The overall objective of ADELINE was to identify technologies enabling the further development of innovative, fully European air data systems for implementation on new transport aircraft around 2007.
Actual air data equipment is composed of a large number of individual probes and pressure sensors. This equipment delivers vital parameters for the safety of the aircraft's flight such as air speed, angle of attack and altitude. The loss of these data can cause aircraft crashes especially in case of probe icing.
The objectives of ADELINE were to increase aircraft safety by reducing the possibility of air data system failure, to develop simpler, more reliable and safer air data equipment, to decrease direct possession costs of present air data systems, and to make a step change in air data system reliability, fault detection and susceptibility to blockage by foreign objects.
Reliability will be increased by the use of innovative measuring systems with a better resistance to external hazards, new materials and coatings for the probes to increase abrasive resistance, and to increase lifetime and maintain constant lifetime performance. Also new de- and anti-icing technologies using new innovative heating elements and a new auto test for the pressure sensor to detect erroneous information will contribute.
The cost of the system will be lowered due to the reduction of the number of parts per probe and the integration of the sensors in the probes with innovative packaging, which will allow the elimination of all pneumatic tubing and connections. The use of self-regulated PTC heaters remaining at a constant temperature will allow the elimination of the expensive Probe Heater Computer.
ADELINE helped provide a better knowledge of existing air data architectures and their shortcomings in order to propose better-adapted, more reliable and cheaper air data equipment to aircraft manufacturers in the future. Thanks to the consortium skills, ADELINE also allowed the identification of emerging measurement techniques, materials, ceramics, coatings and packaging techniques, which will allow improved resistance to wear and corrosion of probes, ensure a more efficient way to de-ice probes with no overheating risk and decrease the overall cost of air data architectures by reducing the number of units.
The requirements for new air data systems were defined in terms of safety, reliability, fault tolerance, operational performance, installation and maintenance. The typical architectures used by the main manufacturers in this field was analysed in terms of these criteria.
New measurement principles for aerodynamic probes were researched in order to reduce their sensitivity to the external environment. Candidate materials, coatings and manufacturing technologies, which could be used to improve corrosion resistance and decrease cost, were identified. Potential technologies for probe anti-icing and de-icing were identified. Innovative ways to integrate additional functionality into the housing of the MEMS pressure sensor were researched.
Laboratory mock-ups were tested in a dry wind tunnel in order to validate their aerodynamic shape and the new measurement principles. Existing MEMS pressure sensors were modified to include the self-test principle to evaluate the sensitivity and the repeatability of the auto test. Other mock-ups were tested under corrosive conditions to evaluate the most suitable cast material, casting technology, coating material and coating technology.
Two functional mocks-up were tested in dry wind tunnel and icing conditions to evaluate their compliance with the requirements of the equipment specifications. The tests were divided in two categories: metrological tests and environmental tests. Accelerated lifetime tests were performed and the mock-ups were also tested in flight conditions.
To achieve the Project objectives, a consortium of 8 partners with all the required skills was established as follows: 2 SMEs, 1 industrial, 3 academic institutes and 2 research centres. The project was organised in 5 work packages which allowed:
- the definition of the system architecture
- the development of innovative principles and technologies
- the development and the flight tests of 2 different functional mock-ups.
ADELINE helped the provision with better knowledge of existing air data architectures and their shortcomings in order to propose better-adapted, more reliable and cheaper air data equipment to aircraft manufacturers in the future. Thanks to the skills of the consortium, ADELINE also allowed the identification of emerging measurement techniques, materials, ceramics, coatings and packaging techniques. These will allow improved resistance to wear and corrosion of probes, ensure a more efficient way to de-ice probes with no overheating risk and decrease the overall cost of air data architectures by reducing the number of units.