Madrid is considering acquiring the TAI KAAN fighter jet as an alternative to the F-35 Lightning II, as the European Future Combat Air System program falls behind schedule.
Summary
Spain, faced with delays in the European fighter program and rising costs associated with the F-35 Lightning II, is now considering the Turkish KAAN fighter developed by Turkish Aerospace Industries (TAI) as a replacement. This potential choice reflects a twofold concern: reducing dependence on the United States and securing advanced air capabilities in an uncertain strategic context. The KAAN, which is now beginning test flights, offers advanced features (including stealth, supercruise, and sensor networks) and is already on the export radar. For Spain, integrating this system would require a joint industrial effort, a budget adjustment, and direct involvement in European and Atlantic dynamics. The choice remains informal but marks a potential turning point in Madrid’s fighter acquisition policy.
The context of Spain’s renunciation of the F-35
Spain has long considered acquiring Lockheed Martin’s F-35 Lightning II fighter jet to modernize its air and naval forces. However, several factors have led Madrid to question this project. First, the overall cost of acquiring and maintaining the F-35 proved to be particularly high for medium-sized countries. According to specialist sources, the announced unit cost of the aircraft could exceed $100 million and, with support costs, the program for Spain could have amounted to more than €10 billion.
Second, Spanish officials have highlighted concerns about technological sovereignty: the F-35 imposes a high level of dependence on the United States, both for software updates and logistical support. Choosing the American platform risked hindering Spanish participation in future European programs. Finally, Spain is involved in the European Future Combat Air System (FCAS) program with France and Germany, whose delays and uncertainties reinforce the need for a backup plan.
Thus, Madrid’s abandonment or suspension of negotiations on the F-35 is part of a strategic move to focus its resources on European systems or those offering a better cost-benefit balance.
The KAAN program: characteristics and progress
The Turkish TAI KAAN fighter, formerly known as TF-X, is a project by Turkish manufacturer TAI to produce a new-generation combat aircraft. The prototype made its first public flight in February 2024.
From a technical standpoint, the aircraft is described as follows: length of approximately 21 m, wingspan of approximately 14 m, estimated maximum takeoff weight of 34,750 kg. It is said to be capable of reaching a speed of around Mach 1.8 and operating at a maximum altitude of close to 16,764 m.
The KAAN is designed to incorporate stealth features (reduced radar signature), internal weapon bays, active electronically scanned array (AESA) radar, and an architecture capable of handling network-centric warfare. However, it is important to note that the program is still in development and has not yet reached full operational maturity like the fighters already in service.
In terms of exports, Indonesia signed a contract for 48 units with TAI in June 2025, which is the first export order for the KAAN.
The Turkish manufacturer claims that several countries are in contact regarding acquisition or participation in the program.
The KAAN appears to be a promising fighter, but it remains a project that has not yet reached full operational capacity.
Why Spain is considering the KAAN as an alternative
There are several reasons why Spain is considering the KAAN as an alternative to the F-35. First, replacing the F-35 would allow Madrid to break away from its exclusive dependence on Washington for defense and embrace a logic of European strategic autonomy or third-party partnership. Second, with the European FCAS program delayed, Spain wants to avoid a “capability gap” between its old equipment and new-generation fighters. The KAAN could serve as a technological bridge until the FCAS is ready for service.
Third, the KAAN offers potential for industrial collaboration for Spain, through shared production, maintenance, or co-development. This could strengthen the Spanish aerospace sector and boost national industrialization within a strategic framework. Fourthly, due to the abandonment of the F-35, Spain needs to secure a credible air force for its air and naval forces, and the KAAN meets this need. Finally, the choice also reflects a budgetary trade-off: Spain can attempt to obtain more controlled acquisition and maintenance costs than those associated with the F-35, while investing in platforms more in line with its industrial and strategic priorities.
Budgetary challenges for Spain
Adopting the KAAN poses a series of budgetary challenges. The first is the purchase cost. While the F-35 had high unit costs and very heavy life-cycle costs, the KAAN could offer a less expensive model—although precise data for Spain has not yet been published. One report mentions an estimated cost of around $100 million per unit for the KAAN in certain export cases.
Next, there is the cost of commissioning, pilot training, maintenance, ammunition, logistics, and integration into the air force and navy structures. The fact that the KAAN is still in development poses a risk of cost overruns or delays. Spain must allow for budgetary margins for these uncertainties.
There is also the impact on domestic industry. Choosing an aircraft outside the American consortium or one that already exists opens up the possibility of involving Spanish companies in the supply chain. However, this requires investment in co-production, maintenance, and upgrades, which represents an initial cost but could be a gain in the medium/long term.
Finally, budgetary trade-offs with other programs must be taken into account: Spain has increased its defense budget (for example, a commitment to allocate 2% of gross domestic product) and wishes to reserve a large part of the funds for European platforms and modernization.
In short, the decision is not limited to the purchase price, but concerns the entire life cycle and interaction with industry and national strategy.
Integration into the Spanish and European forces
For Spain, the introduction of the KAAN would involve a profound transformation of the air force (Ejército del Aire y del Espacio) and the navy (Armada Española) if the naval version were chosen. In terms of equipment, it would be necessary to adapt maintenance infrastructure, train crews on the new aircraft, modify logistics chains, and ensure interoperability with NATO (NATO). The KAAN—although not American—boasts a network/NATO-compatible architecture, which is essential for a member of the Alliance.
At the European level, the stakes are high. Spain is a partner in the FCAS program, which aims to develop a generation of European fighter jets for the 2040s. Adopting the KAAN could influence industrial and strategic dynamics in Europe. It could offer an intermediate path between current aircraft (such as the Eurofighter Typhoon) and the European future, allowing Madrid to maintain credible capability without being 100% dependent on US programs. In addition, Spain could collaborate with Turkey on production, which would strengthen European industrial ties outside the traditional Franco-German circuits.
However, this integration also requires overcoming several obstacles: delivery times, engine issues (the KAAN still depends on imported engines), technology sharing arrangements, and long-term support guarantees. The KAAN’s naval option could be an added value for Spain, particularly if an aircraft carrier or CATOBAR (catapult assisted take-off but arrested recovery) system is envisaged.
In short, for integration to work, Spain will have to manage a complex industrial and operational system.
Technical and strategic obstacles to overcome
Choosing the KAAN also means facing a number of challenges. The first is technological maturity: although the KAAN has completed test flights, development is still ongoing, which poses a risk to short-term deliveries. Several analysts estimate that it will not be fully operational until the end of the decade.
Secondly, engines are a point of vulnerability: the program currently depends on imported engines (e.g., GE F110), and Turkey does not yet have a fully domestic engine in production for this platform. This could be an obstacle to exports to Spain under technology transfer conditions.
Thirdly, the strategic and diplomatic stakes are high: Spain’s purchase of the KAAN could be perceived as a departure from the American F-35/NATO chain and would have implications for the cohesion of the Alliance. Some observers refer to this as a “strategic own goal.”
Fourthly, European industrial coherence could be disrupted: Spain is a member of the FCAS program and the Eurofighter manufacturing consortium, and choosing a Turkish aircraft outside the consortium could complicate the distribution of tasks and European strategy. Finally, in terms of the budget, it will be necessary to rigorously monitor the budget, delays, and the risk of cost overruns, which will require increased rigor in planning.
Spain must therefore weigh these factors carefully before committing.
The provisional timetable and scenario for Spain
According to the information available, Spain has not yet signed a firm contract for the KAAN, but it has entered an advanced stage of consideration. A possible scenario for Madrid could be structured as follows: in the short term (2025-2030) → acquisition of transition fighters (upgrade of the Eurofighter, purchase of aircraft already in production); in the medium term (2030-2035) → order for KAAN if performance and maturity are confirmed; long term (from 2040) → integration of the European FCAS fighter.
With this in mind, Spain could order an initial batch of KAANs to fill the gap between the decommissioning of its current aircraft and the entry into service of the FCAS. This timetable is highly dependent on technical development, industrial agreements, and the funds allocated.
Another important variable is the naval version of the KAAN, which could be of interest to the Spanish Navy if it develops an aircraft carrier or a catapult-based aircraft carrier system. This could further alter requirements and investment.
Madrid will also have to manage aspects related to training, maintenance, and logistics specific to the new aircraft, which will require significant industrial and budgetary planning. The Spanish government has already allocated substantial funds in its defense plan and aims to devote a large part of it to European or cooperative systems.
The decision has not yet been finalized, but the process is underway.
Implications for Europe and NATO
Spain’s potential shift to the KAAN has repercussions beyond Madrid. At the European level, it signals a diversification of defense supplies, which could promote greater European strategic autonomy. The entry of a Turkish aircraft into European arsenals challenges the traditional channels dominated by the United States and major Franco-German programs.
For NATO, interoperability remains a challenge: although KAAN aims to be an aircraft compatible with Alliance standards, its adoption by a member such as Spain could create separate weapons ecosystems, with different logistics chains, software, and calibers. Some analysts believe that this could fragment the ability to merge systems and coalitions.
But there is also an industrial leverage effect: a Spain-Turkey agreement could generate co-production collaborations, technology transfers, and strengthen the European aerospace sector as a whole. This is redrawing industrial alliances and could push other states to consider alternatives to US platforms.
Finally, this shift shows that southern Europe’s air defense is undergoing major changes, and that players such as Spain are seeking to combine operational capability, strategic independence, and industrial integration.
When and how will Madrid have to decide?
The Spanish Ministry of Defense will have to make a strategic choice in the next 12 to 24 months. The key criteria will be: the technical maturity of the KAAN, delivery guarantees, total cost of ownership, integration into the armed forces, and associated industrial commitments. It will also be necessary to assess the progress of the FCAS program and decide whether the KAAN is only a transitional solution or a long-term pillar.
On the operational side, the first orders will have to include testing phases, training units, and maintenance systems. On the industrial side, contracts for Spanish participation in the production or maintenance of the KAAN must be provided for in order to maximize national benefits.
Strategically, Spain will have to manage its relationship with the United States, NATO, Turkey, and its European partners. Such a choice will not be purely technical but highly political. If the KAAN proves viable, Spain could become a pilot campus for its European integration, paving the way for other European customers or co-developments.
The gamble of a new era in aviation
Spain’s shift towards the Turkish KAAN fighter jet, if confirmed, symbolizes a major turning point in European defense policy: the search for credible alternatives to American giants, the desire for strategic autonomy, and openness to new industrial partnerships. For Madrid, this gamble is both an opportunity—to redefine its air force, modernize its fleet, and revitalize its industry—and a challenge—to control costs, integrate an aircraft still in development, and ensure interoperability within a NATO context.
The road ahead remains winding, but Spain seems determined to no longer settle for a single traditional path. The choice of an aircraft such as the KAAN could herald a silent revolution in European air forces.
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