Why the F-5 Tiger II is used as an enemy in naval training, its role in Top Gun, and the modernization of ex-Swiss F-5Ns for “red air.”
In summary
The F-5E Tiger II did not remain famous because it dominated modern combat. It became indispensable because it is useful. For decades, the US Navy and Marine Corps had a constant need: to provide their pilots with a credible adversary, flown by experts, capable of replicating the tactics and profiles of enemy aircraft. The F-5 emerged as a pragmatic solution, similar in size, maneuverability, and visual signature to certain Soviet fighters. This logic was amplified by the growing demand for realistic training in the face of so-called “near-peer” threats. Hence the strong comeback of second-hand aircraft and their modernization: a new wave of ex-Swiss F-5s has been transferred to the United States, and avionics upgrades are set to extend the fleet’s life. Popular culture then did the rest: Top Gun turned a tactical training aircraft into a myth, with the fake MiG-28.
Choosing the F-5 to play the enemy: a cold and effective calculation
The public loves stories of aerial duels. The air force loves results. Adversary Squadrons exist for one simple reason: to advance the “Blue Force” by putting it in an uncomfortable position. Not against a complacent opponent, but against pilots who know the typical mistakes, exploit blind spots, and apply tactics inspired by foreign doctrines. In this area, the F-5 had a decisive advantage: it is powerful enough to “challenge” a pilot in advanced training, without being expensive or too complex to maintain.
Technically speaking, the F-5E is not a fifth-generation fighter. It has no native sensor fusion, no standard stealth capabilities, and no modern platform-level electronic warfare. But it has the qualities that matter in close combat training: a light airframe, two simple engines, good acceleration at certain speeds, and maneuverability that remains challenging for those who face it. The numbers speak for themselves. An F-5E can reach approximately 1,700 km/h (1,060 mph) and climb to approximately 15,800 m (51,800 ft). Its “useful” range varies depending on the profile, but its carrying capacity can exceed 3,700 km (2,010 nmi) with external tanks. In terms of a “red air” mission, this makes it possible to increase the number of sorties, deploy on an ad hoc basis, and maintain a dense training schedule without tying up front-line fighters.
The key point lies elsewhere: what matters is tactical realism. In training combat, a small, agile aircraft can recreate some of the problems posed by aircraft of comparable size, such as the MiG-21, especially in scenarios where the aim is to work on energy management, positioning, visuals, and offensive/defensive transitions. The Marines and the US Navy have used this logic for decades, because it is less glamorous than flying a state-of-the-art fighter as the “bad guy,” but much more financially sustainable over time.
The job of “Aggressor”: a school of cunning rather than power
We often imagine the ‘aggressor’ as an extra. It’s the opposite. An opposing squadron pilot is paid to lose… but above all to make you lose first. His mission is not to “look good.” He must provoke errors, create confusion, and push the Blue Force to apply procedures under stress. This requires repetition, standardization of profiles, and an obsession with details.
At the heart of these systems is DACT (Dissimilar Air Combat Training). The principle is brutal: if you have only trained between identical platforms, you learn your own habits, not those of the enemy. Opposing squadrons inject diversity. They vary entry speeds, altitudes, threat axes, and “rules” of engagement. They change formation, use the terrain, and force unfavorable merges. The goal is to give pilots in training or in the process of ramping up their skills “mental libraries”: recognizing a maneuver, anticipating an exit, understanding when to break off combat or, on the contrary, force it.
This realism is not limited to piloting. It relies on instrumentation and measurement capabilities. The exercises are filmed and replayed. Trajectories are analyzed. Detection, acquisition, simulated firing, and evasion timings are dissected. This is where avionics modernization becomes a strategic issue: a useful adversary must be reliable, traceable, and compatible with modern training systems, including in complex environments.
It is also important to acknowledge a truth that is rarely admitted publicly: the armed forces have a demand for “red air” that often exceeds their organic capacity. Maintaining dedicated squadrons is expensive, but not doing so is even more costly in terms of operational effectiveness. Hence the parallel rise of private contractors and hybrid solutions. Military adversary squadrons nevertheless remain a benchmark, as they are integrated into doctrine, tactical intelligence, and state security requirements. They don’t just “fly the plane”; they play the enemy, using the enemy’s methods.
The Top Gun myth, a spotlight… and useful confusion
Pop culture has given the F-5 a second life. In Top Gun (1986), the enemy fighter is not a real MiG. It is a disguised F-5, renamed MiG-28 for the purposes of the script.
The choice was not artistic: it was logistical. They needed an aircraft that was available on American soil, could be flown by military personnel, was capable of flying close to the actors and cameras, and was visually credible as a “Soviet fighter” to a non-specialist audience. At the time, the F-5 was already part of the training and attack ecosystem. It therefore had a clear advantage.
This point deserves clarification, as it still fuels a lot of online research: “F-5 Top Gun” refers less to a specific model than to a function. The film cemented the idea that a small, agile fighter is the “typical enemy” in close combat. This has had a lasting influence on the collective imagination. In reality, there is no such thing as a “bad plane.” There are threats, distances, sensors, missiles, and tactical conditions. The aggressor is there to help you work through these variables, not to replay a scene.
This misunderstanding does have one positive effect, however: it raises awareness of a profession and training infrastructure that is often overlooked by the general public. Opposing squadrons are not a curiosity. They are a response to a structural problem: you cannot train modern crews by flying only in a “clean” environment. Credible training requires friction. The F-5, due to its size and performance, has long embodied this friction in an economical way.
There is also a perverse effect, which must be stated frankly. The Top Gun myth sometimes leads to overestimating the aircraft. The F-5 is excellent in its role as a training tool, but it is not the synthesis of current threats. Modern adversaries include dense ground-to-air networks, long-range missiles, drones, aggressive jamming, and sensor fusion. A “bare” F-5 is not enough to simulate all of this. Hence the race to upgrade and integrate more modern equipment, at least for training, safety, and compatibility.
The F-5N line and the return of the ex-Swiss, an accepted stopgap
The most concrete, and often the most sought-after, point concerns the naval versions. The F-5N is, schematically, an F-5 adapted to US Navy/USMC standards and requirements, in particular to maintain fleet life and integrate with contemporary training systems. The aim is not to transform the aircraft into a state-of-the-art fighter, but to keep it relevant for its mission: to be an available, reliable, and instrumented adversary.
The recent chain of events is illuminating. Switzerland sold a batch of aircraft that had been withdrawn from service. The transfer to the United States began with deliveries starting in March 2024, as part of a sale finalized in 2020. The package includes 22 aircraft (16 single-seat F-5Es and 6 two-seat F-5Fs), with ground equipment and associated parts, for an estimated value of approximately $32.4 million. At this price level, the logic is clear: it is less a “purchase of fighters” than a purchase of availability and airframes that are still operational. The US Navy and USMC are to share these aircraft, which illustrates the pressure on “red air” resources.
Why go for older aircraft? Because training demand cannot be controlled with slogans. Modern fleets are in high demand. Their hourly cost is high. Their airframes wear out quickly. Grounding them to play the enemy is an operational waste. Buying used airframes and modernizing them is a rational option, even if it is not flattering.
This modernization is structured around dedicated programs. The avionics modernization and standardization program, often referred to as ARTEMIS, aims to reconfigure avionics, improve flight safety (alerts, weather, fuel), and add useful capabilities for tactical training. Off-the-shelf avionics solutions are preferred in order to avoid industrial drift and keep maintenance realistic. In this context, systems such as the Garmin G3000 have been mentioned as possible building blocks for a more modern, open, and maintainable architecture.
We must be clear: this approach is a stopgap, but a smart one. It buys time. It allows the training load to be maintained while the armed forces seek more sustainable solutions, such as new dedicated adversary aircraft, more service providers, or newer platforms. As long as demand remains higher than supply, the modernized F-5 will continue to have a domestic market.
The future of adversary squadrons, between technical limitations and ongoing need
The F-5 will remain useful as long as it meets a simple ratio: tactical credibility per euro spent. But its limitations are increasing as threats evolve. Modern combat often begins beyond visual range. Superiority depends on sensors, data links, BVR weapons, jamming, and multi-platform coordination. An F-5 cannot “embody” all of this on its own.
This is where adversary squadrons play a broader role than the aircraft itself. They compensate with tactics, profiles, integration with training resources, and simulation discipline. An adversary does not need to be identical to the threat to be useful. It must force the Blue Force to apply the right processes: detect, sort, decide, communicate, engage, survive. If the F-5 can continue to create uncertainty and errors, it retains its place.
We are also seeing segmentation. Some units are switching to more modern platforms where possible, in order to offer a threat closer to that of current fighters. Others are keeping the F-5 as a “basic tool” for the fundamentals, because the fundamentals do not change. Energy management, radio discipline, situational awareness, and reading the enemy’s intentions remain human skills.
Finally, there is an industrial and political dimension that is rarely stated clearly. Western countries talk a lot about high intensity, but realistic training is expensive and faces trade-offs. If you want pilots who are ready, you pay for flight hours, training resources, maintenance, and analysis teams. The F-5 is a symbol of this tension: an old aircraft, kept in service not out of nostalgia, but because there is no simple alternative to quality training.
The link with Top Gun is, in essence, almost anecdotal. The real story is more stark, but also more interesting: Marines and airmen who agree to be “trapped” in training, over and over again, because the only lasting shame is discovering your flaws in operation.
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