WASHINGTON — Lockheed Martin’s decision to publicly back a brand new next-generation engine for the F-35 — breaking with the Pentagon’s move to upgrade the fighter’s current Pratt & Whitney-made engines — drew a forceful rebuke from Pratt.
Greg Ulmer, executive vice chairman for aeronautics, said in a Wednesday interview with Breaking Defense on the Paris Air Show that the corporate supports the Adaptive Engine Transition Program for the F-35 fighter jet.
“I’m going to advocate, and I do advocate, for [AETP], one other engine,” Ulmer told Breaking Defense. “I feel a few of the approaches today are very short sighted and never considering a longer-term view.”
In an email to Defense News, Lockheed Martin said an AETP engine would offer greater power and cooling capabilities that may carry the F-35 beyond upcoming Block 4 upgrades. Block 4 is predicted to present the F-35 recent sensors, the power to hold more weapons and advanced electronic warfare capabilities, amongst other upgrades.
“We stand able to support and proceed to work with the U.S. government on the aptitude and performance upgrades that best support their requirements for the F-35 for a long time to come back — including an engine upgrade,” Lockheed Martin said. “AETP technologies deliver more power and greater cooling capability, which is required as we modernize the F-35 beyond Block 4.”
In an announcement to Defense News, Pratt & Whitney said Ulmer’s statement “undermines” the Pentagon’s budgetary decision to back the Engine Core Upgrade, the corporate’s name for its plan to modernize the fighter’s current F135 engines.
“AETP is a technology that can feed into [sixth-generation] fighter platforms,” Jill Albertelli, Pratt & Whitney’s president of military engines, said in an announcement. “Lockheed Martin desires to put an unproven adaptive engine on a single engine fighter jet, whatever the hefty price tag and the numerous delay in delivering critical capabilities to the warfighter at a time of urgent need.”
Albertelli noted the Pentagon has not yet defined a set of capabilities that the following set of upgrades beyond Block 4 should carry. And she or he said Pratt’s planned upgrade of the F135 engine, coupled with an updated power thermal management system, could provide enough power and cooling needs for the F-35 throughout the lifetime of this system.
The F-35 is predicted to fly until 2070, Lockheed said, which implies further upgrades are required for the a long time to come back with a purpose to stay ahead of emerging threats. An upgraded engine shall be needed to supply the aircraft with greater capabilities, readiness, range and thrust, the F-35 manufacturer added.
Lockheed also noted that each General Electric Aerospace and Pratt & Whitney are developing their very own AETP engines. GE’s adaptive engine known as the XA100 and Pratt’s is the XA101.
But while GE has consistently pushed for putting its adaptive engine within the F-35, Pratt maintains an adaptive engine is healthier suited to a sixth-generation aircraft similar to the Next Generation Air Dominance platform currently under development by the U.S. Air Force.
The Air Force was intrigued by the increased power and cooling abilities an adaptive engine would bring to its F-35As over an upgrade to the prevailing F135 engine. However the adaptive engine’s inability to slot in an F-35B variant, flown by the Marine Corps, and questions over how suitable it will be for the Navy’s F-35C version meant the Air Force was the one service seriously all in favour of an adaptive engine.
The Pentagon decided the price of funding each engine options can be too great and announced a choice to go together with the Engine Core Upgrade within the fiscal 2024 budget proposal. The department didn’t request funding for AETP.
However the House Armed Services Committee this month proposed a version of the FY24 National Defense Authorization Act that may add greater than $588 million for AETP, alongside funding the Engine Core Upgrade.
Ulmer’s comments in Paris were a departure from his previous approach to the F-35′s future propulsion system, when he opted not to select a side.
In an interview with Defense News in September 2022, Ulmer said he was “agnostic” over whether an adaptive engine or an upgrade to the F135 was the higher solution to go. Ulmer said on the time that Lockheed’s role is to supply the Pentagon with information on what the F-35′s power and cooling needs shall be, and that the department would ultimately make the choice.
“It’s not mine to come to a decision, it’s the shopper’s,” Ulmer had said.
Stephen Losey is the air warfare reporter for Defense News. He previously covered leadership and personnel issues at Air Force Times, and the Pentagon, special operations and air warfare at Military.com. He has traveled to the Middle East to cover U.S. Air Force operations.