F-35 Modernization Brings Samarium Sourcing Into Focus Ahead of 2027
Military & DefenseOct 3, 2026
China | United States
Rare-earth permanent magnets are used across modern combat aircraft wherever compact, high-performance electric motors, actuators and power-management equipment must operate reliably under demanding thermal and mechanical conditions. On the F-35, that makes magnet sourcing relevant to supporting systems including actuation, thermal management and electrical equipment rather than simply to the jet's F135 propulsion engine. Samarium-cobalt magnets are particularly important in aerospace and defense applications because they retain magnetic performance at high temperatures. The precise rare-earth content of an individual F-35 is not publicly established in the sources used here, so the supply-chain issue is better understood through the components and procurement rules that govern covered magnets. 24
Honeywell's latest F-35 cooling roadmap puts those supporting systems back in the spotlight as U.S. defense procurement rules prepare to reach further upstream into magnet supply chains. The two developments raise separate questions: how to support increasingly demanding aircraft electronics, and how to establish compliant origins for covered materials. 14
In a September 14, 2026 update, Honeywell described a path from the Power and Thermal Management System's current 32 kilowatts of cooling to 40 kilowatts targeted for 2029, with a longer-term pathway to 80 kilowatts. The company explicitly distinguishes increased cooling from increased electrical generation: its proposed upgrade expands thermal capacity, not the PTMS's power-generation capability. These figures describe the supplier's roadmap, rather than a newly announced government procurement award. 1
The PTMS combines auxiliary and emergency power with environmental control and thermal management. Honeywell says the F-35 installation supports main-engine starting and manages aircraft heat loads. That makes it part of the infrastructure supporting the jet's mission systems, rather than the aircraft's main propulsion engine itself. 2
Material compliance has already mattered to this equipment. On October 8, 2022, the Pentagon announced a national-security waiver allowing acceptance of F-35 aircraft with non-compliant specialty metals in Honeywell Integrated Power Package turbomachines. The determination covered 126 aircraft under the Lot 12-14 production contract. That historical waiver illustrates how a component's material origin can affect aircraft acceptance; it is not evidence of a fresh 2026 delivery stoppage. 3
The next sourcing milestone is January 1, 2027. Under DFARS 225.7018-2, applicable restrictions on samarium-cobalt magnets broaden from alloy melting and subsequent magnet production to the full chain, including mining or production of cobalt and samarium feedstock through finished magnets. Refining and separation also fall within the expanded general restriction. For covered procurements, changing the location of final magnet manufacture alone therefore cannot establish compliance if restricted upstream processing remains. 4
The rules retain specified exceptions and nonavailability procedures. DFARS 225.7018-3 addresses circumstances including certain smaller acquisitions and situations where compliant material of satisfactory quality, quantity and required form cannot be obtained when needed at a reasonable price. Applicability depends on the acquisition and relevant provisions; January 2027 is a procurement sourcing milestone, not an automatic grounding date for aircraft already in service. 5
Recent funding shows where part of the alternative supply chain is being developed. Ucore said on September 14 that an additional US$4.6 million agreement modification would support samarium and gadolinium process development in Kingston, Canada, and deployment of its Enhanced Machine A at the planned Louisiana Strategic Metals Complex in Alexandria. The company put total funding under its agreement at US$27 million. Samarium-cobalt magnets serve demanding aerospace and defense applications where performance at high temperatures matters. 6
That award targets separation, one stage between raw feedstock and finished industrial materials. Ucore's announcement does not establish an F-35 supply contract or completed, qualified magnet production. Our assessment is that the important milestones now lie between funding and delivery: demonstrated separation performance, traceable feedstock and downstream customer qualification. Honeywell's cooling targets and Ucore's processing work should be tracked on their own timelines, without assuming that a cooling upgrade necessarily increases samarium demand. 16
Honeywell's latest F-35 cooling roadmap puts those supporting systems back in the spotlight as U.S. defense procurement rules prepare to reach further upstream into magnet supply chains. The two developments raise separate questions: how to support increasingly demanding aircraft electronics, and how to establish compliant origins for covered materials. 14
In a September 14, 2026 update, Honeywell described a path from the Power and Thermal Management System's current 32 kilowatts of cooling to 40 kilowatts targeted for 2029, with a longer-term pathway to 80 kilowatts. The company explicitly distinguishes increased cooling from increased electrical generation: its proposed upgrade expands thermal capacity, not the PTMS's power-generation capability. These figures describe the supplier's roadmap, rather than a newly announced government procurement award. 1
The PTMS combines auxiliary and emergency power with environmental control and thermal management. Honeywell says the F-35 installation supports main-engine starting and manages aircraft heat loads. That makes it part of the infrastructure supporting the jet's mission systems, rather than the aircraft's main propulsion engine itself. 2
Material compliance has already mattered to this equipment. On October 8, 2022, the Pentagon announced a national-security waiver allowing acceptance of F-35 aircraft with non-compliant specialty metals in Honeywell Integrated Power Package turbomachines. The determination covered 126 aircraft under the Lot 12-14 production contract. That historical waiver illustrates how a component's material origin can affect aircraft acceptance; it is not evidence of a fresh 2026 delivery stoppage. 3
The next sourcing milestone is January 1, 2027. Under DFARS 225.7018-2, applicable restrictions on samarium-cobalt magnets broaden from alloy melting and subsequent magnet production to the full chain, including mining or production of cobalt and samarium feedstock through finished magnets. Refining and separation also fall within the expanded general restriction. For covered procurements, changing the location of final magnet manufacture alone therefore cannot establish compliance if restricted upstream processing remains. 4
The rules retain specified exceptions and nonavailability procedures. DFARS 225.7018-3 addresses circumstances including certain smaller acquisitions and situations where compliant material of satisfactory quality, quantity and required form cannot be obtained when needed at a reasonable price. Applicability depends on the acquisition and relevant provisions; January 2027 is a procurement sourcing milestone, not an automatic grounding date for aircraft already in service. 5
Recent funding shows where part of the alternative supply chain is being developed. Ucore said on September 14 that an additional US$4.6 million agreement modification would support samarium and gadolinium process development in Kingston, Canada, and deployment of its Enhanced Machine A at the planned Louisiana Strategic Metals Complex in Alexandria. The company put total funding under its agreement at US$27 million. Samarium-cobalt magnets serve demanding aerospace and defense applications where performance at high temperatures matters. 6
That award targets separation, one stage between raw feedstock and finished industrial materials. Ucore's announcement does not establish an F-35 supply contract or completed, qualified magnet production. Our assessment is that the important milestones now lie between funding and delivery: demonstrated separation performance, traceable feedstock and downstream customer qualification. Honeywell's cooling targets and Ucore's processing work should be tracked on their own timelines, without assuming that a cooling upgrade necessarily increases samarium demand. 16