Turkey orders sixth prototype of KAAN fighter jet to intensify testing ahead of planned deployment in 2035.
The sixth prototype of the 5th generation KAAN fighter jet was ordered by the SSB (Presidency of Defense Industries) in July 2025, reinforcing a simultaneous testing campaign: wind tunnel, avionics, environmental resistance, and high-speed taxiing. This new prototype completes a strategic plan for six aircraft, each dedicated to specific phases: flight, avionics, and weaponry. The production blocks will follow one after the other: Block 20 with GE F-110 engines from 2028, Block 30 then 40 with TEI-TF35000 engines, scheduled for 2032. This program, initiated in 2010 and accelerated after the withdrawal from the F-35 program, aims to bring together a local industry, offer an autonomous fighter (~100–150 units) at €80–120 million per unit, and target exports—Indonesia is already interested, and Azerbaijan, Pakistan, and Ukraine are in discussions. The KAAN represents a technical, economic, and geopolitical breakthrough for Türkiye, with entry into service planned for 2035.
The strategic context influencing KAAN
The KAAN program was launched in 2010 by the SSB to design a 5th generation fighter to replace the aging F-16 fleet. Türkiye’s exclusion from the F-35 program in 2019, due to its purchase of the Russian S-400 system, resulted in an estimated loss of $20 billion, but also freed up resources and motivation to strengthen a sovereign industry. Replacing the fighter in the select circle of countries with stealth aviation (United States, China, Russia) is a strategic lever: the KAAN aims to achieve capabilities comparable to the F-22, F-35, J-20, and Su-57.
The effort is aligned with a proactive geopolitical doctrine: establishing regional influence (Middle East, Central Asia, Africa), reducing Western dependence, and supporting relations within NATO. The successor to the F-35—both technologically and politically—is essential to consolidating this position. This agenda is consistent with the goal of strategic autonomy, both military and industrial. The approach is accompanied by massive investments in local industrial partners (TAI, TEI, Aselsan, Roketsan), involving more than 10,000 engineers and a projected budget of between €15 and €20 billion by 2035. These elements highlight the program’s structural framework—at the crossroads of technological, political, and economic ambitions.
Details of the sixth KAAN prototype and planned test phases
The order for the sixth KAAN prototype in July 2025 marks a milestone in the program’s ramp-up. This prototype is intended to accelerate parallel testing, avoiding bottlenecks associated with the limited availability of previous platforms. It is part of a functional decoupling approach: each aircraft is assigned to a specific campaign—avionics validation, high-speed maneuvers, structural testing, environmental testing, and certification of onboard systems.
The sixth prototype is being used for wind tunnel testing, which is crucial for validating aerodynamic performance at different speeds and angles of attack. TUSAŞ’s transonic tunnels can simulate speeds close to Mach 2 under controlled conditions. The KAAN fuselage is being studied using 1:7 and then 1:3 scale models, with measurements of lift, drag, and vibration behavior.
At the same time, environmental stress tests are conducted in climatic chambers simulating extreme temperatures ranging from −55°C to +60°C, with humidity cycles and dust exposure. These simulations anticipate operational deployments in desert, continental, and polar environments.
The program also includes high-speed taxi tests (High-Speed Taxi Test), which validate the aircraft’s directional stability on the runway, the performance of the carbon-ceramic brakes, and the strength of the landing gear. These taxi tests are conducted at speeds of up to 250 km/h without takeoff, with a focus on avionics responses in real flight conditions.
Finally, the validation of the onboard avionics systems (inertial navigation, AESA radar, data links, electronic countermeasures) involves an integrated test bench simulating multi-source interference, internal failures, and electromagnetic attacks. These tests are a critical phase, particularly for the validation of the mission management system (Mission Computer).
The addition of this prototype to the development chain will enable the program to remain on a tight schedule while complying with NATO certification standards. It will help stabilize the margins for maneuver for future supersonic flight phases, live weapon testing, and tests with operational pilots.
A domestically produced engine: a critical milestone in the KAAN program
One of the most sensitive pillars of the KAAN program is propulsion independence. Currently, the prototypes are equipped with American-made General Electric F110-GE-129 engines, which are already used on Turkish F-16s. These afterburning turbojet engines produce a maximum thrust of 131 kilonewtons each, enabling the KAAN to reach an estimated speed of Mach 1.8 to 2, or approximately 2,200 km/h at high altitude.
However, the use of this foreign engine is a temporary solution. The real ambition of the program is to integrate a domestic engine, currently under development under the name TEI-TF6000 for basic testing, and TEI-TF35000 for the final twin-spool version, dedicated to supersonic flight with afterburner. This engine is being developed by TEI (Tusaş Engine Industries), a company formed through a partnership between Turkish Aerospace Industries, General Electric, and the Turkish government.
The TEI-TF35000 engine aims to deliver a unit thrust of 159 kilonewtons, representing a performance gain of nearly 20% over the F110, while incorporating high-temperature-resistant materials (nickel-based superalloys, reinforced ceramics) and monobloc blade compressors. Development has been in the static engine test stage since 2023, with flight test campaigns planned to begin in 2027.
The design is based on a modular architecture: twin-spool, twin-flow, with afterburner, FADEC control, and variable intake. The goal is to achieve a thrust-to-weight ratio greater than 10:1, which would place it in the same category as engines comparable to the F119 in the F-22 or the Saturn AL-41F1 in the Su-57. The engine will also have to meet acoustic and thermal stealth requirements, in particular through partial cooling of the exhaust gases and specific treatment of the nozzles to reduce the infrared signature.
In addition to performance, the indigenous engine would secure the supply chain, avoid regulatory dependencies (US ITAR licenses), and reduce operating costs. The target unit cost would be $4 to $5 million, compared to $7 to $8 million for an imported F110. Turkey hopes to produce 40 engines per year locally once industrial production begins in 2030, with a target operational life of 4,000 to 6,000 hours, or 15 to 20 years in standard military use.
The integration of this engine into the future Block 30 (around 2032) and Block 40 (by 2035) series represents a strategic turning point for the program. It will determine not only technological autonomy, but also export viability, as a national engine would make it possible to avoid export restrictions imposed by foreign suppliers. It could also make the TEI engine an export product for other regional, civil, or military aircraft platforms.
Performance and technical capabilities of the KAAN fighter
The KAAN was designed as a 5th generation fighter aircraft, combining radar stealth, operational versatility, advanced avionics, and supersonic capabilities. The available technical data reveals a twin-engine aircraft with a length of 21 meters, a wingspan of 14 meters, and an estimated maximum takeoff weight of 27 tons. It is equipped with a retractable tricycle landing gear and an internal weapons bay designed to preserve stealth.
At top speed, the KAAN should reach Mach 1.8 to 2 (approximately 2,200 km/h at high altitude) thanks to its twin engines. The planned range in combat configuration is over 1,100 kilometers, with a range of over 1,500 kilometers with additional fuel tanks. The aircraft should also have in-flight refueling capability via a rigid or flexible boom.
In terms of maneuverability, Turkish Aerospace Industries engineers are aiming for agility equivalent to the F-22. The design includes large movable surfaces (control surfaces and slanted fins), a quadruple redundant digital flight control system, and electromechanical actuators integrated into the wing to minimize latency. The announced instantaneous turn rate is greater than 20 degrees per second in transonic flight.
The avionics suite includes an AESA active electronically scanned radar produced by Aselsan, an IRST infrared optronic pod, a modular electronic warfare suite, and a data link system compatible with NATO standards (Link 16, MADL). The cockpit environment is fully digital, with a large-format HUD display, voice commands, a touchscreen interface, and AI-assisted piloting.
The internal cargo bay can carry medium- and long-range air-to-air missiles (Gökdoğan, Bozdoğan), GPS-guided air-to-ground missiles, and laser-guided bombs. The internal payload is estimated at 2,500 kg, supplemented by external hardpoints that can increase the total to 10 tons in non-stealth configuration. This compromise allows the KAAN to perform air superiority, ground attack, and strategic strike missions with a low radar signature when configured for infiltration.
In terms of radar signature, although the exact values remain classified, several sources estimate the radar cross section (RCS) to be less than 0.01 m² in the X band. This would place the KAAN on a par with the F-35 or slightly above the F-22, while remaining well below 4++ generation fighters (Typhoon, Rafale, Su-35).
Finally, stealth characteristics are enhanced by the use of radar-absorbing composite materials (RAM), a pronounced swept-back aerodynamic profile, and a design with no external protrusions (antenna, sensors, weapon load) on the initial operational configurations.
These technical specifications position the KAAN as an advanced multi-role fighter capable of performing a variety of missions in contested environments, with enhanced survivability against modern ground-to-air defenses.
KAAN production schedule and gradual integration
The KAAN program is based on successive block deployment, a method that allows capabilities to be validated gradually while industrial development continues. This phased schedule allows for a controlled ramp-up and reduction of technological risks by limiting simultaneous changes on the same platform.
The first prototype made a 13-minute maiden flight in February 2024 at low altitude, with the landing gear extended and a restricted flight envelope. This test, carried out at Mürted Air Base (near Ankara), was presented as a major milestone, two years ahead of the initial schedule. It validated the airframe’s behavior, flight controls, onboard sensor response, and avionics module synchronization.
Development is now following a plan divided into four main blocks:
- Block 10 (2024–2026): development prototypes. Test flights, aerodynamic validation, avionics testing.
- Block 20 (2027–2029): first limited series equipped with F110 engines. Introduction into squadrons for operational testing within the armed forces.
- Block 30 (2030–2033): transition to TEI-TF35000 engines. Enhanced combat capabilities (electronic warfare, tactical data link).
- Block 40 (2034–2035): fully integrated version, national engine, optimal stealth capabilities, full payload.
Industrial production is scheduled to start in small volumes in 2028, with a target rate of 10 to 12 aircraft per year from 2030. The official goal is to deliver between 100 and 150 aircraft to the Türk Hava Kuvvetleri (THK) by 2035, depending on budgetary requirements and the level of industrialization of the indigenous engine.
Integration into combat units will be gradual, starting with squadrons currently equipped with F-16s, beginning with those assigned to national air defense. Pilots will be trained on simulators starting in 2026, in parallel with a specific operational conversion program. Virtual test benches, incorporating NATO scenarios, are also being deployed to support this ramp-up in capacity.
This plan leaves open the possibility of partial integration into Turkish C4ISR command systems as early as the Block 20 version. The entire process, from flight testing to full operational capability (FOC), is estimated to take 10 to 12 years. The SSB’s objective remains full service entry by 2035, with all critical components (engine, radar, electronic warfare system, mission suite) sourced from the national industrial base.
This realistic but ambitious schedule is key to the program’s credibility with its international partners and will determine its future commercial prospects.
War Wings Daily is an independant magazine.