Rendering of possible new fighter as part of the French-German future combat air system (FCAS). Image: Airbus

European defense modernization plans for fixed wing and rotorcraft will take center stage at this year’s Paris Air Show, which is scheduled from June 16-23 at Le Bourget Exposition Center.

The show will feature dozens of commercial and military aircraft, including the Airbus Eurofighter, Aliaca drone, and EC665 Tiger attack helicopter; Dassault Aviation‘s Rafale fighter; the NH90 Caiman helicopter by NHIndustries–a consortium of Airbus Helicopters, Leonardo, and Fokker Aerostructures; the Lockheed Martin [LMT] F-35, and the Boeing [BA] P-8 Poseidon.

“This is a pivotal moment in European aerospace,” said Richard Aboulafia, vice president of The Teal Group. “It’s obvious Eurofighter production will end in the next few years. The Rafale and Saab‘s Gripen will likely sunset in 2030 to 2035.”

In addition, “the future of the European helicopter business needs to be decided now,” he said. “The [Leonardo] AW101, the NH90, and the Tiger are all ramping down heavily and there’s not a lot coming.”

It is thus far unclear whether European nations will embark on any cooperative high technology helicopter venture, such as the U.S. Army’s Future Vertical Lift program.

Whether the Franco-German-Spanish Future Combat Air System (FCAS) will advance or wither on the vine is also anybody’s guess. FCAS is a notional sixth generation fighter to replace the Rafale and Eurofighter Typhoon. The Royal Air Force is pursuing a separate sixth generation fighter–Tempest–with BAE Systems.

The latter company has had no presence at the Paris Air Show in the last several years.

At this year’s show, Dassault Aviation CEO Éric Trappier said that his company will present “what could be a demonstrator for the Next Generation Fighter under the Future Combat Air System (FCAS).”

On FCAS, Airbus has said it is taking the lead on the unmanned portion, while Dassault is to be in the driver’s seat on the manned aircraft. A key issue appears to be whether French authorities will agree to technology cooperation and whether German government officials will allow the program to move forward without excessive regulatory oversight.

“Brexit has resulted in this really weird realignment,” Aboulafia said. “To what extent is Brexit a hiccup, and to what extent is it changing everything?”

“If somehow Brexit results in the United Kingdom’s severing of industrial and political relations with the continent, then FCAS might have a chance, but it probably won’t and Brexit will likely be remembered as an unpleasant process,” he said. “Britain is still 20 miles off the French coast, and it’s still part of NATO.”

If Brexit is just a momentary peeling away for Britain, “Tempest will end up looking like a much more attractive program” to other European nations, Aboulafia said.

On the U.S. side, the Navy and Air Force are pursuing their own plans for sixth generation fighter aircraft. Asked about those plans last week at a pre-Paris Air Show briefing and whether the plans could involve significant transnational cooperation or instead a mostly U.S. approach, Undersecretary of Defense for Logistics and Sustainment Ellen Lord demurred and said simply that she expects a “robust competition.”

Given the U.S.’ political stance and the national defense strategy of preparing for near peer conflicts, it appears that the U.S. will endeavor to guard its sixth generation fighter technology fairly closely.

Lord and other U.S. officials, including Air Force Assistant Secretary for Acquisition, Technology and Logistics Will Roper and Army Lt. Gen. Charles Hooper, the director of the Defense Security Cooperation Agency, are scheduled to attend this year’s Paris Air Show.