Lockheed Martin's F-35 multirole stealth fighter jet's Block 4 upgrades are plagued by 65 basic deficiencies, failing to meet basic testing specifications, the Office of the Director of Operational Tests and Evaluation (DOT&E) said in a report.

The aircraft completed the readiness review for the Joint Simulation Environment (JSE) trials in September 2023 and was certified for testing despite the 65 performance scores, which were marked below JSE requirements, RIA Novosti reported.

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 Technology Refresh 3 (TR-3) hardware, which will be installed into Lot 15 production aircraft.

TR-3 upgrades backfire

The JPO seeks to allow the F-35 to carry more weapons, better recognize targets, and improve its electronic warfare capabilities, among several other features, via TR-3 upgrades.

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

Deliveries of Lot 15 aircraft with the TR-3 configuration, which underwent testing, have been put on hold "until more testing can be completed and the avionics issues resolved."

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.

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Block 4 program to cost 60% more than planned

A recent report released by the Government Accountability Office (GAO) showed that the Lockheed Martin F-35 Joint Strike Fighter program, after 18 years of development and deployment, is grappling with soaring costs, unforeseen delays, and technical complications.

Most importantly, the $10 billion Block 4 program, designed to counter challenges from major peer competitor countries such as Russia and China, faces further setbacks. The GAO warned that the program will now cost 60% more than its original hefty price tag.

The GAO's report revealed that the costs of the F-35 program have skyrocketed by at least $44 billion, further exacerbating concerns about its financial sustainability. Top officials overseeing the project confirmed to Congress that new delays continue to emerge, with no immediate resolution in sight.

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