Development of an Innovative Acoustic System for the Improvement of Co-operative Air Traffic Management
New technology has ensured a new era in airport safety. Human error, bad weather and ineffective ground radar can all have serious consequences on airport safety, increasing the risk of an accident. New complementary airport safety systems currently under development promise to avoid such incidents in the future.
'Though technology has come a long way in recent years toward improving airport safety, it is evident that current systems using ground radar or cameras to detect aircraft and other vehicles suffer from deficiencies', says Haibin Gao, a researcher at Saarland University.
New, more efficient and more accurate systems are therefore needed to prevent accidents, especially as the world's skies and airports buzz with an ever-increasing number of commercial and private aircraft. Saving lives is obviously the central goal of any such safety improvement. But they can also provide significant economic benefits. Reducing the number of near misses between planes, and between planes and ground vehicles - thousands of which occur worldwide each year, primarily as a result of runway incursions - would save airlines and airport operators billions of Euros in lost time and efficiency. By being able to pinpoint the exact location and course of an aircraft or vehicle, airports would be able to maintain current capacity even during periods of bad visibility.
Capacity problems are one of the other major concerns of airports and aviation authorities at present. With air traffic increasing at an average rate of 6 % per year, airports, both large and small, are feeling the strain of managing more and more planes within their limited facilities. The expansion of existing airports with more runways and other facilities or the construction of new ones is becoming less feasible due to environmental concerns. The solution therefore consists of providing the tools to airports that enhance the ability to handle more aircraft and to do so safely.
Efficiency gains can also be realised during takeoffs and landings by improving the utilisation of available ground and air space while at the same time reducing the risk of accidents. The SAFE-AIRPORT acoustic system, the first to employ phased array microphones in civilian aviation, will provide these benefits by alerting controllers of the deviation when a plane leaves its flight path up by over six nautical miles.
Development of the system includes a complete simulation through the development of software that includes external acoustic environment modelling, and the relative test condition scenarios to allow control of the system requirements and performance. The project will be realised by means of two distinct steps. The first step (STEP 1) of 18 months (financed by the present contract) includes design and development of one sensor. The second step , also 18 months in length (not financed by the present contract), performs compatibility testing of the first sensor and the production of the second sensor. The system will be used to both guide system design, and to verify system performance in collision-risk situations.
STEP 1 will involve:
- System and Testing Requirements;
- Simulation Software Design and Development;
- System Software Design and Development;
- Phased Array Design, Simulation and Development;
- Electronic Hardware Design and Development;
- Exploitation; and
- Project Management.
The SAFE-AIRPORT project developed an innovative acoustic system based on two Passive Phased Array Microphone antennas capable to discover and track aeroplanes up to at least sixth nautical miles distance in air and on ground. The system consists of two acoustic sensors, to be used in open environments, and a control unit linked to the sensor with fibre optics connection, with a control console, managed by an operator, to be installed inside the airport structure. Data survey portability to radar platform and data visualisation and exchange are compatible with 'Eurocontrol Standard Document for ATS ADEXP [DPS.ET1.ST09-std-01-01]'.
The system is completely integrable with airports air traffic management procedures and it is an effective air control system for ATZ (Aerodrome Traffic Zone), autonomous for smaller airports, and has been integrated with standard control systems for larger airports.
The main advantages of SAFE-AIRPORT system in respect to radar systems is the lower cost and that the electromagnetic and acoustic devices are pollution free. The system has been able to detect aircraft within 5 nautical miles. Tests have confirmed simulation results, except for those at the maximum range of reliable limits.
'Because they do not produce electromagnetic radiation like radar or any noise pollution, multiple arrays can be used to detect aircraft from their engine and aerodynamic noise with very high precision', explains SAFE-AIRPORT coordinator Alessandro Ferrando at D'Appolonia in Italy. 'Also, unlike radar, they can detect aircraft with composite, non-metallic bodies that are likely to be used widely in civil aviation in the future'. What's more, the system costs of these technologies will be in such a range that small airports will be able to make the necessary investments, thus improving safety and augmenting capacity in a sector constantly growing.
Three related 6th Framework Projects have developed an alternative to ground radar and are designed to improve safety.
'They are all very innovative and they are likely to have a vast impact on the future of air traffic control at airports: they could even be a cheap alternative to ground radar', says Gao, who is developing magnetic sensors to detect and track aircraft in another IST project.
Two other IST projects, AIRNET and ISMAEL, are also applying emerging technologies to reduce the risk of accidents on the ground and during takeoff and landing. Most importantly they are all complementary, opening the door through their collaborative efforts to multi-sensory detection, tracking and identification systems for planes and ground vehicles. They all expect to have commercial products on the market within two to three years.
G.R.A.S. Sound & Vibration APS
D'Appolonia S.p.A.; Universita Degli Studi di Roma; CRB Software Division S.r.l.; Aeroporti di Roma S.p.A.
Hytec Electronics Limited