The U.S. Air Force has significantly increased its investment in cutting-edge jet engine technology by expanding contracts with General Electric (GE) and Pratt & Whitney, a Raytheon subsidiary. This expanded funding is aimed at propelling forward the development of advanced engines under the Next Generation Adaptive Propulsion (NGAP) program, a key initiative designed to power the future of military aviation.
The announcement, detailed in a Pentagon contracting notice on January 27, underscores the military’s push to advance engine technology despite uncertainty surrounding the broader Next Generation Air Dominance (NGAD) initiative.
The NGAP program initially focused on developing advanced engines for a next-generation stealth fighter jet, envisioned as the centerpiece of the NGAD initiative. However, the strategic trajectory of the NGAD program remains unclear following a comprehensive review in 2024 and shifts in defense priorities under the Trump administration.
The Air Force appears intent on keeping propulsion technology development on track, regardless of the uncertainty surrounding the NGAD jet itself. The new contracts will bolster efforts to mature engine technology and reduce development risks.
According to the Pentagon’s statement, the contracts aim to enhance “technology maturation and risk reduction” for prototype engines. This work includes critical design, analysis, testing, and integration with potential future weapon systems.
The ultimate goal of the NGAP program is to develop a propulsion system featuring a flexible architecture adaptable to a wide range of future aircraft designs and mission types.
Such adaptability is seen as essential for future air combat scenarios, where multi-role capabilities and dynamic mission requirements are expected to be the norm. The Pentagon is also prioritizing a digital transformation in the propulsion industry, further highlighting the importance of these contracts.
Importantly, no immediate funds were disbursed to either company at the time of the award, reflecting the long-term nature of the program’s development goals.
The initial NGAP contracts awarded in August 2022 included funding for multiple aerospace giants — GE Aerospace, Raytheon’s Pratt & Whitney, Boeing, Lockheed Martin, and Northrop Grumman. Each was allocated $975 million to launch technology-maturation and risk-reduction initiatives.
With the latest January 27 announcement, the total contract value for each of the remaining companies, GE and Pratt & Whitney, has risen to $3.5 billion. The list of vendors has now been streamlined to just these two engine developers, marking a more focused approach to achieving NGAP’s ambitious goals.
Initially, the NGAP engines were intended to power a next-generation fighter jet that would succeed the F-22 Raptor. However, evolving defense strategies have led to the exploration of alternative concepts.
These include lower-cost designs and configurations aimed at increasing the capabilities of existing platforms like the F-35 Joint Strike Fighter. Additionally, NGAP engines may be leveraged for uncrewed systems, potentially enabling aerial drone controllers or other innovative roles.
The NGAP program builds upon lessons learned from the Adaptive Engine Transition Program (AETP), a previous joint initiative with Pratt & Whitney and GE Aviation.
The defining feature of NGAP engines, including the General Electric XA102 and Pratt & Whitney XA103, is their adaptive cycle technology. This allows the engines to dynamically adjust their bypass ratios in flight, optimizing for either fuel efficiency or additional thrust depending on mission requirements.
Such technology provides significant operational flexibility. For instance, a tactical aircraft could conserve fuel during long-range transit and then switch to high-thrust mode upon reaching a combat zone.
These advancements are seen as particularly critical for future conflicts in regions like the Pacific, where aerial refueling assets may be vulnerable and forward-operating bases scarce.
GE has previously claimed that its XA100 engine, a predecessor to the XA102, is 25% more fuel-efficient than the current Pratt & Whitney F135 engine used in the F-35 fleet. Additionally, the XA100 reportedly provides 10-20% more thrust in certain flight profiles.
Pratt & Whitney’s President of Military Engines, Jill Albertelli, has highlighted the strategic importance of these technological advancements. “This technology is critical to maintaining air superiority, which is why Pratt & Whitney has made significant investments in research and development and advanced manufacturing,” Albertelli said in an earlier statement.
Challenges and Congressional Support
Despite the promise of adaptive cycle engines, the path forward has not been without hurdles. In 2023, the Air Force shifted its focus away from the AETP, opting instead to upgrade the existing Pratt & Whitney F135 engine for the F-35 fleet.
This decision was met with mixed reactions. While it was seen as a pragmatic move to maintain operational readiness, it raised questions about the future of adaptive engine technology.
Congress, however, intervened by approving additional funding to ensure that AETP development continued, laying the groundwork for the current NGAP initiatives.
Even as the future of the NGAD combat jet remains uncertain, the Air Force’s investment in NGAP suggests a broader strategic hedge. The development of advanced propulsion systems could benefit not only future crewed fighter jets but also uncrewed systems and other military aircraft.
By maintaining momentum in engine development, the Air Force is positioning itself to adapt to shifting defense priorities and emerging technological trends.
With contracts now expanded to $3.5 billion for each company, GE and Pratt & Whitney are tasked with delivering the next leap in propulsion technology—one that could redefine the future of air combat and sustain U.S. air superiority for decades to come.
As defense strategies continue to evolve, the NGAP program stands as a testament to the Air Force’s commitment to innovation, readiness, and maintaining its edge in a rapidly changing global security environment.
