PARIS — Advanced studies on a planned Anglo-French unmanned combat aerial vehicle technology demonstrator are under the spotlight for Onera at the Paris Air Show, according to the head of the defense division at the French aerospace research center.

"The leading presentation is FCAS (Future Combat Air System)," Franck Lejeune told a June 12 news conference. Britain and France signed the UCAV program in 2012, with Dassault Aviaton, Safran and Thales working under the direction of the Direction Générale de l'Armement, or DGA, France's procurement office.

Onera is working on various aspects of stealth as the program seeks to build "the most stealthy drone possible," he said. Stealth will be "the most important factor in survivability." Stealth will be explored in electromagnetic warfare, infrared, on-board intelligence and navigation without GPS, he said. Other studies include on-board and miniaturized sensors, in-flight refueling, and aerodynamics.

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A first demonstrator is due in 2025, with production in 2030, he said.

The research center is also working on expected threats against the UCAV in 2030, with the DGA stand displaying Onera's Blade simulator setting out a future system of systems for air combat, he said.

Onera last year conducted wind tunnel tests for Airbus Defence and Space, which commissioned tests for an A400M in-flight refueling system for helicopters, he said. The results were delivered in May 2016, and Airbus Defence and Space and its British subcontractor Cobham have been working on a system.

That helicopter refueling is one of the A400M requirements that posed a problem for Airbus and required extra effort to deliver. France ordered four C-130Js as a stopgap measure because of late delivery of the A400M, with two of those aircraft fitted for helicopter refueling.

Another significant research project includes a long-range detection pod for radar and optronics, flown on a Mystere 20 jet, Lejeune said.

The center has also designed and developed an airborne pod, dubbed Sysiphe, which uses multi-spectral optronics and infrared technology to detect camouflaged troops and vehicles at long range. The pod is mounted on a Dornier plane flown by DLR, the German research center.

Singapore is a significant and rising partner, working with Onera on radar, optronics, surveillance and laser weapons, he added.

In space research, Onera is one of the five-strong Association of European Space Research Establishments, which brings together France, Germany, Italy, the Netherlands and Spain. They are working on a road map to coordinate work for 2030 under the guidance of the European Space Agency, said Jean-Claude Traineau, head of the space division. Asked why Britain is absent from that group, he said Onera worked with some British universities, including University College London.

Defense research accounted for 40 percent of 2016 orders for Onera, which was awarded €130.3 million (U.S. $145.8 million) worth of orders, up 23 percent from the previous year, with a total budget of €235 million. Onera, which reports to the French Armed Forces Ministry, received €105 million in state subsidies. The center reported a 2016 profit of €4.8 million.

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