As the flagship of the 21st century, the A380 will not only be the most spacious civil aircraft ever built, it will also be the most advanced - representing a unique technology platform from which all future commercial aircraft programmes will evolve.
Airbus has a long and successful record of pioneering new technology in an evolutionary and responsible manner, to ensure better aircraft performance, lower operating costs, easier handling and greater comfort. This is the cornerstone of Airbus’ success in the marketplace, enabling Airbus aircraft to retain a strong competitive edge over other products, and translates into immediate benefits for customers, operators, pilots, crews and passengers alike.
The A380 takes this philosophy into the 21st century, and an array of new technologies for materials, processes, systems, and engines have been developed, tested and adopted. All technology considered for the A380 is carefully studied to determine its effects over the lifetime of the aircraft, and is selected for its proven maturity and long-term benefits. Each selection therefore contributes to attaining or bettering the programme targets, in keeping with the basic design tenets of reliability, low seat-mile cost, passenger comfort and environmental friendliness.
Moreover, while offering all the advantages of a completely new design, the A380 will extend the benefits of Airbus family commonality to the very large aircraft sector. Thanks to the same cockpit layout, procedures and handling characteristics, pilots will be able to make the transition to the A380 from other Airbus fly-by-wire aircraft with minimal additional training.
MaterialsA number of innovations introduced on the A380 will ensure considerable weight savings despite the aircraft’s prodigious spaciousness, and tests show that aerodynamic performance of the aircraft will also be significantly enhanced. Better aerodynamics and lower airframe weight reduce the demands placed on engines and translate into lower fuel burn, reduced emissions into the atmosphere and lower operating costs.
For instance, based on the excellent in-service experience gained on its existing products, Airbus is extending the use of carbon fibre reinforced plastics (CFRP) to the A380. The A380 will be the first Airbus aircraft ever to boast a carbon fibre central wingbox – representing a weight-saving of up to one and a half tonnes compared to most advanced aluminium alloys. A monolithic CFRP design has also been adopted for the fin box and rudder, as well as the horizontal stabiliser and elevators. Furthermore, the upper deck floor beams and rear pressure bulkhead will be made of CFRP, while the wing covers will be constructed from advanced aluminium alloys. The fixed wing leading edge will be manufactured from thermoplastics, and secondary bracketry in the fuselage (serving, for example, to hold the interior trim) is also likely to be made of thermoplastics. Further applications of thermoplastics are under investigation, such as for the ribs in the fixed leading edges of the vertical and horizontal stabilisers.
An estimated 40 per cent of the aircraft’s structure and components will thus be manufactured from the latest generation of carbon composites and advanced metallic materials, which, besides being lighter than traditional materials, offer significant advantages in terms of operational reliability, maintainability and ease of repair.
A new lighter and even more resistant material will also be used for the first time on a civil airliner after intensive trials. The upper fuselage shell of the A380 will be fashioned from GLARE, a laminate alternating layers of aluminium and glass-fibre reinforced adhesive. In addition to being some ten per cent less dense than aluminium – for a weight-saving of around 800 kg – GLARE has proven superior in terms of fatigue as well as fire and damage resistance. Indeed, testing has demonstrated that an artificial crack subjected to thousands of flight cycles barely increases in size. The new material also resists exceptionally well to corrosion with the first glass-fibre layer preventing any penetration beyond the superficial aluminium coating. GLARE uses a hot bonded manufacturing process but is repaired in the same way as standard aluminum.
Following an in-depth study, two test flight campaigns and numerous laboratory and simulator tests, A380 engineers have also succeeded in moving the aircraft’s centre of gravity aft by around six per cent. This change in centre of gravity, coupled with an enhanced fly-by-wire system, has led to a reduction of approximately 40m2 in the area of the vertical stabiliser and a consequent saving in weight, while preserving the stability of the aircraft in-flight.
The net weight-savings resulting from these and other innovations discussed below, allow the A380 to weigh in at around 240 tonnes – a full ten to 15 tonnes lighter than a similar sized aircraft using 747 technology.
SystemsAnother weight saving feature is the use of an increased pressure for the A380’s hydraulic systems. For the first time ever in civil aviation, the A380’s hydraulic systems will have an increased pressure of 5,000 pounds per square inch (psi), as opposed to the traditional 3,000 psi. This increase in pressure allows the necessary power to be transmitted with smaller piping and hydraulic components. The reduction in the size of components, unions and piping not only lowers the weight of the aircraft by around one tonne but also improves its maintainability. Military aircraft have already been using these high pressure systems for many years and the change is an evolutionary move which has stood up well to qualification testing. Trials with existing hydraulic fluids and components have shown that the fluid does not degrade under the higher pressures and no evidence of erosion has been found.
In addition to the increased hydraulic pressure, a dual architecture for the flight control system has been implemented, featuring four independent primary flight control systems with two different configurations. Two of these systems use a conventional hydraulic actuation system whereas the other two feature local electro-hydraulic actuators for the control surfaces. The aircraft can be controlled using any one of these four systems. This brings system separation and redundancy in flight controls to a level never achieved before on an aircraft, whether civil or military.
Environmental FriendlinessThe A380 will moreover benefit from a completely re-designed double spool air generation system, which is more efficient in terms of thermodynamic cycles, provides more flexibility between different air generation requirements on the ground and, at cruise, takes up less space and offers more redundancy and damage-resistance. Airliners are generally equipped with two air-conditioning packs, each of which converts high temperature, high pressure bleed air (from the compressor stage of the engines) into pressured cabin air at room temperature. Instead of using four such packs to generate the necessary air, the A380 will be equipped with two innovative double-packs, in which each unit performs separate functions of the overall cycle. This more robust approach provides valuable systems redundancy as well as greater overall efficiency.
The A380 will help cope with growing passengers numbers without negatively impacting the environment, thanks to significantly reduced noise and emissions levels. In spite of its higher weight and thrust requirements, the A380 will make less noise than its closest competitor while carrying 30 to 50 per cent more people. Current noise certification rules (ICAO “chapter 3”) will be met by significant margins and the A380 will be compliant with the strictest local noise regulations, classified QC2 for departure from London’s busy airports and QC1 for arrival.
For ground operations, the A380 can taxi with only two engines if required, will use only two thrust reversers and will employ a low-noise auxiliary power unit to help eliminate any noise concern.
The A380’s new generation engines will also surpass the requirements of the latest regulations for the landing and take-off cycle. Because of its larger capacity, the A380 will make better use of available take-off and landing slots, thus reducing fuel wasted in airborne delays and holding patterns.
The economic fuel consumption of the A380 – around 13 per cent lower fuel burn than its closest competitor – will also help reduce the impact of exhaust gases on the atmosphere. Indeed, the A380 will be the first long-haul aircraft to consume less than three litres of fuel per passenger over 100 kilometres – a fuel burn comparable with that of a mid-sized automobile.
Airport CompatibilityThe A380 has been designed in close collaboration with major airlines, airports and airworthiness authorities. For the past six years, Airbus has been working with representatives of more than 60 international airports to ensure the most cost-effective integration of the aircraft commercial operations. As a result, all the A380’s major destinations are working to a master plan enabling them to accept the aircraft when it enters into service.
The A380 is in many ways compatible with the facilities used today by existing large aircraft. The A380’s large wings and new engines will provide better take-off and landing field performance than that of current large aircraft and therefore require a shorter runway. In addition, thanks to the 20-wheel main landing gear, the A380’s pavement loading will remain within the parameters of inservice aircraft. The footprint of the A380 landing gear is comparable with that of existing aircraft and does not require new runways.
The A380 cockpit is midway between the two decks, which means the pilot sits near the aircraft centre-line providing an enhanced view. This, alongside cameras located in the tail fin and on the belly, allow accurate placement of the aircraft.
At the gate, the A380’s two decks and wide forward stairs will allow turnaround times comparable to those of today’s largest airliner, even only if single deck access is possible.
With traffic and airport congestion increasing annually, the A380 represents a positive investment for key international hubs as it will contribute to the resolution of the congestion problem at major gateways. Airbus’ analysis of this issue has been irrefutably confirmed, both implicitly, through industry-wide participation in the programme from its outset, and explicitly, through the already immense success of the A380 on the market.
ProcessesSeveral innovative manufacturing techniques have been selected for use on the A380 programme, some of which have proved so advantageous they have gone into series production on other existing Airbus aircraft programmes.
One example is laser beam welding which is used to attach the “stringers” (longitudinal reinforcements) of the lower fuselage shell instead of traditional riveting. This technique not only engenders a potential weight reduction, it is also much faster than conventional riveting – eight metres of stringers can be laser beam welded per minute. The method includes a built-in automated inspection unit and tests run on the resulting structures to determine damage and fatigue tolerance have demonstrated that they behave as well or better than conventional alloy construction. A further major advantage of this technique is that it eliminates fasteners, and thereby the major source of corrosion and fatigue cracks.
Laser beam welding went into series production in 2001, for the manufacture of the rear fuselage lower skin on the single-aisle A318.