PUBLISHED on August 7, 2025, 04:08 PM EDT – Key Points and Summary – In a tale of two different design philosophies, this article compares the modernized 4.5-generation F-15EX Eagle II with China’s 5th-generation J-20 stealth fighter.
-The J-20 is a purpose-built stealth interceptor designed to strike first from beyond visual range. The F-15EX is a non-stealthy “missile truck” that compensates with overwhelming firepower, superior maneuverability, and advanced electronic warfare.
An F-15EX Eagle II from the Defense Contracting Management Agency Boeing St. Louis, sits on the flight line at Selfridge Air National Guard Base, Michigan, June 11, 2025. The aircraft visited the base as part of a site activation task force, an initial step to prepare the 127th Wing with the right infrastructure, personnel, and support the incoming F-15EX and KC-46 Pegasus missions . (U.S. Air National Guard photo by 1st Lt. Elise Wahlstrom)
-While the J-20’s stealth gives it the advantage at a distance, the author concludes the F-15EX’s superior agility and internal 20mm cannon would likely make it the winner in a close-range dogfight.
F-15EX Eagle II vs. J-20 Fighter: A Showdown That Could Happen…
The Chengdu J-20 “Mighty Dragon” is China’s first and foremost stealth fighter. Despite entering service less than a decade ago, the J-20n quickly became the new cornerstone of the PLAAF, with over 200 units believed to be in service in China currently.
The F-15EX Eagle II, on the other hand, represents a deep modernization of the venerable F-15 Eagle, designed to keep it relevant in modern warfare. Both fighters possess state-of-the-art equipment.
The Eagle II vs The Mighty Dragon
The F-15EX and the J-20 were built with very different philosophies in mind. The F-15EX is an upgrade of the legacy F-15. It is built for multirole dominance, capable of both air superiority and strike missions. It leverages the robust airframe of the original F-15 but integrates modern systems to remain relevant in a fifth-generation battlefield.
The F-15EX upgrade introduced several improvements that significantly altered the interior of the frame. From its electronic warfare capabilities to improved avionics, the F-5EX is well-equipped to handle today’s challenges.
The J-20, on the other hand, is China’s first stealth fighter.
It is purpose-built for stealth and long-range interception, designed to counter high-value targets such as AWACS and tankers while avoiding direct dogfights.
When designing the fighter, China sought an aircraft capable of matching American fifth-generation aircraft, such as the F-22 or F-35. With this in mind, the Chinese built the J-20 for standoff engagements rather than close-up dogfights.
This is evident in its design, which prioritizes stealth and speed over maneuverability.
Stealth: The J-20’s Biggest Advantage
Stealth is one of the most significant differentiators between the two. The J-20 was designed from the ground up with stealth in mind. It features internal weapons bays, radar-absorbent materials, and a shape optimized to reduce radar cross-section.
China’s J-20 Stealth Fighter. Image Credit: Chinese Weibo/Screenshot.
These features make it difficult to detect at long range, giving it a potential first-shot advantage in beyond-visual-range (BVR) combat.
This is in stark contrast to the F-15Ex, which was built on a fourth-generation airframe. While not stealthy due to its legacy airframe and external weapons carriage, it compensates with advanced electronic warfare capabilities.
Its Eagle Passive Active Warning Survivability System (EPAWSS) allows it to jam enemy radars, deceive incoming missiles, and operate effectively in contested environments. Additionally, the F-15EX retains a 20mm M61 Vulcan cannon, giving it a distinct edge in close-range dogfights, whereas the J-20 lacks an internal gun, suggesting a doctrinal preference for BVR engagements.
Avionics and Electronics
In terms of avionics and sensors, the F-15EX is equipped with the AN/APG-82(V)1 AESA radar, one of the most powerful radars in service. It also features a modern cockpit with large-area displays and an open mission systems architecture that allows for rapid upgrades.
The aircraft is fully integrated into the U.S. military’s network-centric warfare ecosystem, including Link-16 and other datalinks, which enable real-time information sharing with other platforms, such as the F-35, AWACS, and ground stations.
The J-20 is believed to use the Type 1475 AESA radar and advanced electro-optical targeting systems. The radar has undergone several improvements since the J-20’s initial debut. Its range has reportedly been upgraded to around 3x of the original model, which has made it significantly more threatening.
While its sensor fusion capabilities are improving, they remain less transparent and likely less interoperable than those of Western systems. This gives the F-15EX a significant advantage in networked combat scenarios.
Engine Performance and Armament
When comparing speed, range, and maneuverability, the F-15EX stands out with its twin F110 engines that provide superior thrust and agility. It can reach speeds of Mach 2.5 and has a service ceiling of 65,000 feet. Its thrust-to-weight ratio and aerodynamic design make it highly maneuverable, especially in close combat.
The J-20 is also no pushover when it comes to engine performance. It is powered by two WS-10C engines (with future upgrades to WS-15), is optimized for long-range missions and stealthy penetration rather than close-range dogfighting. It has a slightly higher service ceiling at 66,000 feet but lower top speed and maneuverability. The lack of thrust vectoring further limits its agility compared to the F-15EX Eagle II.
Weapons and payload capacity further highlight the differences. The F-15EX can carry up to 22 air-to-air missiles, including the AIM-120D AMRAAM and AIM-9X Sidewinder. It is also compatible with hypersonic weapons and long-range strike munitions, such as the AGM-158 JASSM.
This makes it one of the most heavily armed fighters in the world. The J-20, constrained by its stealth design, carries fewer missiles in its internal bays, typically the PL-15 for BVR and PL-10 for short-range engagements.
It does, however, have four external hardpoints, which brings its total carrying capacity up to 24,000 lbs. The absence of a gun limits its versatility in close combat. Overall, the F-15EX offers superior firepower and flexibility.
Who Wins in the End?
So, which aircraft would win in a fight? The F-15EX Eagle II is an exceptional aircraft; unfortunately, the J-20 was explicitly built for air superiority. With its superior stealth capabilities, advanced avionics, and arsenal, the J-20 wins in a head-to-head battle. It could strike first and disengage before the F-15EX can respond. That being said, there are scenarios in which the F-15EX could outperform the J-20 in a battle.
In close-range engagements, the F-15EX wins out with its superior mobility and more versatile armament. Its avionics and sensor-fusion technology also give the F-15EX a technological edge to help compensate for the lack of stealth technology.
About the Author: Isaac Seitz
Isaac Seitz, a Defense Columnist, graduated from Patrick Henry College’s Strategic Intelligence and National Security program. He has also studied Russian at Middlebury Language Schools and has worked as an intelligence Analyst in the private sector.
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Gary
August 8, 2025 at 1:28 pm
How come every fly by night so called “expert” gives an opinion about non combat rested airframes (J 20) etc against an airframe with over 100 kills (F 15)? blah blah blah
Adrian
August 8, 2025 at 2:28 pm
When you compare the kill counts, top on the list is BF109. It must be the mightiest jet human being ever made.
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