The newest Director, Operational Take a look at & Analysis report says no combat-capable F-35 TR-3 plane have been delivered to the U.S. army till September 2025 due to the truncated software program.
The not too long ago launched 2025 Director, Operational Take a look at & Analysis (DOT&E) annual report introduced one other replace to the lengthy saga of the F-35’s Know-how Refresh 3 (TR-3) {hardware} improve. TR-3 is the spine upon which the brand new Block 4 is predicated, permitting the introduction of latest superior capabilities on the F-35 Lightning II.
A New Catch
As we beforehand reported, TR-3 had already brought on many points for the F-35 program, together with a prolonged halt in deliveries. The halt, which lasted from July 2023 to July 2024, reportedly noticed as much as 110 plane positioned in storage earlier than the F-35 Joint Program Workplace (JPO) allowed deliveries to renew.
The backlog of the deliveries was cleared in Might 2025, though we’ve got now found a catch via the 2025 DOT&E report. These first TR-3-configured F-35s are, actually, non-combat-capable.
“No combat-capable TR-3 plane have been delivered to the U.S. Companies to this point,” says the report. “As of the top of September 2025, 158 F-35s had been delivered within the TR-3 configuration and a complete of 812 plane (any configuration) have been produced and delivered to the U.S. Companies.”
The reason for this new problem seems to be the truncated model of the software program that was developed “by disabling a few of the fight capabilities that had already been fielded on the TR-2 plane.” This was performed “in an effort to stabilize the efficiency on the brand new TR-3 {hardware}” and permit the deliveries to renew.
This doesn’t imply that the plane are unusable, however moderately they’ve a restricted set of capabilities which might limit them to testing and coaching efforts. Particularly, the wording used within the report means that these plane function the brand new capabilities launched by TR-3 and most, however not all, of the capabilities of the TR-2.
This might need been performed purportedly to permit personnel to start coaching on the brand new variant with out hampering fight readiness. In the meantime, growth and testing would proceed to resolve the remaining points, with the lacking capabilities regularly retrofitted within the TR-3 plane already delivered.
The total set of capabilities launched by TR-3 has not been disclosed for apparent causes. Nonetheless, the DOT&E report explicitly mentions the brand new software program upgrades presently being examined embrace “new Electromagnetic Warfare functionality enabled by upgraded {hardware} on TR-3 plane beginning in manufacturing lot 19.”
“The TR-3 avionics improve, which incorporates upgraded foremost mission computer systems (known as built-in core processors), plane reminiscence system, and panoramic cockpit shows, is a key enabler for brand new Block 4 mission methods capabilities,” provides the report. “The TR-3 improve replaces the corresponding TR-2 elements which are presently fielded in almost the whole fleet of F-35 plane.”
What’s the Actual Story Right here?
Whereas the DOT&E may sound alarming, you will need to observe that the one we will entry is the general public model and thus we do not need lots of the particulars which totally describe the scenario. In actual fact, these are included within the categorised report delivered to the Pentagon.
With out these particulars, an goal evaluation can’t be performed as it could simply turn into pure hypothesis. Moreover, as talked about within the report, the knowledge just isn’t updated, as figures are counted till the top of September 2025 and we do not need affirmation whether or not combat-capable TR-3 configured F-35s have been delivered after that date.
Enjoying down the TR-3-related issues as they’re attributed to software program can also be not superb, because the F-35 has lengthy been mentioned to run on over 8 million strains of code. Thus, contemplating that the F-35 is a software-defined weapon system, any modification to the software program’s code have to be engineered to make sure it doesn’t intervene with different strains, one thing that’s simpler mentioned than performed.
Even with the problems across the TR-3 program, it needs to be remembered that the F-35 is already operational and on the frontlines. The Lightning II has lengthy been utilized by the U.S. and overseas operators in actual missions, proving the maturity of the platform.
As an example, the F-35 noticed in depth use throughout this yr’s operations towards Venezuela and Iran, simply to say the newest ones. The fifth gen fighter has been working towards high-end air protection networks within the Suppression/Destruction of Enemy Air Defenses (SEAD/DEAD) position – its major mission set – in addition to different missions.
Due to its capabilities, the F-35 has been described as a vital asset within the lineup of the U.S. army. Furthermore, no F-35s have been misplaced in fight attributable to enemy motion, and the one one reportedly hit by enemy hearth was capable of safely return again for an emergency touchdown at a pleasant air base.
This brings us again to the preliminary consideration: ought to this actually be alarming? The numbers supplied by the DOT&E point out that the plane affected by the difficulty are roughly 20% of the whole U.S. fleet, with over 650 jets not affected that means that, even with a mission succesful price of roughly 50%, over 300 F-35s would all the time be prepared to be used.
Moreover, the F-35 has a world fleet of over 1,300 plane which already handed the a million flight hours milestone. This already speaks volumes concerning the platform’s maturity.
Growth and Testing Challenges
Whereas the plane within the new configuration are being delivered, the testing of the Know-how Refresh 3 continues to be in progress. That is being managed by the United Operational Take a look at Staff (UOTT), which incorporates personnel from the USA, the UK, and Australia.
“All through FY25, the F-35 growth effort continued to face challenges in delivering dependable, totally practical software program to the operational check (OT) groups,” says the DO&E report. As beforehand talked about, the steadiness and reliability of the software program have been among the many foremost points that slowed the fielding of TR-3.
“The event groups centered on two software program variations, one every for the Know-how Refresh (TR)-2 and TR-3 {hardware} configurations,” continues the report. “Regardless of the TR-3 functionality being a rehost of TR-2, the newest iteration of TR-3 software program (40R02) was unsuitable for devoted OT. Equally, the newest model of TR-2 software program (30R08) – meant to be the final model of software program fielded on the TR-2 plane – was predominantly unusable for extra OT occasions throughout most of FY25, attributable to stability issues, shortfalls in functionality, and on-going discovery of deficiencies.”
This seems to be the consequence of different issues outdoors of the software program’s growth, which decelerate the Operational Testing (OT). In flip, this slows down the invention of latest issues and their answer, rising the general time wanted to repair the problems with TR-3.
“The F-35 Joint Program Workplace (JPO) deliberate for wanted modifications to OT plane, however useful resource shortfalls haven’t enabled well timed supply of those modifications,” explains the report. “Present plane forecasts present that there won’t be sufficient OT plane accessible to perform devoted OT in consultant formations of plane.”
The wording seems to level to a scarcity of instrumented plane accessible for the testing of latest software program, moderately than longer growth timelines. As consequence of this case, the DOT&E says it “continues to have issues concerning the capability of the United Operational Take a look at Staff (UOTT) […] to conduct ample testing of the Block 4 capabilities due to the decreased variety of OT plane with the required {hardware} configurations and the required instrumentation to check mission methods and weapons integration.”
A greater thought of the scenario is later supplied with the variety of plane. “Funding and contracting delays have made it troublesome for the OT groups to have eight totally succesful plane accessible for devoted OT trials through the OT intervals,” says the report. “Given OT plane availability charges, this typically means a complete of 12 OT plane have to be deliberate and funded to make sure 8 OT plane can be found for many missions.”
The report, talking concerning the testing of the final deliberate TR-2 software program model, sheds some gentle on the kinds of open-air checks being carried out. Amongst these are:
Functionality Take a look at Occasions (CTEs), which can be carried out with early, much less mature variations of the software program, designed to characterize the efficiency of latest capabilities or confirm corrections to deficiencies recognized throughout earlier testing;
Mission Space Trials (MATs), which can even be flown with early variations of software program, are usually carried out as part of massive drive workout routines to gather knowledge from eventualities extra operationally consultant;
Devoted OT missions, that are typically flown with the ultimate model of software program, assess operational effectiveness by way of lethality and survivability in mission eventualities;
Devoted weapon employment occasions, which embrace each captive carry (the place weapon check article are flown, however not launched) and dwell hearth occasions.
Concerning the open testing of the primary TR-3 manufacturing configuration, the planning has decided which would be the preliminary software program model examined. In actual fact, two earlier variations have been designated “as not appropriate for conducting OT” by the JPO.
The report thus mentions that the event testing of the TR-3 plane and related software program “remained considerably not on time all through FY25.” A timeline has not been talked about as quite a lot of situation have to be met first.
“Plane modifications, flight check instrumentation, OABS capabilities, and steady software program will all be required earlier than devoted OT can start on TR-3 plane,” explains the report. “Moreover, program funding constraints will make it troublesome to plan for and achieve ample weapons testing.”
As it may be famous, the DOT&E report places emphasis on the steadiness of the software program. This isn’t informal, as defined later within the doc: “F-35 plane mission methods instabilities can degrade mission efficiency and should require a pilot-initiated reset of mission methods in-flight, which may have extreme penalties throughout fight.”
Radar-less F-35s
The newest DOT&E report’s description of the issues associated to the F-35’s TR-3 improve arrives virtually similtaneously the newest stories concerning the fighter being delivered with out a radar. We initially reported about this problem in February 2026 right here at The Aviationist.
On the time, the difficulty was mentioned to contain F-35s delivered to the U.S. army since June 2025, based on Protection Each day and affiliate publication Avionics Worldwide, who first printed the stories quoting an unnamed supply. In an emailed assertion, an F-35 JPO spokesperson instructed us that F-35s are being constructed to accommodate the brand new APG-85 radar and a few started deliveries in 2025, however they may not present extra data.
Rep. Rob Wittman (R-Va.), Vice Chairman of the Home Armed Companies Committee and Chairman of the Tactical Air and Land Forces Subcommittee, equally mentioned he couldn’t remark. Nonetheless, he commented concerning the integration of the brand new radar, which he outlined as “difficult.”
“The APG-81 is totally different than the APG-85, and subsequently delivering the plane, as presently configured, with an APG-85 radar versus an APG-81 radar is difficult,” mentioned Wittman. “The bulkhead configuration is vital as a result of for each of the radars, they’re very totally different.”
“It’s an extremely superior radar,” Wittman additional added. “The arrays on it give it rather more energy which is why we’ve got to improve the engine. I feel we want about 82 kilowatts of energy versus what it’s producing proper now. The APG-85 is vital to Block 4, and it’s key to TR-3 software program improve capabilities and integration with the imaging system, the Distributed Aperture System.”
Final week, Wittman was interviewed by Breaking Protection, offering an replace concerning the problem and revealing that the preliminary stories have been partially right. In actual fact, he confirmed that F-35s for the U.S. army might be delivered with out the brand new radar beginning this fall.
It isn’t but clear what number of plane can be affected. Nonetheless, as we beforehand reported, even with out the radar, the plane would nonetheless be airworthy, though they might require a ballast within the nostril to keep away from affecting the stability whereas in flight.
“We even have a difficulty with the brand new radars, the APG-85 radars, and ensuring that they’re on the brand new plane,” mentioned Wittman to Breaking Protection. “Proper now, they’re going to be produced with ballasts, which too, creates an plane that’s not going to be combat-coded anytime quickly.”
The difficulty is among the particulars confirmed from the preliminary reporting, the bulkhead. In actual fact, Breaking Protection confirmed that the totally different dimension of the APG-85 radar required a distinct bulkhead, which prevents the set up of the present APG-81 radar.
One of many causes is expounded to the truth that the bulkhead can also be used to appropriately place the radar so the array may be within the right angle. Having to make use of a distinct angle would tremendously have an effect on the efficiency of the radar.
The F-35’s Function in Operation Epic Fury
There was a number of debate on-line concerning the employment of F-35s, each American and Israeli, within the ongoing air marketing campaign towards Iran. Pictures of the Lightnings and Adirs (because the Israeli variant is known as) commonly shared on-line by the U.S. Central Command and the Israeli Protection Forces have bolstered the “on-line fame” of the considerably controversial plane, an aura boosted even additional by the primary confirmed air-to-air kill scored by an Israeli F-35I, which downed an Iranian Yak-130, in addition to by the shocking survival of a U.S. F-35 that was capable of land safely after being hit by an Iranian surface-to-air missile.
Whereas the F-35 is actually enjoying an necessary position within the air marketing campaign, showcasing its capability to function in contested airspace, launching from land and sea as no different tactical jet is presently capable of do, it’s most likely too early to attract too many conclusions. That capability has by no means actually been doubtful, so the lively participation of the fifth-generation plane within the strikes isn’t a surprise in any respect. What must be assessed, and is not possible to evaluate proper now, is the sortie price, mission-capable price, turnaround time, and abort price. A severe evaluation of the F-35’s contribution to the air warfare in Iran additionally must bear in mind weapons expended per goal, gasoline and logistics burden, upkeep hours per flight hour, tanker demand, and value per efficient sortie. Some weapon methods could seem extremely efficient within the preliminary phases of an air marketing campaign however turn into much less efficient if upkeep, munitions, basing, or attrition turn into limiting elements.
We are able to additionally assume that the presence of the F-35s, as with different high-profile weapons methods or plane, has most likely had a coercive impact on Iranian techniques: it could have compelled radars to close down, plane to stay grounded, forces to disperse, belongings to be moved, or operational tempo to be decreased. Generally coercive impact issues as a lot as kinetic impact.
The subject is rather more difficult than some may consider. Whereas the F-35’s contribution may also be measured by targets struck, weapons employed, and comparable metrics, there are different, much less measurable contributions that must be thought of to realize a extra full image. As we’ve got defined for a few years right here at The Aviationist, the Lightning II is hardly “simply” a multirole (or “omnirole” one as somebody name it) plane: it’s a flying sensor that may present improved situational consciousness to the broader drive, enabling older-generation plane to function extra successfully. Solely time will inform.
