The Government Accountability Office (GAO) reported on Thursday that ongoing issues with both the hardware and software of the F-35 Joint Strike Fighter's Technology Refresh 3 (TR-3) upgrade program have resulted in delays, pushing back the delivery of the new system and its installation in existing aircraft until next year.

"The F-35 program is facing a range of issues due to the late deliveries of TR-3 hardware and software," the report said. "These challenges, collectively, will delay the full delivery of TR-3 with new capabilities until 2025."

According to the report, citing Lockheed Martin, the supplier responsible for producing the integrated core processor is delivering this component late and with quality issues.

Concerning software, challenges with aircraft software supporting radar and electronic warfare systems "have been especially prevalent, with some test pilots reporting that they had to reboot their entire radar and electronic warfare systems mid-flight to get them back online."

Consequently, the report states that TR-3 software with enhanced capabilities will not be delivered until 2025, which is two years later than the initial schedule.

New GAO report dropped about the F-35 program (short🧵)

1/ Besides the known software issues, supply chain issues are also contributing to the TR-3 delays (hardware wise).

2/ The deliveries of TR-3 equipped “combat training-capable” aircraft are expected to start next month pic.twitter.com/PIrIzytlxF

— Doha (@Doha104p3) May 16, 2024

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Similar issues were reported earlier this year about a separate upgrade initiative for the F-35, with the Office of the Director of Operational Tests and Evaluation (DOT&E) reporting that the Block 4 upgrade program was experiencing a wide range of issues. 

Among the issues that the F-35 Lightning II Joint Program Office (JPO) continues to face are immature and deficient Block 4 mission systems software, as well as avionics stability problems with the new TR-3 hardware, which were announced to be installed into Lot 15 production aircraft.

In December 2022, an agreement between the F-35 JPO and Lockheed Martin was finalized for the production and delivery of 398 F-35s, costing $30 billion, in Lots 15 and 16, with an option for Lot 17.

At the time, deliveries of Lot 15 aircraft with the TR-3 configuration have been put on hold until further testing and resolution of avionics issues.

It is worth noting that, according to the contract signed between the JPO and Lockheed Martic, Lot 15 includes 145 aircraft.

"As a result, deliveries of production Lot 15 aircraft in the TR-3 configuration are on hold until more testing can be completed and the avionics issues resolved. ...[T]hese delays prevented the F-35 JPO from adequately planning and programming for hardware modifications ... of the upgraded hardware configuration," the report said.

Moreover, the necessary flight test instrumentation, including both aircraft and open-air battle shaping instrumentation, for both, the remaining TR-2 configuration and upgraded TR-3 aircraft, are not all on contract and will not be available in time, the report added.