Next-Gen US Fighter Jet Engine Program Postponed to 2030 Due to Supply Chain Troubles
The U.S. Air Force’s highly anticipated sixth-generation jet engine, developed under the Next Generation Adaptive Propulsion (NGAP) program, has hit a significant roadblock. Originally planned to complete by late FY 2027, the engine prototype will now not be ready before mid-FY 2030, as per the latest FY26 budget documents. The two-and-a-half-year delay is reportedly caused by supply chain challenges, according to the Air Force and confirmed in a detailed Breaking Defense report.
What is the NGAP Program?
The NGAP (Next Generation Adaptive Propulsion) program is one of the Pentagon’s most advanced defense efforts aimed at powering the future of American air superiority. It’s designed for the U.S. Air Force’s Next Generation Air Dominance (NGAD) fighter jet, now known as the F-47, a future replacement for the F-22 Raptor. NGAP engines are meant to be adaptive, variable-cycle propulsion systems, enabling real-time adjustments between fuel efficiency and thrust depending on flight demands.
This adaptive capability could give U.S. fighters an unmatched edge in both long-range missions and high-intensity dogfights, something not possible with today’s engines. These technologies are considered 6th-generation propulsion breakthroughs and were earlier explored under the Adaptive Engine Transition Program (AETP).
Who's Building the Engines?
Two top American defense giants are competing head-to-head in NGAP development:
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GE Aerospace
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Pratt & Whitney (a Raytheon Technologies subsidiary, now RTX)
Both firms received contracts in 2022, originally capped at $975 million each, which were expanded to $3.5 billion per company in 2025—a strong signal of the Pentagon’s faith in the program. By February 2025, both firms had completed detailed design reviews, a major milestone allowing them to begin fabricating prototypes.
Despite the delay, both GE and Pratt & Whitney say they are meeting their internal timelines and remain committed. “We are executing the NGAP contract schedule as proposed,” said GE Aerospace. Pratt echoed the sentiment, adding that it is working closely with suppliers using advanced digital design models to improve manufacturing efficiency.
Adaptive Engine Technology & NGAP Timeline (U.S. Air Force)
| Year | Milestone |
|---|---|
| 2007 | ADVENT (Adaptive Versatile Engine Technology) launched by DARPA and the U.S. Air Force to explore variable-cycle engines capable of switching between high thrust and fuel efficiency. |
| 2012 | ADVENT evolves into AETD (Adaptive Engine Technology Demonstrator). Development of GE’s XA100 and Pratt & Whitney’s XA101 begins to demonstrate core adaptive engine capabilities. |
| 2016 | AETD transitions into AETP (Adaptive Engine Transition Program) to mature adaptive engine tech for F-35 and NGAD. Focus shifts to developing full-scale prototypes. |
| 2022 | GE successfully completes first full engine test of the XA100; Pratt & Whitney continues XA101 development. Both engines demonstrate adaptive 3-stream tech. |
| 2023 | Advanced studies begin on XA102 and follow-on engines under early NGAP (Next-Generation Adaptive Propulsion) initiatives. GE and Pratt complete Critical Design Reviews (CDR) for conceptual 6th-gen propulsion. |
| 2025 (Planned) | Prototype fabrication begins under NGAP by GE Aerospace and Pratt & Whitney. Engines expected to be tailored specifically for NGAD aircraft and optionally manned platforms. |
| 2027 (Original Target) | Prototype engine tests and downselect decision expected. However, timelines begin shifting due to budget constraints and industrial base delays. |
| 2030 (Updated Target) | New target for prototype readiness and flight demonstration of NGAP engines due to supply chain challenges and the need for advanced materials and integration tests. |
What Makes NGAP Special?
The adaptive engine technology behind NGAP allows engines to switch between three airflow modes, offering both increased fuel efficiency and maximum thrust depending on mission requirements — a massive leap beyond traditional fixed-cycle engines. It also offers thermal management, vital for future fighters with advanced sensors and directed-energy systems.
Though initially envisioned to power the F-47 fighter during President Trump’s current term, this delay means early variants of that aircraft may fly with interim engines until NGAP reaches maturity.
Why the Delay?
The Air Force attributes the slip to global supply chain disruptions, likely tied to lingering effects of COVID-19, inflation, materials shortages, and industrial base bottlenecks. These issues have affected advanced manufacturing timelines across the entire defense sector.
Moreover, FY26 budget documents show a drop in funding from $439.9 million in FY25 to $330.3 million in FY26, indicating a shift in program phase and tighter resource alignment. The Air Force clarified that the reduction reflects a transition from design to fabrication, not a loss of interest or urgency.
What’s at Stake?
With the Trump administration pushing hard to fly the F-47 before the end of President Trump’s second term, this delay makes it unlikely that the aircraft will debut with a fully mature sixth-gen engine. Instead, the early versions of the F-47 may have to rely on interim propulsion solutions, possibly upgraded legacy engines.
However, once complete, NGAP engines could power not just the F-47 but a range of future combat aircraft, drones, and even re-engined legacy fighters—thanks to its platform-agnostic architecture.
The NGAP delay is a reality check on the complexities of cutting-edge defense programs. While disruptions in the global supply chain are to blame, the strong commitment from the Pentagon and contractors shows the strategic importance of this next-gen propulsion system. Once complete, NGAP promises to revolutionize fighter jet performance, ensuring the U.S. maintains air dominance well into the 21st century.
Until then, the wait continues—but the ambition remains sky-high.
✍️ This article is written by the team of The Defense News.
