US Air Force's first F-47 fighter will take off in 2028 years before its next-gen engine is ready.

On July 27, 2026, General Dale R. White, U.S. Air Force Director of Critical Major Weapon Systems Programs, confirmed at the Life Cycle Industry Days in Dayton, Ohio, that the Boeing F-47 sixth-generation fighter remains on track for its 2028 maiden flight, two years before its designated Next-Generation Adaptive Propulsion (NGAP) engine will be ready for integration. This schedule mismatch requires initial test flights to rely on an interim propulsion arrangement to validate airframe flight controls, software, and structural mechanics within a tight 36-month Engineering and Manufacturing Development timeline. The strategy prioritizes early air vehicle flight qualification while General Electric and Pratt & Whitney complete adaptive-cycle engine testing ahead of targeted 2030 aircraft integration.

The U.S. Air Force will fly the first Boeing F-47 in 2028 using temporary legacy or early non-production engines, as the 35,000-to-40,000 lbf NGAP adaptive engines will not reach integration readiness until 2030. This two-phase testing approach allows Boeing to evaluate core airframe performance across the 1,000-nautical-mile combat radius envelope while propulsion manufacturers conclude ground trials for the primary 185-aircraft procurement fleet.

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Unless the NGAP propulsion schedule changes, the first F-47 may need to fly with an interim engine or a non-production version that allows aerodynamic and systems testing to begin before the final propulsion configuration is ready. (Picture source: Pratt & Whitney)

On July 27, 2026, General Dale R. White, the U.S. Air Force's Director of Critical Major Weapon Systems Programs, confirmed that the first F-47 fighter remains scheduled to fly in 2028 and that the aircraft has entered Engineering and Manufacturing Development (EMD), a phase that produces flight test aircraft and establishes the configuration for initial production. The immediate program objective is now measurable: Boeing must take the F-47 from its March 21, 2025, development contract to first flight in roughly three years, manufacture a small but undisclosed number of test aircraft and prepare priced options for Low-Rate Initial Production. The U.S. Air Force plans to acquire at least 185 operational F-47s, close to the 187 F-22s procured after the original 750-aircraft Raptor plan was terminated.

The principal schedule problem is propulsion, because the F-47 is expected to fly in 2028 while its adaptive-cycle engines are not expected to be ready for aircraft integration before 2030. Unless engine development moves forward by two years, the aircraft that conducts the first flight will probably use an interim engine, an early non-production NGAP configuration, or another propulsion arrangement that does not yet provide the capabilities planned for the operational fighter. Boeing received the F-47 EMD contract on March 21, 2025, after the U.S. Air Force paused the NGAD award in May 2024 and reassessed the aircraft’s cost, mission and force design assumptions. The contract moved the F-47 from experimental work into airframe maturation, subsystem integration, software integration, ground qualification, developmental flight testing and production of the aircraft required for evaluation.

An EMD must also establish manufacturing processes, tooling, quality controls, supply chain capacity and a production-representative configuration before the U.S. Air Force can exercise its Low-Rate Initial Production (LRIP) options. The first-flight objective of 2028 gives Boeing about 36 months from award to flight, compared with the five years between Lockheed Martin’s selection in 2001 and the first F-35 flight in 2006. The comparison does not mean that the F-47 is progressing from a clean-sheet design, as the Air Force and DARPA had already flown classified X-planes for hundreds of hours during the five years preceding the contract. This prior work reduces uncertainty at contract award, but the 2028 milestone still requires Boeing to complete several key steps.

These include the F-47's detailed design, fabricating the first airframe, installing flight controls and mission equipment, conducting structural and ground-vibration tests, completing power-on and engine-run sequences, performing low- and high-speed taxi trials, and obtaining flight clearance before the end of Donald Trump's second presidential term. The F-47 is being developed as a penetrating air superiority fighter, like the F-22 Raptor, rather than as a direct multirole equivalent of the F-35A. Its planned combat radius exceeds 1,000 nautical miles, compared with 590 nautical miles for the F-22 and 670 nautical miles for the F-35A. The published threshold therefore represents an increase of more than 410 nautical miles over the F-22, equal to at least 69%, and 330 nautical miles over the F-35A, equal to at least 49%.

The increase is intended to reduce dependence on more vulnerable KC-135 and KC-46A tankers during operations across the western Pacific, where air bases, tanker tracks and operating areas can be separated by hundreds of nautical miles. A 1,000-nautical-mile radius would allow the F-47 to launch from bases farther from Chinese missile coverage, use less predictable ingress routes and retain more fuel for combat or diversion to another airfield. The U.S. Air Force also requires a maximum speed above Mach 2, preserving the F-22’s high-speed interception and ability to quickly repositioning while extending the distance over which the aircraft can conduct that mission. Range and speed requirements together increase internal fuel demand, inlet and engine performance requirements, aerodynamic heating and thermal management loads, meaning that the F-47 must achieve them while retaining a sufficiently low radar signature for operations against long-range surface-to-air missiles, airborne early warning aircraft and advanced fighters such as the Su-57, Su-75, J-20 and J-50.

The planned force of 185 F-47s represents only one component of the much larger Next Generation Air Dominance (NGAD) combat architecture, as the crewed fighter is intended to operate with more than 1,000 unmanned Collaborative Combat Aircraft (CCAs). That quantity would equal at least 5.4 CCA drones for every crewed aircraft, although CCAs will also operate with F-35As and possibly other aircraft. Earlier Air Force planning used a broader force-design assumption of two CCAs for each of 200 NGAD fighters and 300 F-35As, which also produces a requirement of 1,000 uncrewed aircraft. The distinction matters because it confirms that the Air Force is not planning to attach a fixed group of five loyal wingmen permanently to each F-47.

Instead, commanders could assemble formations according to mission requirements, assigning some CCAs as forward sensors, some as electronic warfare aircraft, some as decoys and others as missile carriers, allowing the F-47 to limit its own signature. A CCA carrying an active radar, jammer or communications relay can reveal its position while the F-47 remains passive, while a weapon-carrying drone can increase the formation’s missile load without increasing the F-47’s size or reducing its internal fuel. The cost relationship remains central because 1,000 CCAs will not create affordable mass if their unit price approaches that of conventional fighters after sensors, weapons, autonomy software, and low-observable features are added. The General Atomics YFQ-42A and Anduril YFQ-44A are the first Increment 1 CCA designs, and the Air Force has already established a combat radius objective exceeding 700 nautical miles.

That figure places the initial autonomous aircraft at least 110 nautical miles beyond the F-22’s range and within 300 nautical miles of the F-47 objective. The requirement was increased after Air Combat Command personnel concluded that earlier concepts lacked the endurance needed for Pacific missions. A shorter-range CCA might be inexpensive to procure but could not accompany an F-47 through a 1,000-nautical-mile mission unless it launched from a more exposed base, received aerial refueling, or accepted a one-way mission profile. Increasing radius forced designers to allocate more internal volume to fuel, improve propulsion efficiency and control drag, all of which can increase aircraft size and cost. White stated that the CCA program moved from first flight to a live weapons release in nine months, a pace partly possible because a drone does not require the same human-safety certification burden as a crewed fighter.

The Air Force retains control of the mission autonomy architecture, allowing General Atomics, Anduril and other suppliers to compete for later software increments rather than tying autonomy development permanently to the original airframe manufacturer. The F-47 and CCAs are also intended to use the same mission system architecture, which would permit common interfaces for targeting data, weapons assignment, sensor management and software upgrades across the formation. The two-year gap between the first F-47 flight and expected NGAP integration is the most concrete technical risk currently visible in the schedule. General Electric is developing the XA102 and Pratt & Whitney the XA103 under contracts whose ceilings were increased to $3.5 billion per company, with work extending through 2032.

Both manufacturers completed assembly-readiness reviews for their engines in May 2026, initial hardware has been procured, and prototype fabrication is moving toward ground testing. The Air Force requested $513.7 million for the Next Generation Adaptive Propulsion (NGAP) program in FY2027 and projected $905.7 million for FY2028 and $865 million for FY2029, followed by annual funding near $300 million in FY2030 and FY2031. This expenditure profile indicates that engine fabrication and testing will be intensifying during the same period in which the first F-47 is expected to fly. The XA102 and XA103 are three-stream adaptive-cycle engines that can redirect airflow among the core, conventional bypass stream, and a third stream.

During cruise, the third stream can increase effective bypass ratio, lower fuel consumption and provide additional cooling, while combat operation can redirect airflow to increase thrust. The engine, with afterburning thrust, is expected to produce 35,000 to 40,000 lbf, while earlier adaptive-engine work targeted fuel-efficiency gains of up to 25% and thrust increases of up to 20% over fixed-cycle engines. Additional cooling capacity is as important as thrust because the F-47's future radars, electronic warfare transmitters, processors and secure communications equipment generate heat that must be removed without enlarging external apertures or compromising stealth. An interim propulsion arrangement would therefore allow the U.S. Air Force to begin the F-47 flight testing in 2028, but it would divide the test campaign into at least two technically distinct configurations.

An early engine could support validation of takeoff and landing behavior, flight control laws, basic handling qualities, structural loads, cockpit functions and selected avionics, while the later adaptive engine would require renewed testing of acceleration, range, climb, thermal loads, electrical generation and high-altitude performance. The integration problem is not limited to fitting a different engine inside the same compartment. The final engine determines inlet airflow demand, inlet geometry, compressor-face distortion limits, fuel flow, engine-mount loads, center of gravity, exhaust temperature, nozzle dimensions, cooling requirements and the aircraft’s rear-aspect radar and infrared signatures. A change in mass or airflow can require revisions to flight control software, inlet control, fuel management and structural reinforcement.

A larger engine or different nozzle can also alter the external mold line, which would affect radar signature testing and invalidate part of the low-observable qualification completed with the earlier configuration. Historical fighter programs have flown prototypes with non-production engines, but the consequences depend on how closely the interim and final propulsion systems match in size, weight, airflow, and output. The first F-47 flight in 2028 should therefore be treated as the beginning of developmental testing, not evidence that the operational configuration is complete. The more consequential milestone will be the first flight with the selected production-representative NGAP engine and a mission system load capable of supporting representative combat testing, in order to avoid a prolonged interval between first flight and operational fielding in the mid-2030s.

Written by Jérôme Brahy

Jérôme Brahy is a defense analyst and documentalist at Army Recognition. He specializes in naval modernization, aviation, drones, armored vehicles, and artillery, with a focus on strategic developments in the United States, China, Ukraine, Russia, Türkiye, and Belgium. His analyses go beyond the facts, providing context, identifying key actors, and explaining why defense news matters on a global scale.

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