The vast majority of Defense Department aircraft, including all of the military’s most advanced fleets, fell short of their mission readiness goals over the past decade, according to a recent Government Accountability Office report.
Only three of 46 different types of aircraft that the GAO studied hit their mission-capable rate goals during most of the period studied, from fiscal 2011 to 2019. Those platforms include aerial tanker, anti-submarine, bomber, cargo, command-and-control, and fighter planes, as well as rotary-wing aircraft. GAO did not provide exact fleet capability figures, citing operational security concerns.
The Air Force’s nearly 50-year-old UH-1N Hueys, which have on average flown nearly 15,000 hours over the course of their lifetimes, exceeded their MC goal all nine years, according to the report. The Air Force also had more Hueys available than expected in three of those years.
The other two aircraft that usually achieved more than their annual MC goals were the Navy’s EP-3E Aries II anti-submarine aircraft (seven of nine years), and the Navy’s E-6B Mercury airborne nuclear command post (five of the nine years).
About half of the aircraft did not meet their MC goals at any point in the nine-year period, including the Air Force’s F-22 Raptor, F-15C/D Eagle, F-16 Fighting Falcon, B-1B Lancer, C-17 Globemaster III, and the C-130J Super Hercules.
Former Defense Secretary James N. Mattis in 2018 directed the Air Force and Navy to boost F-16, F/A-18, F-22, and F-35 fleet readiness to 80 percent by October 2019. No Air Force planes hit the mark, though the F-16 and F-35 came close. The USAF inventory reached an average MC rate of about 70 percent in fiscal 2019.
“None of these aircraft had achieved the 80 percent mission-capable goal, when mission-capable rate data are averaged for each day in fiscal year 2019,” the report noted.
Air Force Chief of Staff Gen. Charles Q. Brown told senators ahead of his confirmation hearing that the service was moving away from MC rates in favor of a more holistic view of readiness.
“The Air Force has made improvements in the readiness of its units. However, the continued high demand for Air Force capabilities continues to impact recovery,” Brown wrote. “If confirmed, I will continue the effort [former Chief of Staff Gen. David L. Goldfein] has put on readiness recovery with a focus on recruiting, training, and retaining high-quality Airmen, driving down the average age of our aircraft fleets through modernization, and working with our combatant commanders on balancing current operations tempo with time for our Airmen to train for full-spectrum combat operations.”
F-35 Joint Strike Fighter
The Air Force’s F-35A and the Marine Corps’ F-35B did not reach annual aircraft availability goals from fiscal 2013 to 2019, while the Navy’s F-35C carrier variant hit that threshold in two of those years. For MC rates, the F-35A and F-35C reached their targets in two fiscal years, while the F-35B met its target once.
Last year, GAO said 52 percent of the F-35 fleet was ready to take on a combat mission, largely due to a lack of available spare parts. In 2018, the Defense Department had a backlog of 4,300 F-35 parts, though the Pentagon and Lockheed Martin are working to improve that pipeline.
DOD has also purchased F-35 parts in advance, an approach that hasn’t always worked out in its favor as the aircraft is updated over time.
“For example, 44 percent of purchased parts were incompatible with aircraft the Marine Corps took on a recent deployment,” according to the GAO. In addition, “DOD’s networks for moving F-35 parts around the world are immature, and F-35 customers overseas have experienced long wait times for parts needed to repair aircraft.”
F-35 sustainment costs are estimated at more than $1 trillion over the 60-year life of the program, making it DOD’s most expensive weapon system by far. Total operations and sustainment costs have ballooned from $55.6 million in fiscal 2011 to $2.2 billion in fiscal 2018, while maintenance costs have increased from $15.8 million to $758.4 million in the same time, according to the report. The F-35A accounted for the majority of those costs.
“The Air Force and Marine Corps recently identified the need to reduce their sustainment costs per aircraft per year by 43 [percent] and 24 percent, respectively,” GAO said.
When it comes to maintenance, GAO argues the Defense Department has a “limited capability to repair parts when they break.” The watchdog noted that, as of April 2019, the F-35 program “was failing to meet four of its eight reliability and maintainability targets, which determine the likelihood that the aircraft will be in maintenance rather than available for operations, including metrics related to part removals and part failures.”
In fact, the GAO claims DOD’s ability to repair parts is eight years behind schedule.
“DOD originally planned to have repair capabilities at the depots ready by 2016, but the depots will not have the capability to repair all parts at expected demand rates until 2024,” the report said. “As a result, the average time taken to repair an F-35 part was more than six months, or about 188 days, for repairs completed between September and November 2018—more than twice as long as planned.”
The Joint Program Office has taken several steps to address this issue, including taking less time to activate a depot, making sure parts are available earlier, and initiating performance-based logistics contracts to incentivize performance and cost improvements.
Air Force Magazine previously reported the F-35A had an MC rate of 61.6 percent in fiscal 2019.
Lockheed’s F-22 Raptor is one of the Air Force’s newest aircraft, averaging 12 years old and nearly 1,900 flying hours per jet. But the fighter fleet “faces challenges with its low-observable system and spare parts,” which were “exacerbated by the extreme damage at Tyndall Air Force Base, [Fla.], from the effects of Hurricane Michael” in 2018, GAO said.
F-22 aircraft availability and MC rates fell over the nine-year stretch. According to program officials, those low numbers were tied to degraded stealth coating, supply shortages, and more frequent use than anticipated.
“After 2017, the Air Force devoted additional funding for the F-22 to help procure time-sensitive spares, repairs, and consumable parts,” GAO said.
Total operations and sustainment costs for the F-22 increased from $2.3 billion in fiscal 2011 to $2.4 billion in fiscal 2018, due mainly to an increase in flying hours and scheduled engine depot inductions, according to the report.
Air Force Magazine previously reported the F-22 had a 50.6 percent MC rate in fiscal 2019.
F-16 Fighting Falcon
F-16 fighter jets exceeded their annual aircraft availability goals in nearly half of the nine years studied, narrowly missing the mark in four other years. However, the fleet failed to meet any of its MC goals during the same time period.
“The F-16’s inability to meet its mission-capable goals is due in part to the age of the fleet and related supply and maintenance challenges. The F-16’s aircraft availability rate and mission-capable rate decreased slightly during the time period,” the report said.
The service plans to start replacing the F-16 with the F-35 around 2040. Fighting Falcons, with an average age of 29 across the fleet, have flown for an average of 7,100 hours per C-model and 6,300 hours per D-model, according to the report.
“Some F-16 aircraft are operating beyond their expected service life with maintenance and supply challenges. Planned actions to mitigate these challenges include extending the service life of the aircraft, identifying all parts that need to be replaced during the inspection phase of maintenance, and identifying alternate vendors for parts,” GAO added.
Operating and sustaining the F-16 cost about $5.2 billion in fiscal 2011, which fell to $4.1 billion in fiscal 2018 as the fleet shrank. Maintenance itself increased in fiscal 2014, 2015, and 2017 because of unscheduled repairs and replacement of structural components and radar-absorbing material, according to GAO.
Air Force Magazine previously reported the F-16C saw a 73 percent MC rate in fiscal 2019, while the F-16D came in at 70.4 percent.
The roughly 35-year-old F-15 is averaging around 8,500 flight hours per aircraft, and is expected to remain in service through 2045. The fleet exceeded its aircraft availability goals in one-third of the years studied, but never met its MC goals, according to the report.
“The F-15C/D’s aircraft availability rate and mission-capable rate both increased during the time period,” GAO said. “According to program officials, the aircraft availability and mission-capable rates were at their lowest in fiscal year 2011 due to F-15C/D manning challenges as avionics trained technicians shifted to maintaining the F-22 fleet, reductions in the F-15C/D combat air force fleet—including transfers to the Air National Guard—and radar upgrades that increased unscheduled maintenance downtime.”
Total O&S costs decreased from about $1.9 billion in fiscal 2011 to about $1.4 billion in fiscal 2018, due in part to “significant decreases in unit operations.”
Air Force Magazine previously reported the F-15C’s MC rate was 70 percent in fiscal 2019, outpaced by the F-15D at 72.5 percent and F-15E at 71.3 percent.
Air Force leaders have long lamented the B-1’s abysmal MC rates, which at one time dipped into the single digits as years of overuse in the Middle East nearly broke the fleet. The Lancer did not meet any of its annual aircraft availability or MC goals from 2011 to 2019, but USAF officials are optimistic about the future.
Air Force Global Strike Command boss Gen. Timothy M. Ray told Air Force Magazine in December 2019 that the fleet’s readiness had improved thanks to a focus on fleet management, additional maintenance help from Boeing, success in working through technical orders, and by addressing problems with the aircraft’s egress systems. That work brought the B-1 back into the deployment rotation.
In September, the fleet completed the eight-year, $1.3 billion Integrated Battle Station upgrade to modernize the jet’s datalinks, cockpit displays, and test system.
A structural fatigue test on the B-1, underway since 2012, is now expected to wrap up next year. An Air Force Materiel Command spokesman said the findings of the test are “driving a fleet safety analysis, which includes analyzing data and conducting research. Results are then applied to the fleet to determine which aircraft are at risk and when inspection and repairs should begin.”
Air Force Magazine previously reported the B-1 saw a 46.4 percent MC rate in fiscal 2019.
C-17 Globemaster III
The roughly 16-year-old C-17 fleet averages around 15,300 flight hours per aircraft and is facing challenges associated with age and maintenance, according to the GAO. The Globemaster III failed to meet MC or aircraft availability rates from 2011 to 2019, as both figures slightly fell during this period. However, the fleet came within 1 percentage point of the goal in two of the years studied.
The number of aircraft undergoing thorough maintenance, scheduled or not, was largely to blame.
“Officials said that the C-17’s aircraft availability and mission-capable rates were lower in fiscal year 2019 than in fiscal year 2011 due to an increase in the amount of time needed to complete a scheduled, field-level maintenance inspection; a depot-level upgrade to the latest airplane tracking system used by the Federal Aviation Administration’s air traffic control; and supply challenges,” GAO said.
C-17s logged an MC rate of 82.2 percent in 2019, Air Force Magazine previously reported.
C-130J Super Hercules
Though the average age of the fleet is less than a decade old, the C-130J already “faces increasing maintenance requirements and parts obsolescence,” according to the GAO. The fleet met its aircraft availability rates in roughly half of the years studied but never hit its MC goals.
“According to Air Force officials, the aircraft availability rate decline was largely due to an increase in the amount of time the aircraft spent in depot maintenance,” GAO wrote.
“Depot inductions increased 400 percent overall and the associated downtime increased by 436 percent mostly due to the aircraft’s procurement history and programmed depot maintenance schedule. Older aircraft began to require recurring maintenance as newer aircraft continued to receive the initial maintenance,” according to the report.
The C-130J fleet recorded an MC rate of 77 percent in 2019, Air Force Magazine previously reported.