New F-35 Block 4 stealth technology is already a year behind

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Imagine the world’s most advanced stealth fighters, the F-35s, in a state of suspense as the Pentagon holds off on accepting any new jets. The reason? They’re waiting for the completion of testing on upgraded technology that will be installed on these cutting-edge machines. 

Photo credit: Il Manifesto

According to Russ Goemaere, a spokesperson for the F-35 Joint Program Office, the halt on new F-35 deliveries could last anywhere from December to as late as next April. This unexpected pause has left Lockheed Martin, the company contracted to deliver these jets, in a bit of a pickle. 

Under the terms of its contract, Lockheed Martin is committed to delivering nine planes per month, each equipped with the new tech upgrade. If the delay extends to December, the company will be left with 45 jets in its inventory. The number could rise to a staggering 81 if the delay continues until April. 

The project at the heart of this delay is Block 4, an ambitious effort by the Pentagon to update several technologies in its fleet of F-35s. But before these jets can receive the Block 4 upgrades, they need a set of hardware and software improvements, collectively known as Technology Refresh 3, or TR-3. Unfortunately, TR-3 is already trailing a year behind its initial schedule.   

Photo credit: Aviation Week

Goemaere, in his statement to Defense One, confirmed that starting from August, around nine TR-3 aircraft per month are slated for delivery. “Starting later this summer, F-35 aircraft coming off the production line with TR-3 hardware will not be accepted until the relevant combat capability is validated by our users’ expectations. The JPO and Lockheed Martin will ensure these aircraft are safely and securely stored until acceptance occurs,” he assured.  

The news that the Pentagon will not accept new F-35s until testing is completed was first reported by Breaking Defense. Meanwhile, despite the potential delay, Lockheed Martin remains optimistic, stating they still plan to fulfill their delivery commitment by December. 

“Every test program comes with its own set of challenges as risk analysis models predict. Despite the Joint Program Office [JPO] acknowledging a potential delivery window between December 2023 and April 2024, they remain steadfast in their commitment to deliver the first TR-3 jet in 2023,” the company stated. 

Photo credit: IAF

When probed about the possible financial implications of the delay, Lockheed refrained from commenting, citing the imminent announcement of their second-quarter earnings next month. 

The postponement of TR-3 deliveries translates into the reduced capacity for the Air Force in the immediate future, according to Doug Birkey, Executive Director of the Mitchell Institute for Aerospace Studies. He shared this insight with reporters on Wednesday, before the unveiling of a fresh report on 5th-generation airpower. Birkey pointed out that the Air Combat Command is meticulously managing resources to prevent a capacity gap. 

Despite the delay, Lockheed Martin continues to produce jets, accumulating a stockpile at Fort Worth, Texas. Birkey believes that once the software issues are resolved, the capacity will be quickly reinstated. His advice to Lockheed Martin is to maintain production momentum, allocate the necessary funds, and focus on resolving the issues at hand. 

The first TR-3 flight test, conducted in January, unearthed software problems that were overlooked during lab tests, as per a recent Government Accountability Office [GAO] report. This has put pressure on the project, which now has a tighter timeline to complete additional tests and fix these software problems. The GAO report also highlighted escalating costs for Block 4 upgrades, with a $1.4 billion increase since their April 2022 report, taking the total to a staggering $16.5 billion. 

However, Birkey asserted that the blame for the F-35 delays and cost overruns doesn’t lie solely with the industrial sector. He attributed the situation to a combination of factors, including the structure of the JPO and the design of the program. Despite these challenges, Birkey remains optimistic about the Block 4 upgrades, insisting that it’s the Pentagon’s best shot at restoring the program’s health. He believes that the Combatant commands need solutions, and Block 4 could deliver just that. 

Photo credit: USAF

He believes that TR-3/ Block 4 will be fundamentally superior, likening it to a brand-new jet in many aspects. TR-3, which forms the IT backbone of the Block 4 upgrades, will incorporate a new integrated core processor essential for future sensors and weapons, according to Greg Ulmer, Executive Vice President of Lockheed’s Aeronautics business. He shared this information last week at the Paris Air Show. 

Ulmer revealed that flight testing for the new configuration is currently underway at Edwards Air Force Base and Naval Air Station Patuxent River. He added, “You’ll see us complete that flight test, we’ll get the certifications underwritten, certified by the government, and then you’ll see us resume delivery.”


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