GAO Reports Highlight New F-35 Deficiencies
(Source:; posted April 26, 2018)

By Giovanni de Briganti
PARIS --- A new fault discovered in the F-35 engine’s main fuel throttle valve can cause the aircraft to move suddenly and without stopping until the engine is shut down,” the Government Accountability Office revealed in a report published April 25.

This is only one of the latest deficiencies that continue to be discovered in the F-35, even as the program faces continuing challenges to fix deficiencies that have already been identified, while the first F-35 operational deployment to Japan has revealed shortcomings and deficiencies in its supply chain and its Autonomic Logistic Information System, according to a second, separate report also published April 25 by the GAO.

This and other findings reported by the GAO contradict recurring statements by prime contractor Lockheed Martin and the F-35 Joint Program Office that the program is improving and that it has fixed most of the faults and deficiencies that have been identified.

The GAO also warns that “The program faces the risk of additional design changes to address these issues, until developmental testing is completed, and others that could be discovered in operational testing through 2019.”

The first report is GAO’s “Weapon Systems Annual Assessment,” while the second, “Warfighter Support: DOD Needs to Share F-35 Operational Lessons Across the Military Services,” is the unclassified version of a report published in March 2018. (Links at foot of page)

Technology Maturity and Design Stability

The first report, “Weapon Systems Annual Assessment,” offers a usefully condensed update of the program’s technical and financial status. It notably says that, as of January 2018, F-35 development has already cost $64.745 billion (in FY 2018 dollars), with another $714 million to remaining until the end of development.

Procurement is expected to cost the US government $216.5 billion for 2,097 aircraft, as 359 have already been contracted for at a cost of $68.9 billion.

GAO also notes that at December 2016, the unit cost of the F-35 is $143.84 million (in FY18 dollars), or 74% more that the initial, October 2001 estimate.

The report makes the following points regarding the program:

-- “The program office is still facing challenges in delivering ALIS capabilities, for all the variants.”

-- “The program also continues to address deficiencies with other, non-critical technologies, such as the next-generation helmet, which can produce a “glow” effect on the visor making night landings on a carrier difficult.” (Given that the F-35 is not equipped with a head-up display, and that its helmet is the pilot’s principal source of flight and mission data, we dispute the GAO’s assessment of the helmet technologies as “non-critical.”)

-- The program “continues to analyze potential solutions to the excessive vibrations that F-35C pilots currently experience during catapult launch from aircraft carriers.”

-- “More recently, the program discovered that the F-35 engine’s main fuel throttle valve can cause excessive thrust, causing the aircraft to move suddenly and without stopping until the engine was shut down. According to the program office, they are in the process of implementing hardware and software changes to resolve the problem.”

-- “The contractor reported they are implementing design changes to address deficiencies with the tires of the F-35B, the Marine Corps’ aircraft.”

-- “Pilots have reported experiencing symptoms of oxygen deprivation during flights of the F-35A. As a result, test officials grounded the aircraft at one Air Force base in June 2017. Despite the program’s review of these cases, it has not been able to identify the root cause of this issue.

-- “The program faces the risk of additional design changes to address these issues until developmental testing is completed, and others that could be discovered in operational testing through 2019.”

Production Readiness

-- “Aircraft deliveries are increasing slowly and totaled 266 production aircraft as of January 2018. “

-- “The government temporarily halted deliveries (although not production) for 1 month after identifying corrosion between the aircraft’s surface panels and the airframe because the contractor did not apply primer when the panels were attached. A DOD official anticipates that a significant amount of rework will be required on aircraft delivered without the primer; however, the scope of work and the severity of the issue has yet to be fully assessed.”

-- “Part shortages and quality control are the top production risks for the prime contractor and its suppliers. For example, part shortages with the radar and canopy are two challenges the program office faces. The contractor is working with suppliers to improve the production process to address these issues as production increases and the need to sustain a growing operational fleet continues.”

Other Program Issues

“The Air Force and Marine Corps have declared initial operational capability (IOC) for the F-35A and F-35B, respectively. The Navy has scheduled F-35C IOC for August 2018. However, the Navy’s criteria to declare IOC includes the completion of operational testing, which is scheduled to end in September 2019. At this time, the Navy has not delayed IOC despite the program’s delays to operational testing.”

-- “Despite numerous delays, partially attributable to software instability, the program plans to complete developmental testing in March 2018. The program has completed flight and mission systems testing partially by combining or removing a significant number of test objectives.”

-- “The program office is also preparing to start operational testing for the F-35; however, the aircraft that will be used are currently early production models that require upgrades and retrofits before they can be used.”

-- “According to the program office, some deficiencies identified during developmental testing will not be fully resolved until the program’s planned follow-on modernization period. However, the technical scope and schedule of this modernization period have yet to be finalized.”

-- “In January 2018, the program office provided Congress with its plans for the transition between the development program and modernization; however, the plans are under review and have yet to be approved.”

Marine Corps Lessons Learned report

The second GAO report released on April 25 is titled “Warfighter Support: DOD Needs to Share F-35 Operational Lessons Across the Military Services,” and reveals that the GAO in March published a report on F-35 lessons learned that was classified at the Pentagon’s request.

“In March 2018, we issued a classified report that addressed these provisions. In that report, we (1) described the warfighting capabilities the F-35 brings to the Pacific and assessed any operational challenges the Marine Corps faces; (2) assessed the extent to which the Marine Corps is prepared to support distributed operations with the F-35 in the Pacific; and (3) determined the extent to which the Marine Corps records and DOD shares F-35 operational lessons learned across the Marine Corps, the Air Force, and the Navy. DOD deemed some of the information related to the first two objectives to be classified, which must be protected from loss, compromise, or inadvertent disclosure.”

Although less detailed than the previous report, this one also contains some surprising revelations. One, for example, is that the GAO considers that the “F-35’s advanced stealth allows pilots to escape detection by enemy…infrared sensors,” which is a physical impossibility given the size of the F-35’s exhaust plume and its temperature, reported to be over 1,000-degree Celsius.

Other points of interest include:

-- The Marine Corps “is facing challenges operating in the [Pacific] area. In particular, it is uncertain how long the F-35 can effectively operate if ALIS becomes disconnected from the aircraft.”

-- “The Marine Corps has also encountered several challenges with the F-35’s supply chain since beginning flight operations in January 2017. Further details are provided in our classified report,” to which we do not have access.

-- Lessons learned during Steel Knight exercise “included the need for maintaining network connectivity, and the limited reach-back support for ALIS.”

-- Lessons learned from Red Flag 2016 “included the need for ensuring that classified facilities meet basic cooling and power requirements for housing the ALIS servers.”

-- During the transfer of VMFA-121 squadron to Iwakuni, Japan, while its “aircraft were transferred to Japan through Alaska, ALIS was moved through Hawaii because of concerns about how the freezing temperature would affect the logistics system.”

One conclusion from the above is that the Marine Corps’ idea of deploying the F-35B to austere, advanced bases to provide close air support for assault Marines are wholly impracticable.

The vacuity of the concept was already shown by an insurgent attack against Camp Bastion, in Afghanistan, when a dozen Taliban broke into the base and destroyed six US Marine Corps AV-8B Harriers and seriously damaged two more.

But it is now also becoming clear that the F-35 needs network connectivity for ALIS to function; that ALIS servers need “basic cooling and power requirements” to function, and preferably inside “tents with strict environmental requirements.”

All of this points to infrastructure of such size and complexity that makes forward deployment in a combat zone – and especially in a beach-head – impossible under combat conditions.

Click here for the Warfighter Support: DOD Needs to Share F-35 Operational Lessons Across the Military Services report (15 PDF pages), and

Click here for the Weapon Systems Annual Assessment report (206 PDF pages), both on the GAO website.


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