U.S. Air Force Expands F-15EX Eagle II Fleet to 149 Fighter Jets With Production Through 2031.

The U.S. Air Force is moving to expand its F-15EX Eagle II fleet well beyond earlier plans, with the 2026 defense budget outlining 149 aircraft through 2031 and keeping production active into FY2031. The larger buy would give the service more long-range firepower and weapons capacity while preserving stealth aircraft for missions where survivability is critical.

The F-15EX combines heavy payload, extended range, modern sensors, and advanced electronic warfare systems to support air defense, long-range strike, and high-volume missile employment. Its expanding role highlights a broader push to build combat mass alongside F-35A and future F-47 fleets without relying on the most advanced aircraft for every mission.

Related Topic: U.S. F-15EX and MQ-28 Ghost Bat Teaming Marks New Era in Indo-Pacific Manned-Unmanned Air Combat

U.S. Air Force F-15EX Eagle II fighter: the service now plans to procure 149 aircraft through 2031, expanding the non-stealth fighter’s role as a high-payload, long-range missile carrier alongside the F-35 and future F-47. (Picture source: U.S. Department of War/Defense)

According to the International Fighter Aircraft Global Market Report 2026-2031 published by Defence iQ, the FY2027 U.S. Air Force budget request includes 24 F-15EX aircraft valued at $2.66 billion, while procurement is now programmed through FY2031 and the 2026 defense budget points to 149 aircraft between 2026 and 2031. The scale suggests that the Eagle II is moving from a relatively limited F-15C/D replacement effort toward a more substantial element of the future U.S. tactical aviation force.

The F-15EX acquisition originated as a rapid solution to the structural aging and declining readiness of the F-15C/D fleet. In July 2020, the U.S. Department of Defense awarded Boeing a $22.89 billion indefinite-delivery/indefinite-quantity contract covering F-15EX design, integration, manufacturing, testing, aircraft delivery, sustainment, modifications, spares, training and technical support, with an initial delivery order capped at approximately $1.19 billion.

That contract gave Boeing’s St. Louis fighter production operation a long-term framework under which successive F-15EX lots could be ordered rather than requiring a completely new contracting structure for each batch. The original Air Force plan centered on replacing F-15C/D fighters, but the program has repeatedly changed in size as Washington reassessed fighter capacity, F-35 delivery schedules and the number of combat aircraft required for future high-intensity operations.

The F-15EX program began in 2019, when the U..S. Air Force approved a rapid-fielding requirement to address the deteriorating F-15C/D fleet. The first aircraft was accepted in March 2021, demonstrating one of the programme’s principal industrial advantages: because the Eagle II builds on an already mature F-15 production and support base, the Air Force could introduce a new fighter substantially faster than would be possible with an entirely new aircraft design.

The latest budget profile shows that the acquisition is no longer being treated as a short bridge program. Procurement is now scheduled through FY2031, while the FY2027 request for 24 aircraft represents one of the programme’s most substantial annual buys, and the report also identifies $16.9 million for post-production support as the operational fleet and its sustainment requirements expand.

The F-15EX Eagle II is the newest U.S. version of Boeing’s long-running F-15 fighter family, but it is substantially modernized compared with the F-15C/D aircraft it is intended to replace. It is a two-seat, twin-engine 4.5-generation fighter built around high payload, long range and rapid fielding, retaining the Eagle’s aerodynamic performance while incorporating digital flight controls, modern avionics, electronic warfare equipment and an open mission-systems architecture.

Two General Electric F110-GE-129 turbofan engines power the aircraft, and it integrates the Eagle Passive Active Warning and Survivability System, or EPAWSS, along with updated F-15 Operational Flight Program software. These improvements are designed to keep the fighter relevant in a battlespace dominated by increasingly capable radars, electronic attack, long-range missiles and rapidly changing software-defined threats.

Its most important distinction from the F-35 is weapons capacity. Boeing states that the F-15EX has a maximum payload capacity of about 29,500 pounds, or 13,300 kilograms, and can carry up to 12 AIM-120 AMRAAM air-to-air missiles, giving a single Eagle II a considerably deeper missile magazine than a stealth fighter operating with weapons confined to internal bays.

That figure helps explain why the Air Force can rationally buy more non-stealth F-15EX fighters while simultaneously investing heavily in the F-35 and F-47. The three aircraft solve different parts of the same combat problem: the F-35 prioritizes low observability, sensor fusion and penetration; the F-47 is being developed for future air dominance with even greater survivability, reach and crewed-uncrewed integration; the F-15EX prioritizes missile volume, external payload, speed, range and rapid generation of combat sorties.

In practical terms, an F-35 penetrating closer to hostile air defenses can use its sensors and low observability to develop targeting-quality information while an F-15EX operating farther from the highest-threat area provides additional weapons. That creates a division of labor in which one fighter maximizes survivability and sensing while the other supplies the magazine depth needed to turn targeting information into more engagements.

The F-47 will push this logic further rather than make the F-15EX automatically irrelevant. Boeing received the F-47 engineering and manufacturing development contract in March 2025, and the report identifies approximately $3.5 billion for the program in FY2026, with research and development funding expected to exceed $5 billion in FY2027. The sixth-generation fighter centers on survivability, range, sensing, networking, and crewed-uncrewed teaming, positioning it for the most demanding air-dominance missions.

The Eagle II therefore occupies a different place in the force structure. It does not need to penetrate every advanced Chinese or Russian surface-to-air missile engagement zone to be useful; it can contribute from outside those zones by carrying large numbers of air-to-air weapons, long-range strike weapons or future oversized munitions that are difficult to accommodate internally on smaller stealth fighters.

This distinction matters because stealth is operationally decisive in the most heavily defended parts of a battlespace, but it is not required for every sortie. F-35s and, eventually, F-47s can focus on missions where penetration, advanced sensing, and survivability against modern integrated air defenses are essential, while F-15EX aircraft can carry larger external weapon loads from less exposed positions or operate where the threat environment does not justify committing scarce stealth aircraft.

The Indo-Pacific gives that force structure particular relevance. Former U.S. Air Force Chief of Staff Gen. David Goldfein has previously pointed to the Pacific’s long distances and the combination of F-15 range and payload as reasons the Eagle II became more attractive when the service examined different fighter mixes for a major regional conflict.

China presents exactly the type of operational problem that makes missile capacity and range increasingly important. U.S. combat aircraft could have to operate across enormous distances while confronting Chinese fighters, long-range air-to-air missiles, integrated air defenses and attacks against forward air bases, creating pressure to maximize the number of weapons carried by every fighter reaching the combat area.

A U.S. Air Force F-15EX Eagle II assigned to the 85th Test and Evaluation Squadron taxis at Kadena Air Base, Japan, on July 8, 2026. The deployment highlights the fighter’s growing Indo-Pacific role as the U.S. Air Force expands the F-15EX fleet, combining long range, advanced electronic warfare systems and increased missile capacity to complement F-35 and future F-47 operations. (Picture source: U.S. Department of War/Defense)

The F-15EX is already being connected directly to that Indo-Pacific posture. In June 2026, F-15EX aircraft deployed again to Kadena Air Base in Japan for testing and familiarisation, with the U.S. Air Force saying the work would support the Eagle II’s eventual integration into Kadena’s long-term mission and strengthen combat readiness across the Indo-Pacific.

That makes the fighter’s large missile magazine strategically relevant, not just a specification-sheet advantage. In a Pacific air battle, F-35s could operate forward as survivable sensors and shooters, while F-15EX fighters farther back contribute additional AMRAAMs or long-range effects, increasing the number of engagements a formation can sustain before aircraft must return to base to rearm.

This creates the basis for a weapons-carrier role in which a stealth fighter detects, identifies, or helps generate targeting data while an F-15EX contributes additional missiles or stand-off weapons from farther outside the highest-risk area. Boeing is also positioning the aircraft for long-range kill chains and networked operations with other crewed and uncrewed aircraft, reinforcing the Eagle II’s potential value as both a shooter and a communications node.

The same logic applies to homeland air defense, one of the missions explicitly identified for the Eagle II. Replacing aging F-15C/D fighters with F-15EX aircraft gives the U.S. Air Force a modern fighter that can maintain alert missions, intercept aircraft, and defend U.S. airspace without consuming flight hours from F-35 units whose low-observable characteristics are more valuable in contested expeditionary operations.

Operationally, this division of labor reduces the need to treat every fighter sortie as a stealth mission. Routine air defense, homeland alert, permissive-environment strike, cruise-missile defense and other missions can be assigned to an aircraft with high speed and a deep weapons magazine, reserving finite F-35 availability for missions where penetrating survivability provides a decisive advantage.

This division of labor could become increasingly important as the U.S. Air Force introduces Collaborative Combat Aircraft. The report says CCA procurement enters a dedicated aircraft acquisition line in FY2027, with $996.5 million requested for procurement, $150.5 million in advance procurement and another $1.37 billion in research and development. More than 150 uncrewed combat aircraft could be acquired before FY2031, creating a force in which F-35s, F-47s, F-15EX fighters and autonomous aircraft contribute different combinations of survivability, sensor reach, weapons capacity and acceptable operational risk.

The report describes this as part of a broader North American market shift in which fifth-generation recapitalization, sixth-generation development, uncrewed combat aircraft and renewed investment in selected fourth- and 4.5-generation fighters are proceeding simultaneously. The F-35 remains the largest acquisition effort, but the F-15EX has expanded beyond earlier planning and is now funded through FY2031 as the F-47 and CCA programs also accelerate.

That mix suggests the U.S. Air Force is increasingly building around complementary mission roles rather than expecting one fighter type to do everything. An F-35 brings penetration and advanced sensing, an F-47 is intended to deliver next-generation air dominance, CCA aircraft add lower-cost uncrewed combat mass, and the F-15EX adds a large weapons magazine and mature fighter capacity that can be fielded without waiting for a new generation of technology.

For the F-15EX, its central advantage is therefore capacity. The aircraft retains the F-15 family’s emphasis on high payload and long range while adding modern mission systems, EPAWSS, and updated operational software, creating a fighter that can carry substantial external weapon loads while operating as part of a wider networked force.

This also explains why a simple F-15EX-versus-F-35 comparison can be misleading. The F-35 is substantially better suited to penetrating dense integrated air defenses because of its low-observable design and sensor fusion, while the F-15EX offers greater external weapons capacity and can carry munitions too large for an F-35 internal weapons bay. The Air Force can gain more combat effect by combining those strengths than by forcing either fighter to replace the other.

The comparison with the F-47 is even more asymmetric. The F-47 is intended to survive and dominate inside future high-threat environments while controlling or cooperating with uncrewed combat aircraft; the F-15EX offers a mature, high-capacity fighter available years earlier and without requiring the U.S. Air Force to use an extremely advanced sixth-generation aircraft for every air-defense patrol or missile-carriage mission.

That helps explain why the F-15EX expansion does not represent a retreat from stealth or sixth-generation technology. Instead, it reflects a force-design problem: highly sophisticated aircraft are expensive, complex and potentially too scarce to provide all the combat mass required during a prolonged high-intensity campaign. A larger Eagle II fleet gives commanders another way to distribute missions according to threat level while preserving more specialised aircraft for operations where their unique characteristics are indispensable.

F-35 delays have also strengthened the argument for additional F-15EX capacity. Air & Space Forces Magazine reported in May 2026 that delays to critical F-35 upgrades contributed to the Air Force reassessing the balance between Eagle II and F-35A procurement, with service officials emphasizing the need for a fighter portfolio offering different weapons capacities and capabilities for a Pacific conflict.

The approach also responds to the industrial and readiness pressures highlighted throughout the Defence iQ report. Recent conflicts have demonstrated the importance of sustaining operations, replacing losses, maintaining munitions inventories and generating combat power over extended periods. A mixed fleet gives the U.S. Air Force more flexibility than a force dependent exclusively on a limited number of highly complex stealth aircraft.

The procurement profile is equally significant for Boeing and the U.S. combat-air industrial base. The original $22.89 billion F-15EX contract framework provides substantial production and sustainment opportunities for Boeing’s St. Louis operation, while the company is simultaneously responsible for developing the F-47, linking current-generation fighter production with the Air Force’s next major air-dominance program.

That industrial continuity has its own strategic value. Keeping F-15 manufacturing, engineering, suppliers and skilled labor active gives the United States additional fighter-production capacity at a time when Washington is increasingly concerned about its ability to replace combat losses and sustain aircraft output during a prolonged conflict.

The wider spending picture reinforces the point. The report forecasts approximately $19.4 billion in North American fourth- and 4.5-generation fighter spending between 2026 and 2031, even as fifth-generation expenditure reaches about $77.3 billion, sixth-generation programs approach $27.9 billion and loyal-wingman procurement totals roughly $15.7 billion. The categories are growing alongside one another rather than following a simple generational replacement cycle.

For the U.S. Air Force, the emerging structure is increasingly clear: stealth aircraft provide penetration and advanced sensing, CCAs add affordable combat mass and risk-tolerant capacity, and the F-15EX supplies payload, range and sortie-generating potential for missions that do not demand the same degree of low observability.

If the report’s projection of 149 F-15EX aircraft procured between 2026 and 2031 is sustained, the Eagle II will no longer look like a small bridging purchase intended only to replace worn-out F-15Cs. It will instead become a substantial part of a deliberately tiered U.S. combat-air force, giving commanders a fighter capable of carrying as many as 12 AMRAAMs while F-35s penetrate, CCAs add mass and the future F-47 tackles the most demanding air-dominance missions.

That combination could prove particularly valuable against China, where distance, missile expenditure, dispersed basing and the need to preserve scarce stealth aircraft could make magazine depth almost as important as individual aircraft sophistication. The surprise expansion of the F-15EX therefore says less about the U.S. Air Force turning back toward an older generation of fighter technology than about how it expects to fight: with stealth, autonomous aircraft and sixth-generation systems opening the battlespace, and heavily armed Eagle IIs adding the volume of fire needed to exploit it.

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Written by Alain Servaes – Chief Editor, Army Recognition Group
Alain Servaes is a former infantry non-commissioned officer and the founder of Army Recognition. With over 20 years in defense journalism, he provides expert analysis on military equipment, NATO operations, and the global defense industry.