Jet engine manufacturer Pratt & Whitney (P&W) still plans to deliver a major upgrade to the Lockheed Martin F-35 fighter by 2029.
The RTX subsidiary is under contract with the Pentagon to design and produce a new core for the F135 engine that powers the F-35.
That initiative, known as the Engine Core Upgrade (ECU), aims to deliver a substantial improvement to onboard electrical power generation from the existing F135 system, which is currently being operated outside design specifications.
“We’re in a really good place,” says Jennifer Latka, the outgoing vice-president for F135 engines at P&W. She spoke with reporters ahead of the Air & Spaces Forces Association Warfare Symposium, which begins on 13 February in Denver, Colorado.
In addition to the recent delivery of the 1,200th F-35 powerplant, Latka says engineering and manufacturing design work on the ECU is progressing.
P&W has more than 500 employees assigned to the programme, which is scheduled to produce an initial design by mid-2025 and begin engine testing in 2026.
The company is targeting 2029 to field a finished product to F-35 operators, who will install the ECU module as part of normal maintenance operations.
“We are on track to hit all of those milestones,” Latka says. “Design is going very well on ECU.”
The goal of the ECU programme is to address a projected deficit of electrical power on the F-35. Improvements to onboard sensors and avionics since the jet’s initial design have forced operators to run power generation and cooling systems outside design tolerances.
While P&W has repeatedly said the current engine can supply the necessary power, it does necessitate more frequent engine overhauls and higher sustainment costs.
A November contract announcement from the Pentagon says P&W’s final ECU design must provide at least double the current system demand for air cooling.
The engine maker says its focused on meeting technical requirements while keeping the programme on budget.
“We’re being very disciplined on cost,” Latka notes. “We’re being very disciplined on manufacturability [and] producibility, so that when we do cut into production, we can do so without any hiccups.”
P&W won the ECU contract in large part by making the case that a core upgrade to the existing F135 propulsion system would be cheaper, faster and simpler than developing an entirely new engine.
The ECU modernisation package from P&W beat a competing proposal from GE Aerospace, which had offered an entirely new engine for the F-35.
However, political uncertainty in Washington could still disrupt P&W’s plans for a smooth ECU rollout.
While the programme was funded in the 2024 defence budget, Congress has yet to actually pass a necessary law to enact the spending plan. The entire government, including the Department of Defense, is currently operating with a temporary spending measure known as a continuing resolution (CR).
Latka notes that while passing the full-year budget is “imperative” for all defence programmes, P&W is not currently experiencing disruptions.
“I think for ECU we absolutely need the fiscal year 2024 budget approved, [but] I don’t see it as pushing out our in-service date of 2029,” she says.
That could change if lawmakers fail to pass the budget altogether and opt to use more long-term CRs to fund the military.
Senior leaders at the Pentagon have said the disruptions to procurement programmes will build the longer CR funding is used.
“We usually don’t plan any new contract awards toward the first quarter of the fiscal year because we are usually under a CR,” assistant army secretary Doug Bush said in October at the Association of the US Army conference.
The Pentagon is now deep into the second quarter of its 2024 fiscal year, which began on 1 October 2023.
“A CR that runs past the first quarter is a dramatically different situation,” noted Bush, who is the army’s top procurement official.
Despite the uncertainty, Latka remains confident in P&W’s ability to maintain development work on ECU.
“We have identified funding to continue,” she notes.
At the close of her tenure at the helm of P&W’s F135 business, Latka is highlighting the company’s accomplishments in sustainment and mission readiness of the engine system, which she says is exceeding programme targets.
“The programme target is 6% non-mission capable,” Latka says. “For well over a year, we’ve been sitting at around 3.5% non-mission capable.”
The non-mission capable figure refers to the percentage of all in-service F135 engines not ready for operational use at a given time.
