Finland’s Patria F135 engine program reached a milestone on September 3, 2026, when Patria completed assembly of the country’s first F135 fighter jet engine at its new Linnavuori facility in Nokia. The completion was marked at a ceremony attended by Patria executives, senior Finnish defense officials and Pratt & Whitney representatives, days ahead of the first F-35As arriving at Finland’s Lapland Air Wing this autumn.

The engine is the first tangible result of a February 2026 agreement between Patria and Pratt & Whitney, an RTX business, covering final assembly of F135 engines in Finland — the powerplant for the F-35A Lightning II that Finland selected in 2021.

From Agreement to Hardware in Seven Months

Patria and Pratt & Whitney signed a broader framework contract covering F135 maintenance, repair, overhaul and upgrade (MRO&U) work back in 2024, before following up in February 2026 with the specific agreement to also handle final assembly of new-build engines. The Linnavuori facility itself, purpose-built to Pratt & Whitney and F-35 program security requirements, had its cornerstone laid in March 2025 and was handed over to Patria in October 2025.

“Patria’s part of the F-35 programme is progressing according to plan and has now entered full-scale production,” said Petri Hepola, Patria’s chief program officer for F-35. “The completion of the first F135 engine is a significant milestone and a strong start for F135 engine assembly in Finland.”

Assembly work at Linnavuori is planned to continue through 2030, generating roughly 50 direct jobs at Patria over that period. After 2030, the facility is set to shift toward maintenance, repair, overhaul and upgrade work, supporting Finland’s F-35 fleet for the remainder of its expected service life.

Patria F135 engine: Pratt & Whitney F135 engine on test stand at AEDC
File photo: Pratt & Whitney’s F135 engine, the same engine type Patria now assembles for Finland’s F-35 fleet, undergoes accelerated mission testing in a sea-level test cell at Arnold Engineering Development Complex, Tennessee. Not from Patria’s Linnavuori facility. (U.S. Air Force courtesy photo by Rick Goodfriend)

Why This Matters Beyond One Engine

A single completed engine is a modest physical achievement, but it represents Finland moving from simply buying F-35s to building the domestic industrial capability to sustain them. Retired Col. Henrik Elo, F-35 program director for the Finnish Air Force, framed the completion in those terms.

“The production line will be adapted for engine maintenance activities, and the expertise being built today will strongly support the domestic security of supply for our F-35 fleet in the future,” Elo said.

Pratt & Whitney frames the milestone in similar terms for the broader F135 support network. “Assembly of Finland’s first F135 engine marks an important milestone in strengthening the global F-35 sustainment network and expanding propulsion capability in Finland,” said Jill Albertelli, president of Pratt & Whitney Military Engines. For a NATO member bordering Russia, the Patria F135 engine program’s reduced dependence on overseas engine support has obvious strategic value during any prolonged or high-tempo operations.

More Than Engines: Patria’s Broader F-35 Role

Engine assembly is only one piece of Patria’s involvement in Finland’s F-35 industrial participation program. The company also assembles forward fuselage sections for the F-35, work that began in early March 2026 at a modernized production facility in Halli, Jämsä, and manufactures structural components including the aircraft’s landing gear doors, assembly of which began earlier this year as well.

A Fitting Detail for the Occasion

Patria marked the occasion with a small piece of aviation history: a Pratt & Whitney engine dating to the Second World War, recovered from a lake in Orivesi, Finland during the winter of 2025, has been conserved and put on permanent display in the lobby of the Linnavuori facility — bookending eight decades of the two companies’ shared aviation propulsion history under one roof.

FAQ: Patria F135 Engine

Does Patria build the F135 engine from scratch?

No. Patria performs final assembly of F135 engines using components supplied through the Pratt & Whitney production system, under an agreement signed in February 2026. Patria will later transition to maintenance, repair, overhaul and upgrade work for the same engines.

When do Finland’s first F-35As arrive?

Finland’s first F-35As are due to arrive at the Lapland Air Wing, based at Rovaniemi, later in 2026.

How many F-35s did Finland order?

Finland selected the F-35A in 2021 and authorized procurement of 64 Block 4 aircraft, along with associated weapons, training and sustainment arrangements.

Looking Ahead

Patria has not released a schedule for its next F135 engine completions at Linnavuori. Attention now turns to the Lapland Air Wing’s first F-35A arrivals at Rovaniemi later this year. The Aviation Diary will continue following the Patria F135 engine program and Finland’s broader F-35 industrial buildout as further milestones are announced.

Sources

Nabeel Khan

Written by

Nabeel Khan

Nabeel Khan is the founder and editor of The Aviation Diary. An aerospace industry professional and lifelong aviation enthusiast, he covers military aviation, commercial aviation, aerospace, defense, and space. He built an aviation following across Instagram, TikTok, YouTube, and Threads before launching The Aviation Diary to bring that same coverage to a dedicated news site. Views expressed are his own.

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