F-35A Training

Two U.S. Air Force F-35A Lightning IIs, assigned to the 4th Fighter Squadron from Hill Air Force Base, Utah, fly over the base and the surrounding area on Feb 14, 2018. (US Air Force/Andrew Lee)

WASHINGTON — The Pentagon has approved a national security waiver that will allow Lockheed Martin to resume F-35 deliveries, which have been on hold since August due to concerns about Chinese alloys found in a component.

A copy of the waiver — signed by Bill LaPlante, the undersecretary of defense for acquisition and sustainment — was sent to Capitol Hill today, two sources told Breaking Defense on background, confirming a report by Politico.

The Defense Department halted F-35 deliveries on Aug. 31, after Honeywell — the maker of the F-35’s turbomachine, which helps provide the power needed to start the engine — disclosed that a supplier for the turbomachine’s lube pumps had used magnets containing cobalt and samarium alloys from China.

The waiver “will enable the acceptance of 126 F-35 aircraft containing non-compliant specialty materials,” LaPlante wrote in a Oct. 7 letter sent to the congressional defense committees. “The waiver will apply to nine Lot 13 and 117 Lot 14 F-35 aircraft in production or awaiting delivery. The final Lot 14 aircraft is projected for delivery on Oct. 31, 2023.”

The F-35 program office has assessed that the alloys do not pose a safety or security risk, and flight operations of already-delivered F-35s have been ongoing throughout the pause. LaPlante noted in his letter that previously delivered aircraft have “over 500,000 flight hours with no failures attributed to the high performance magnets containing the specialty metal.”

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Instead, the department’s major concern has been whether this specific use of Chinese materials was a violation of the Defense Federal Acquisition Regulations Supplement (DFARS), the Pentagon’s overarching set of rules for procurement.

Lockheed and Honeywell have identified a new US-based supplier for the alloys, which will begin deliveries this month, Lockheed has previously stated. However, it will take time for the magnets made from the new alloys to work their way from the lube pump supplier to the finished F-35s rolling off Lockheed’s production line, with the first F-35 with compliant magnets delivering in Lot 15, according to LaPlante’s letter.

“The department is assessing whether a waiver is necessary for already delivered and accepted aircraft,” which number 841 jets, LaPlante wrote.

Although the F-35 deliveries have been suspended for more than a month, production has kept going at Lockheed’s mile-line facility in Fort Worth, Texas and among its suppliers, Greg Ulmer, head of Lockheed’s aeronautics business, told Breaking Defense during a Sept. 19 interview at the Air and Space Forces conference.

“The workflow within the F-35 system is unchanged all the way through flying and accepting the aircraft, we’re just not delivering the aircraft,” he said. “So if you were in Fort Worth today, you would see airplanes launching and recovering.”

By that point in time, Lockheed had submitted the documentation for a waiver, but had not completed an investigation into how the supplier made the mistake of sourcing Chinese material for the nation’s most advanced stealth fighter.

Lockheed’s contract with the US government stipulates DFARS requirements that are passed from Lockheed to its second-tier suppliers, then from those subcontractors to third-tier suppliers, and so forth for the 1,900 companies within the F-35’s supply chain, Ulmer said.

“We get what we call a ‘certificate of conformance’ back to us from those suppliers. … We do due diligence relative to looking at those certificates of compliance and validating whether or not they’re true,” he said. The company is trying to understand “where did that process break down? … We’re working with the government hand-in-hand to go do that assessment. And then we’re taking that also to double down across the supply chain, relative to this specific DFARS requirement.”