F-35 May Never Be Ready for Combat

Testing Report Contradicts Air Force Leadership’s Rosy Pronouncements
The F-35 in an airplane hangar

The F-35 Joint Strike Fighter program is the most expensive procurement program in Pentagon history. It’s been plagued by schedule delays, gross cost overruns, and a slew of underwhelming performance reviews. Last month the Air Force declared its variant “ready for combat,” and most press reports lauded this as a signal that the program had turned a corner. But a memo issued from the Pentagon’s top testing official, based largely upon the Air Force’s own test data, showed that the Air Force’s declaration was wildly premature.

Dr. Michael Gilmore’s latest memorandum is damning. The F-35 program has derailed to the point where it “is actually not on a path toward success, but instead on a path toward failing to deliver the full Block 3F capabilities for which the Department is paying almost $400 billion.” The 16-page memo, first reported by Tony Capaccio at Bloomberg and then by others, details just how troubled this program is: years behind schedule and failing to deliver even the most basic capabilities taxpayers, and the men and women who will entrust their lives to it, have been told to expect.

The Pentagon’s top testing office warns that the F-35 is in no way ready for combat since it is “not effective and not suitable across the required mission areas and against currently fielded threats.” (Emphasis added) As it stands now, the F-35 would need to run away from combat and have other planes come to its rescue, since it “will need support to locate and avoid modern threats, acquire targets, and engage formations of enemy fighter aircraft due to outstanding performance deficiencies and limited weapons carriage available (i.e., two bombs and two air-to-air missiles).” In several instances, the memo rated the F-35A less capable than the aircraft we already have.

The memo from the Director, Operational Test & Evaluation makes very clear that the constant stream of positive pronouncements made by the Joint Program Office and Air Force generals have been false. Statements that General Hawk Carlisle, the Air Force’s Air Combat Commander, recently made to the press and that Joint Program Office chief Lt. Gen. Christopher Bogdan has made in testimony on Capitol Hill are directly contradicted by the facts reported in the memorandum. “The F-35A will be the most dominant aircraft in our inventory because it can go where our legacy aircraft cannot and provide the capabilities our commanders need on the modern battlefield,” General Carlisle said during the IOC announcement. According to Dr. Gilmore, however, this is not the case and there is evidence that the Air Force knew this already. Before declaring its variant ready for combat the Air Force conducted and presumably read its own evaluation. The DOT&E memo clearly states that the findings contained within are “fully consistent” with the official report of the Air Force’s own internal IOC Readiness Assessment Team report.

This memo is a brutally revealing assessment of the F-35’s performance deficiencies. It’s important to note that Congress and the public know of these severe and debilitating deficiencies only because Congress mandated an independent testing office with broad bipartisan support in 1983—and because the present director is a person of independence and integrity.

Limited Combat Ability

The Air Force stated to Congress that its Initial Operational Capability (“combat ready”) declaration would be based on the ability of the current F-35A (Block 3i) to perform three basic missions: close air support, interdiction, and limited attacks on enemy air defenses.

The services are taking delivery of new F-35s in succeeding “block” versions, each adding increments to the previous block’s incomplete combat capabilities. The version equipping the Air Force’s IOC squadron, the Block 3i, is an interim version in which the earlier Block 2B’s obsolete computer has been replaced with a new one. Meanwhile, schedule slippage continues on the F-35 program’s Block 3F development effort, intended to incorporate all the contractually mandated combat capabilities.

The Air Force’s current configuration can only carry two long range air-to-air missiles (but no dogfighting short-range heat-seeking missiles) and two bombs to attack targets on the ground. This very limited weapons load-out is the result of ongoing software deficiencies, not of any potential (though untested) ability of the plane to carry more types of weapons. Larger numbers of weapons would have to be carried externally, however, which compromises the aircraft’s range and stealth.

The next software version, Block 3F which is currently suffering major development problems, should eventually allow the F-35 to employ the larger variety of weapons originally specified in 2001, but these planes are still years away from being operationally tested, much less actually reaching the fleet. So for the time being, even if the current F-35 could perform in combat (which DOT&E’s memorandum makes clear it can’t), the small and non-diverse ammo load means any fight the F-35 finds itself in had better be a short one.

Graphic image of the front end of the F-35.
The F-35’s cannon door causes the plane to pull to one side, reducing the accuracy of the gun. (Photo by

Another of the F-35’s basic shortcomings is the lack of a usable cannon. The Block 3i aircraft lacks the ability to employ the cannon because the software needed for it is a Block 3F development and has yet to be completed. This issue has been reported many times before. Now we learn that there are doubts that the most recent version of the plane’s complicated helmet, which is the only way to aim the cannon, will be accurate enough to reliably hit air-to-air or ground targets.

This latest DOT&E report also makes public another problem with the cannon on the Air Force’s variant of the plane, the F-35A. This is the only variant that includes an internal cannon. The variants for the Marine Corps and Navy both use an external belly-mounted gun pod. In order to keep the F-35A stealthy, the internal cannon sits behind a small door that opens when the cannon is fired. The Air Force proudly released a video of the first time an F-35A test fired its cannon in flight. Now we know that the simple action of opening the small door causes the plane to turn slightly because of the door’s drag, possibly enough to cause the cannon to miss. The DOT&E memo reports that these door-induced aiming errors “exceed accuracy specifications” which will make it quite difficult for pilots to hit targets. And since the Air Force’s F-35 only holds 181 rounds—as opposed to 511 for the F-16 and 1,100 for the A-10—every bullet will count.

F-35 Close Air Support Threatens Troops on the Ground

As the debate continues about the future of the close air support mission, one thing is certain: the F-35 simply is not ready to support ground troops, and there are plenty of reasons to doubt it ever will be.

This latest DOT&E memorandum undermines one of the fundamental arguments in favor of the F-35 in the CAS role: that the F-35 will need to provide close air support in places with high levels of enemy air defenses, a mission that would require stealth capabilities. But the battles in which CAS is needed don’t generally take place in areas where there are high levels of enemy air defenses. The memo points out that close air support is normally conducted in low-air defense threat environments. This is a simple acknowledgement of the “close” in close air support. When close air support is discussed, it is important to consider the entire military system, both air and ground forces. These forces support each other mutually. By the time the ground troops who engage the enemy in close combat get involved, our military has already cleared out the heavy air defense. And the enemy ground troops will not be dragging around bulky, lightly armored, slow-to-move, hard-to-resupply “high threat” missile systems into the battle area because they will be too busy maneuvering and dodging bullets in the ground fight.

Photo of ground combat training.
U.S. Marine Corps M1A1 Abram Tanks assigned to Delta Company, 1st Tanks Battalion, 1st Marine Division, conduct the Tank Mechanized Assault Course during Integrated Training Exercise (ITX) 2-15 at the Delta Prospect Training Area aboard Camp Wilson, Marine Corps Air Ground Combat Center Twentynine Palms, California, February 1, 2015. (Photo by

Beyond that, the F-35’s ability to perform any CAS right now is extremely limited. As the DOT&E memorandum says clearly, “The F-35A in the Block 3i configuration has numerous limitations which make it less effective overall at CAS than most currently-fielded fighter aircraft like the F-15E, F-16, F-18 and A-10.” As mentioned earlier, the F-35A, now declared “Initially Operationally Capable,” can only carry two bombs, both of which are too big to be safely used near friendly troops. And even if these bombs could be used in CAS, the plane has to immediately fly back to its base to re-load after only one pass over an enemy formation. For F-35As that base is likely to be far from the battlefield since the plane needs an 8,000 foot concrete runway with a massive logistical footprint, thus seriously slowing CAS response times.

Air support for friendly troops fighting the enemy is exactly where the lack of a usable cannon is most distinctly felt—and the F-35 won’t have a usable and test-proven cannon until 2019 at best. Cannons are the most effective weapon in far more CAS situations than rockets (which the F-35A currently does not carry) or a couple of guided bombs (which it does). This is true especially when the plane needs to engage a target in a “danger close” situation, with the enemy in very close proximity to friendly troops. A GBU-12, the smaller of the two bombs the F-35A can currently employ, is a 500-pound bomb. At 250 meters (820 feet), a 500-pound bomb has a 10 percent chance of incapacitating a friendly soldier based on the military’s risk-estimate table. That might not seem like much, but history has proven that most firefights actually take place at considerably less than 100 meters. If F-35As are the aircraft providing CAS, this means that enemies closing with our troops will have plenty of room—150 meters or more—to maneuver free of fire from above.

An effective cannon on the plane closes that gap. The F-35 is supposed to eventually use a 25-millimeter cannon. The risk-estimate factor for that weapon is 100 meters. Of course the safe distance depends on how accurate the aircraft platform and aiming system is. As noted in the DOT&E memo, the simple act of opening the cannon door on the Air Force’s variant pulls the plane to one side—which could shift the bullet impacts either closer towards friendly troops or away from the enemy’s (thereby rendering the attack dangerous or useless).

The F-35 relies heavily on aerial refueling.
The F-35 relies heavily on aerial refueling. (Photo by

But that presupposes the F-35 will actually be able to stay over the battlefield long enough to be on hand to drop its bombs or fire its cannon exactly when needed. The F-35 is a notorious gas-guzzler that relies heavily on aerial tankers to stay on station for any length of time to be useful for the ground troops. According to the memorandum, “the F-35 has high fuel burn rates and slow air refueling rates that extend air refueling times and decreases overall on-station time.” Unfortunately, the troops on the ground can’t call a time-out when their air support has to leave the battle to re-fuel or reload.

The high fuel burn rate and high drag of the F-35 creates a plane that has “short legs” and inadequate on-station times. All variants and versions of the F-35 share this problem. Current short-legged fighters mitigate this deficiency by rotating flights of planes back to the tanker while another remains over the battlefield. But with the well-documented problems the services’ maintainers have keeping the F-35 flightworthy, it is doubtful there will be enough flyable planes to make such a rotation practical any time soon. Actual current F-35 sortie rates reveal the severity of the problem: today’s F-35s are flying one sortie every 5 days. In other words, a squadron deployment of 12 F-35s to Afghanistan or Syria—such as is typical for F-16s or A-10s—would only be able to put up slightly more than one two-ship mission a day to cover the whole country.

Data Fusion Causes Pilots to See Double

Publicists and “experts” sent out to try to convince the American people their money isn’t being wasted on the F-35 frequently tout the system’s capability to combine data derived from onboard sensors, sensors on other aircraft, and ground sensors. This is called sensor fusion. Each F-35, like other current fighters, has radars, video cameras, infrared seekers, and passive electronic warfare receivers to locate targets and threats in the air or on the ground. One of the main selling points for the F-35 has been that its computer system is intended to merge the information from all these onboard and offboard sensors to create a simple combined-sensor display (instead of the current approach of a separate display for every sensor) of each target and each threat for the pilot. This single display is shared instantly with every other plane in the formation. This is supposed to provide everyone with a more accurate, less confusing picture of the target and threat environment surrounding the formation—and to do so quickly without the need for time-consuming radio voice exchanges.

That’s what it’s supposed to do anyway. As it turns out, the F-35s have difficulty managing and fusing their own data, let alone that of their wingmen or surveillance assets further away.

Test pilots have reported their F-35s are creating false multiple tracks when all of their sensors are turned on. For example, when a radar and an infrared sensor detects the same enemy plane, the two sensors display it on the helmet-mounted sight as two enemy planes. The same thing happens when two or more sensors detect the same ground target.

Test pilots have worked around this problem by turning off all but one of their sensors to eliminate the multiple tracks. DOT&E says this is “unacceptable for combat and violates the basic principle of fusing contributions from multiple sensors into an accurate track and clear display to gain situational awareness and to identify and engage enemy tracks.”

It is bad enough that each individual F-35 computer struggles to create a clear picture of what is going on in the battlespace for the pilot. But the false target problem is compounded when multiple F-35s try to share data through what is called the Multi-Aircraft Data Link.

What has been described as one of the F-35’s greatest advantages has yet to live up to expectations—and, to the contrary, has been increasing the pilot’s workload.

Logistics Software Falling Behind

Another major and expensive component of the F-35 program, the Autonomic Logistics Information System (ALIS), is a massive computer system intended to automate mission operations, maintenance diagnosis, maintenance scheduling, and parts ordering. But the cumbersome ALIS continues to be a major headache for the program. An updated version, ALIS 2.0.2, was supposed to be delivered in time for the Air Force’s Initial Operational Capability announcement. Yet IOC was declared without the new version, which remains seriously delayed because Lockheed has been unable to integrate Pratt and Whitney’s separate engine computer data system into ALIS.

Photo of F-35 maintenance.
Uploading data into Autonomic Logistics Information System can take up to 24 hours. (Photo by

ALIS combines aircraft onboard and ground-based computers and software to create a world-wide network that, for each F-35 flight, uploads and downloads flight path/target/threat data (at beyond top secret level), diagnoses maintenance problems, assigns corrective maintenance actions to mechanics, orders parts, tracks their installation, tracks aircraft modifications, and orders mechanics to perform preventative maintenance actions. It is a massively complex system, with 24 million lines of computer code. It also requires a large, heavy footprint of hardware wherever the F-35 is based. The latest hardware version is smaller than the original bulky and undeployable ALIS units, but it still takes several days to set up whenever it is moved. This impedes the F-35’s ability to deploy quickly and raises questions about the entire program’s operational suitability.

For example, when it is working, it takes 24 hours to upload data from each plane into a new ALIS ground computer. So when an F-35 deploys to a new base, an entire day is lost as the data is passed to the new ALIS. And only one plane at a time can upload. So if the 12 F-35’s of Hill Air Force Base’s first “operational” squadron deploy to combat, it will take nearly two weeks to start maintaining the full squadron with ALIS.

Because ALIS uploads and downloads top secret mission data, the ALIS computers have to be housed in a secure compound called a Special Access Program Facility, made up of one or more modified large shipping containers called Deployable Debrief Facilities.

Furthermore, forward-deploying units not only need to lug bulky equipment and facilities to foreign battlefields, they also need to drag around civilian contractors to help set up and operate the equipment. Contractors from Lockheed Martin are essential to transfer data from the plane’s home station to the deployed ALIS unit. Field service representatives from Pratt and Whitney are also needed to download engine data for the post-flight maintenance process. This is fine during development, but in combat, such arrangements hamper rapid deployment and limit basing options to locations safe for civilians. That means basing farther from combat zones, slower emergency response times, and increased reliance on scarce aerial tankers.

Future Development in Jeopardy

The program is supposed to have truly combat-capable F-35s—Block 3F—ready for operational testing at the end of the System Development and Demonstration process, which is now scheduled to be at the end of 2018. Dr. Gilmore reports that while some progress is being made in the simpler developmental flight-testing process, the pace has fallen far behind that which is necessary to complete the Block 3F testing within the remaining schedule and budget. And this is the point in the developmental flight test plan where the most complex capabilities are added to the plane. He estimates developmental flight testing will need to continue at full capacity for at least another year to “complete the planned testing of the new capabilities and attempted fixes for the hundreds of remaining deficiencies.” It will simply be impossible to complete operational testing by the 2018 deadline.

There is still a long way to go to complete the development phase of the JSF program, but rather than budgeting to resource that adequately, program officials seem to be focused more on expanding future procurement budgets.

To complicate matters even further, the program is losing testing personnel right at this critical juncture. The test centers have a turnover rate of approximately 20 percent on a normal basis. DOT&E reported that the recent departures are not being replaced. Dr. Gilmore also reports the program has started laying off people including maintenance staff, engineers, and analysts. The layoffs have started a cascading effect where many of those left are now looking for other jobs before they can be laid off.

Dr. Gilmore pointed out that how “the program will be able to complete the volume of work remaining at the integrated test centers while the staffing begins to ramp down is not known.”

This is all further evidence of program mismanagement. There is still a long way to go to complete the development phase of the JSF program, but rather than budgeting to resource that adequately, program officials seem to be focused more on expanding future procurement budgets. JSF Program officials both inside the government and at Lockheed Martin have repeatedly expressed their desire to ramp up from low rate initial production. They want Congress to authorize a block buy of 465 planes—with commensurate large pre-payments—for the United States and foreign military partners beginning in 2018. But not one official has expressed the need for funding the extra people and extra flight hours essential to keeping the development program from sliding further behind.

Ramping up production means we will be buying more airplanes that will require ever more fixes in order to be deployable. The GAO has already estimated it will cost $1.7 billion to upgrade planes bought early in the program just to fix the deficiencies so far identified in development testing. These fix-costs will certainly rise as the services continue buying new F-35s and as the more stressful operational testing gets started in the next few years.

There are 175 F-35s operational worldwide. In 2017 the DoD will get 80 new F-35s plus 100 more in 2018. That's 355 F-35s being delivered that can't go into combat and will have to go back to the depot for major rebuilds when developmental and operational testing has discovered and then designed all the fixes required (and then confirmation-tested those fixes to make sure they actually fix the problem). Operational testing and evaluation likely can't be completed any sooner than fall 2021, and that means those 355 F-35s will be non-combat-capable until at least 2023 and more likely 2024 or 2025. In other words, those 355 (plus lots more delivered after 2018) can't go to war for another seven to nine years.

As new problems are identified, the schedule and cost will be affected. And most certainly no funds have been programmed for fixing the far larger number of deficiencies that will be uncovered in the growing backlog of remaining developmental tests—not to mention the additional deficiencies sure to be uncovered in the subsequent operational tests. Ramping up production instead of funding adequate development and testing may stick the services and the taxpayers with hundreds of unusable F-35s because the DoD budget can’t afford the fixes necessary to make them combat capable. These planes would then become little more than very expensive sources of spare parts on the flight line.

Future Testing on Shaky Ground

The most worrisome news in this report is that officials in the Air Force and the Joint Program Office seem to be ramping up production and simultaneously slow-rolling future testing of the F-35. Dr. Gilmore reports that “plans and support for preparing for adequate IOT&E have stagnated.”

Not only has the Joint Program Office failed to create an adequate operational testing plan, it has failed to fund and test the equipment essential to conduct the tests.
DOT&E Table Page 7
The Air Force identified 7 "Must Fix" deficiencies during Block 2B testing for the current version to meet IOC standards. Only 4 of 7 were corrected before the announcement. (Source: DOT&E)

As evidence, he reports that the Joint Program Office has not created a realistic plan to provide production representative aircraft for combat testing. Dr. Gilmore says the program will not be able to produce enough F-35s in the necessary final configuration to proceed with operational testing. “Due to the lengthy program delays and discoveries during developmental testing, extensive modifications are required to bring the OT aircraft, which were wired during assembly to accommodate flight test instrumentation,…into the production representative configuration required,” the report states. It goes on to say that more than 155 modifications have to made to the 23 planes needed for the upcoming combat (“operational”) testing and that some of these have not even been contracted yet, meaning that the start of IOT&E will be further delayed.

Not only has the Joint Program Office failed to create an adequate operational testing plan, it has failed to fund and test the equipment essential to conduct the tests. This includes no funding for flight-testing the Data Acquisition Recording and Telemetry pod, an instrument mounted to the F-35 that is used to simulate the aircraft’s weapons. This is essential for reporting and analyzing the results of each simulated weapons firing. There can be no such tests until the pod is cleared for function and safety in conditions that the plane will fly during the engagement and weapons testing.

The report also states that the simulation facility needed for the most complex and combat-realistic of the operational test scenarios is still not on track to be delivered on time, despite 15 years of Joint Program Office promises that it would be. This is the Verification Simulator, which is supposed to provide multiple ultra-realistic, thoroughly test-validated pilot cockpit simulators operating together to enable operational testing of multi-ship tactical scenarios with large numbers of advanced threats. It’s the only way to test many of the F-35’s capabilities because the test ranges cannot realistically replicate the full spectrum and quantity of targets and threats the F-35 combat formations would confront. Beginning in 2001 Lockheed Martin engineers were under contract to create this complex simulator facility, but the project had fallen so far behind that DOT&E questioned whether it would be ready in time for operational testing. Rather than reinvigorating that project, the JPO moved the entire simulator development to a Navy lab. That lab is now in the throes of trying to take over this monumental design, fabrication, and verification testing task. According to the DOT&E memorandum, the Verification Simulator will not be ready for the currently planned IOT&E start date in 2018—and perhaps not until two or more years later.

The Last Honest Assessment of the F-35 Program?

This DOT&E memo clearly exposes the Air Force’s F-35 IOC announcement as nothing more than a publicity stunt.

Unfortunately, Dr. Gilmore’s memo may prove to be one of the last honest assessments of the F-35 program the Congress, White House, DoD, or American people receive. Dr. Gilmore’s position as Director, Operational Test & Evaluation is an appointed one, made by the President. He has proven himself to be an independent, principled actor. He has resisted the temptation that several, though certainly not all, of his predecessors failed to resist: to act on behalf of their future employers in the defense industry by signing off on ineffective operational test plans or watering down reports of operational test failures to make it appear as though all is well for continued program funding.

And so it may be again in a few months. With a new Administration, there may well be a new head of operational testing. Unless a competent and courageous operational tester, one not beholden to industry, occupies that office, the men and women who have to take these weapons into combat will be in danger of receiving flawed tools that could cost them victory and their lives. With all the evident foot-dragging that has taken place so far, a skeptical observer could be forgiven for believing that those in charge of the F-35 program may be attempting to run out the clock on Dr. Gilmore’s tenure.