A senior US diplomat has threatened to use the Lockheed Martin F-35 programme as a retaliatory tool against Turkey for acquiring a sophisticated air defence system from Russia.

Assistant secretary of state for European and Eurasian Affairs Wess Mitchell’s remarks during 18 April hearing in Congress escalated a simmering confrontation with a NATO ally and combat partner against ISIS, which agreed to acquire the Almaz-Antey S-400 Triumf system even as it plans to take delivery of its first F-35A later this year.

Breaking from a string of ambiguous statements by the Trump Administration, Mitchell’s testimony made specific threats of potential retaliation if the Turkish government follows through on the acquisition of the S-400 system.

“Ankara claims to have agreed to purchase the Russian S-400 missile system, which could potentially lead to sanctions under section 231 of [countering America’s adversaries through sanctions act] and adversely impact Turkey’s participation in the F-35 programme,” Mitchell says.

The S-400 is Russia's most advanced surface-to-air missile system on the export market. It's advertised with an "anti-stealth range" up to 81nm (150km).

In the past, US officials have complained that Turkey's S-400 systems would not be interoperable with NATO's networks. But the acquisition also raised concerns that Turkey's possession of the S-400 and the F-35 could be used to compromise the latter, with Russia and its allies gaining invaluable intelligence.

It was not clear specifically how Turkey’s role in the F-35 programme could be affected, but the Trump Administration has several tools at its disposal.

Turkey joined the F-35 programme in 2002 as a level 3 partner, investing $195 million in the system development and demonstration phase. Turkish Aerospace Industries (TAI) is deeply involved in the F-35A supply chain, supplying composite parts since 2008. TAI also is a secondary source to Northrop Grumman for the centre fuselage, with a long-term agreement to supply 400 of the complex assemblies to Lockheed over the life the programme.

The Turkish air force, meanwhile, plans to acquire 100 F-35As. The first batch of 14 are already purchased, with deliveries scheduled to begin later this year. A total of 30 F-35As are scheduled for delivery to the TuAF by the end of 2022.

Source: FlightGlobal.com