

Controlling the risk means that the habitat management and bird scaring techniques have changed little in 30 years. Recent developments include use of lasers and dogs to deter birds. Effective control on the airfield is possible with sufficient investment in manpower and equipment. In 2003, ICAO implemented new standards for airport bird control. Bird management off the airfield includes planning control, liaison with neighbours, publicity, consultation with conservation organisations, etc. and requires a careful, considered approach based on good science.

Bird detection is by radar, thermal imaging, image intensifiers, acoustic array, and of course, sight. Bird avoidance models are useful and are already in use for military pilots on low level operations.

Security – cornerstone of aviation safety

This was presented by Geoff Want of British Airways who began by commenting on one interesting year which included security breaches, temporary suspension of flights to Nairobi, tanks at Heathrow, passenger found with grenade, and temporary as well as temporary suspension of flights to Saudi Arabia. The events of September 11 were watershed for aviation security, with customer confidence to be restored including the locked cockpit door (Plate 3). Reassurance was most important and after September 11, 32 per cent of UK customers wanted to avoid flying, and there was need to communicate about what we were doing.

Plate 3 Locked and reinforced cockpit door

There was the issue of a customer safety and security reassurance leaflet. Three months after September 11, customer confidence increased 50 per cent in the UK and we needed to build on this to ensure our business recovered. Security initiatives included 100 per cent baggage screening, customer blacklists, launch of yellow cards on the ground, roll-out of Phase 2 of locked cockpit doors, closed circuit television, criminal security checks, and a ban on sharp objects.

Prevention is better than cure and the key to security in the air is security on the ground, and where necessary, additional measures. In Germany, additional checks on staff going airside, and in the USA implementation of additional baggage screening. Further measures are being evaluated.

The question is – who pays for security? Should governments pay? Now is the time to reflect on what has been achieved and what needs to be done. We support the drive for consistency across member states. In other words, do not let the terrorist win.

Passenger safety – the future challenge

This was given by Dr Helen Muir of Cranfield University who noted that a large percentage of the developed world as well as others in less developed areas, can travel freely. The public perception is of accidents, which have an average of one fatality every 12.5 million passengers by UK airlines. A high survivability rate – although not too much attention is given to this figure as the majority of aircraft accidents are survivable. Being informed of safety measures is very important.

Then behaviour of passengers and their impact on emergency evacuation has also come under scrutiny, and more understanding of stress, etc. could improve emergency successful evacuations. In order to understand the factors, which influence passenger safety it is necessary to determine the causes of fatalities in accidents. Broadly, these are impact, fire and terrorism. An example of the first is Kegworth in 1989. Many fatalities occurred as a result of the initial impact and failure of structures. When fire is considered, there is typically a maximum of 2 min between the first spark and the cabin becoming non-survivable due to smoke an toxic fumes. Response to the third category that of terrorism, has been to introduce air marshals on many flights.

From analysis, it has been possible to build up a picture of the factors affecting survival. There were many similarities between the accident at Manchester in 1985 and that at Calgary in 1984 in that they were both caused by an engine fire at take-off. However, they differed because at Manchester there were 55 fatalities whereas at Calgary, everyone survived. There are a great many questions which remain unanswered about the behaviour of people in emergencies, and it may be that one of the primary reasons for the differences in behaviour between the orderly and disorderly situations must arise from the motivation of individual passengers.

A major programme of research to produce experimentally a simulation of this behaviour has been conducted in which an incentive payment system has been used to simulate motivation and behaviour. It was found from the tests that not only were there differences between the evacuation times in actual accidents and the times when the aircraft was tested for certification, but also features of the cabin layout which caused blockages and congestion when passenger behaviour was disorganised. Fear, anxiety, affiliative behaviour (involving movement towards the familiar) and focused attention, were identified and the extent to which some of these reactions and behaviours occur (together with the performance of the crew) will be major determinants of the occurrence of orderly or disorderly behaviour.

Particular attention is directed to very large transport aircraft in the future. Large slides will require extra care. From research and analysis the industry has made changes and the challenge is to ensure that the increased size of airframes continues the impressive the impressive level of safety.

Detection of foreign object debris

Patrick Beasley of QINETIC described the Tarsier Millimetre Wave Radar System for detection of foreign objects (Figure 3). It has been calculated that foreign object damage (FOD) costs the aviation industry $4 billion a year. The Concorde tragedy highlights the problem. Reliable detection is the requirement and challenges to airport operations are to improve safety, maintain or increase capacity, minimise operational workload and reduce business risk.

Figure 3 The Tarsier System

The key to radar FOD detection is to minimise clutter background, have dynamic rain capability and the ability to reject false target. The equipment must reliably detect and locate low radar cross-section targets in any adverse or fine weather conditions. The design philosophy is to minimise antenna size with 94 GHz and use FM CH with good range resolution dedicated to FOD detection with no compromise.

Results of FOD detection have been successful, including several sharp objects.

The system site survey will be conducted by QINETIC who will arrange and oversee radar installations and perform full site acceptance and commissioning tests, as well as support packages.

Introduction of single European sky

The practicalities and implementation of the single European sky (SES) were detailed by Alexander der Kuile, Secretary General of CANSO (Civil Air Navigation Services Organisation). CANSO is the global trade organisation of ANS providers and is open to all aviation industry players with many international members. It is ATM on business principles.

Current trends in ATM include political awakening to address the institutional model, liberalisation of air navigation services and changing roles of Government. The future of ATM is a global system. Previously in Europe, there was fragmentation, and the EU will harmonise all sectors with one approach, SES with 25 states plus CH and N.

Helicopter Operations Monitoring Programme

Captain Nick Norman, Helicopter Operations Monitoring Programme (HOMP) Manager, Bristow Helicopters (BHL), spoke of the identification and mitigation of operational hazards. BHL has been involved with HOMP for some years and increased this fleet from five aircraft to full implementation of its European helicopters, with further expansion planned into Africa, Asia and Australia. HOMP is the application of flight data monitoring (FDM) to helicopters. Human factors are a key issue with HOMP and ensuring pilot trust is very important. The programme has been running for five years and a significant number of incidents have been identified.

HOMP began in 1999, initially on a small scale because of the existence of HUMS, the benefits quickly became apparent. The programme operates by analysing FDR data that is downloaded onto HUMS ground stations and careful review of events is a key area. Once the events are validated they are added to the database. Pilot trust in the system is vital and needs to be carefully guarded. Examples of events show that HOMP provides information about the hazards associated with rotary wing operations that would otherwise not be appreciated.

Terry Ford