F135 Depot Network Maturing, Engine Availability Improved by 60%

P&W concurs with and has acted on GAO’s engine sustainment recommendations, with substantial progress achieved over the past year

East Hartford, Conn. July 19, 2022

Pratt & Whitney (P&W) continues to work closely with stakeholders across the F-35 enterprise in support of an effective and efficient F135 sustainment program that delivers the highest levels of propulsion readiness for our warfighters at an affordable cost to taxpayers. The sustainment challenges noted in the Government Accountability Office’s report are well understood, with comprehensive action plans in place that are yielding positive results.

“As we reflect upon the past two years, it is clear that F135 sustainment has turned the corner,” said Jen Latka, Vice President, F135 Program at P&W. “The timeline for recovery has been pulled to the left by years and engine availability has improved significantly. While there is still more work to do, we have seen tremendous progress across the enterprise – a testament to the hard work and dedication of the joint government-industry team.”

Depot Progress

The F135 sustainment network more than doubled the number of power modules it produced in 2021 over 2020 and is on track to grow 60% in 2022 through the increased capacity provided by international and contractor logistics site depots. Regional F135 depots in the Netherlands, Norway and Australia recently achieved Initial Depot Capability and are now supporting the global fleet. The F135 Heavy Maintenance Center (HMC) at Tinker Air Force Base, the heart of the network, produced 3.5X more power modules in 2021 than it did in 2020 and is on track to once again exceed its annual target.

As a result of this progress, overall engine availability -- measured as Mission Impaired Capability Awaiting Parts (MICAPs), also known as Aircraft on Ground (AOGs) -- has improved by approximately 60% at the end of Q2 2022 over the end of 2021.

Engine Reliability

With more than 500,000 flight hours logged, the F135 has been proven in the field as the safest, most reliable fighter engine P&W has ever built in its 97-year history. Reliability is measured by the amount of time the engine stays on-wing, or Mean Flight Hours Between Engine Removals (MFHBR). The current production configuration of the F135 is achieving double the specification for MFHBR.

As with any engine program, reliability is a continuous effort. Through the Component Improvement Program, P&W is focused on leveraging operational data and its engineering expertise to make improvements. It’s important to underscore the primary driver of the power module shortage was insufficient depot capacity, which led to a backup of depot work – not the reliability of the F135.

Commitment to Affordability

P&W is committed to maintenance cost reduction. As part of the normal propulsion lifecycle, sustainment costs will rise and fall driven by scheduled maintenance cycles. Propulsion sustainment cost is primarily driven by scheduled maintenance over the life of the program. P&W has identified opportunities to reduce the cost of the first scheduled maintenance visit by approximately 40%, which is project to save more than $14 billion over the life of the program.

GAO’s Recommendations

P&W concurs with both recommendations made in the GAO’s report on F135 engine sustainment:

  • Engine Availability Strategy: The F135 sustainment strategy – which is designed, funded, and contracted for a 6% Non-Mission Capable (NMC) rate – is currently not aligned with warfighter readiness expectations. P&W has experience successfully executing many different readiness constructs across its product portfolio and is poised to adapt based on user needs. Altering the current construct requires alignment across the enterprise.
  • Forecasting Spare Parts Needs: Pratt & Whitney has proven forecasting and modeling tools to support fleet planning. Over the past 12 months, P&W has worked with the Joint Program Office to align the ground rules and assumptions of these forecasts. Changes in funding availability for timely procurement of spare parts remains a challenge. P&W continues to focus on identifying spare parts requirements that meet engine availability and readiness levels.