PARIS — The European defense and space agencies said April 26 they had successfully demonstrated the ability of an unmanned aircraft using satellite links to communicate with air traffic controllers to operate safely in civil airspace, including the performance of a collision-avoidance maneuver.

The Desire project, or Demonstration of Satellites Enabling the Insertion of Remotely Piloted Aircraft Systems (RPAS) in Europe, is jointly funded by the European Defence Agency, an arm of the European Union, and the 20-nation European Space Agency.

The flight demonstrations from the San Javier Air Base in Spain, which ended April 24, were designed to test whether ground pilots located beyond line-of-sight communications to the RPAS, using a link to a satellite in geostationary orbit, could interact with civil air traffic controllers with sufficient speed and precision to meet safety requirements for the RPAS they were flying.

The demonstration was managed by an industrial team led by Indra of Spain and including AT-One of Germany and Holland; satellite fleet operator SES of Luxembourg; Thales Alenia Space of France and Italy; and Italy’s CIRA aerospace research institute.

The unmanned aircraft used was a Heron 1 medium-altitude, long-endurance drone developed by Israel Aerospace Industries (IAI). With a 17-meter wingspan and a takeoff weight of up to 1,270 kilograms, Heron 1 is designed to operate within a 350-kilometer radius of its ground controllers for missions of up to 45 hours at more than 9,000 meters in altitude, according to IAI.

During one of the flights, a manned aircraft from the Spanish Air Force Academy was directed on a trajectory for a head-on collision and a 90-degree collision. The ground controllers of the drone demonstrated that the satellite link was sufficient to permit them to follow air traffic control instructions to change course.

The six-hour flight on April 24 took off at 11 a.m. and climbed to 6,000 meters. The takeoff was timed to coincide with civil and military traffic from the airbase and from nearby Murcia Airport.

The RPAS carried radar and video payloads and was also equipped with an Automatic Identification System receiver to capture data on maritime traffic. Maritime surveillance is one of the applications foreseen for these unmanned aerial systems.

EDA and ESA are jointly managing several projects involving unmanned aerial vehicles, whose development in Europe has been stunted by the absence of a harmonized legal regime for their operation in civil airspace.

Peter B. de Selding was the Paris Bureau Chief for SpaceNews.