Skip to main content

Acquisition of F-15EX by US Air Force: A Pragmatic Choice or an Admission of F-35’s Limitations.


In its 2025 report on the acquisition cost of weapon system programs, the Department of Defense announced the purchase of 18 new F-15EX Eagle II fighters as part of its 2025 defense budget. This decision confirms the continued use of 4.5-generation aircraft alongside stealth 5th-generation fighters like the F-35, raising questions about whether the latter can fully meet the missions originally assigned to it. Beyond a simple strategic choice, integrating the F-15EX reflects a pragmatic approach aimed at balancing operating costs, firepower, and technological complementarity.

Where the F-35 is prioritized for stealth penetration and high-tech superiority missions, while the F-15EX provides conventional strike and deterrence capabilities at a lower cost (Picture source: US DoD)


Designed to replace the aging F-15C/D, the F-15EX Eagle II represents the latest technological evolution of a proven platform. It is based on the F-15QA, a variant developed for Qatar, and incorporates significant advancements in air combat capabilities. Among its key innovations, the aircraft features a digital fly-by-wire flight control system, a glass cockpit with a touchscreen interface, and the powerful APG-82 AESA radar, which enhances target detection and engagement.

It is also equipped with the Joint Helmet Mounted Cueing System, allowing pilots to target threats simply by looking at them, and the EPAWSS electronic warfare suite, which improves survivability in contested environments. Additionally, its Open Mission System architecture enables rapid software updates to adapt to evolving threats.

With its two General Electric F100-PW-229 engines, the F-15EX offers strong performance, reaching speeds of Mach 2.5 and a range of 2,762 miles with aerial refueling. It has the highest payload capacity of any US fighter, carrying up to 29,500 pounds of ordnance, including 12 AIM-9 or AIM-120 air-to-air missiles or 24 air-to-ground munitions. The aircraft is also equipped with an M61A1 20 mm cannon. Its ability to engage targets at long range makes it well-suited for air superiority and strike missions, particularly in scenarios where stealth is not a primary requirement.

The acquisition of the F-15EX comes at a time when the F-35 program is facing significant challenges. Despite its advanced stealth features and multi-role capabilities, the F-35 remains expensive to operate, with an estimated cost per flight hour of 36,000 dollars. Ongoing maintenance issues and delays in the integration of Block IV upgrades have further complicated its large-scale deployment.

In response, the US Air Force has adopted a layered capability strategy, where the F-35 is prioritized for stealth penetration and high-tech superiority missions, while the F-15EX provides conventional strike and deterrence capabilities at a lower cost. This approach suggests that stealth, while important, is not the only factor in maintaining air dominance. Payload capacity, versatility, and operational costs are also critical considerations in modern Air Force planning.

As China and Russia rapidly modernize their air forces and develop increasingly sophisticated missile systems, the US Air Force is opting for a balanced fleet that includes both 5th-generation stealth fighters and upgraded 4.5-generation platforms.

The F-15EX addresses an immediate need by compensating for the lack of high-payload air superiority aircraft while allowing a more gradual transition toward future 6th-generation fighters, such as those under the Next Generation Air Dominance program. Its compatibility with existing F-15 infrastructure and training programs simplifies its integration, reducing overall costs compared to a full transition to stealth aircraft.

Rather than merely filling gaps in the F-35 program, the F-15EX represents a reorganization of the US Air Force’s capabilities. It demonstrates that 4.5-generation fighters remain relevant in addressing current operational and budgetary challenges. While the future of air combat is likely to be shaped by stealth and autonomous technologies, the F-15EX highlights the importance of maintaining a diverse and adaptable fleet.

The question now is whether this approach will be adopted by other major air forces as the costs of 5th-generation aircraft continue to rise and the increasing role of combat drones reshapes the dynamics of aerial warfare.


Copyright © 2019 - 2024 Army Recognition | Webdesign by Zzam