Patented by EADS’ corporate research and technology arm – EADS Innovation Works – and Airbus, this design applies specially-shaped aluminium “diffraction grating” panels to prevent a building from scattering signals broadcast by the airport’s Instrument Landing System (ILS), used during aircraft arrivals in reduced visibility conditions.
A software simulation tool called ELISE determines how these aluminium panels should be applied, and confirms their effectiveness in making a building “stealthy” in relation to the ILS signals. ELISE results from a collaboration of Airbus, EADS Innovation Works and the French ENAC aviation university, with this software tool taking into account such factors as a building’s size, orientation and location relative to the ILS installation.
The first use of this technology is on Airbus’ own C65 hangar, which has been built in the A330 final assembly area at Toulouse-Blagnac Airport in France. Without the diffraction grating panels, the hangar would scatter signals from the ILS at the airport’s nearby Runway 14R/32R, potentially making the landing system unreliable.
By using ELISE to determine the diffraction grating panels’ installation, the C65 hangar has become “stealthy” in relation to the ILS signals. In addition, the ELISE software simulations determined that only the building’s upper 10 metres needed to be covered with the aluminium panels for the necessary effectiveness.
With this technology now demonstrated, it is being made available through the Airbus ProSky subsidiary, thereby opening opportunities for airports worldwide to build on land that – until now – has remained empty because of potential interference with the Instrument Landing Systems.