Türkiye’s ambition to develop an indigenous engine for its fifth-generation KAAN stealth fighter is approaching a critical stage, with the TF-35000 programme expected to move from design development towards full-engine ground testing. The proposed powerplant, designed to produce 35,000 pounds-force of afterburning thrust, could eventually reduce Ankara’s dependence on foreign propulsion technology and give the country greater control over the fighter’s maintenance, upgrades and export potential.
Reports suggesting a November 2026 ground-test window have brought renewed attention to the programme. A successful test of a complete engine would represent an important milestone, allowing Turkish engineers to evaluate the integrated performance of the compressor, combustion chamber, turbine and digital engine-control systems under operating conditions.
However, the reported November testing schedule has not yet been independently confirmed as a completed or fully authorised engine run. Publicly available information also does not establish claims that the TF-35000 could deliver approximately 80 percent more power at high altitude. Such an assessment would require comparative performance data under equivalent operating conditions.
Nevertheless, the programme represents one of Türkiye’s most consequential efforts to develop an independent defence-industrial capability. The engine is intended to power later production versions of KAAN, while the fighter’s initial development and early operational aircraft will rely on American-made General Electric F110-GE-129 engines.
The TF-35000 is a low-bypass afterburning turbofan designed to deliver approximately 35,000 pounds-force, equivalent to 156 kilonewtons, of thrust. Its target places it in the same broad thrust category as the F119 engine powering the American F-22 Raptor.
Compared with the approximately 29,000–31,000 pounds-force generally associated with the F110, the Turkish engine’s target represents a nominal thrust increase of around 13–21 percent, depending on the reference rating used.
That additional thrust could improve KAAN’s acceleration, climb performance and ability to carry mission equipment without sacrificing as much performance margin. However, actual aircraft performance will depend on installed thrust, engine weight, fuel consumption, aerodynamic drag and operating conditions.
The TF-35000 is also expected to support Türkiye’s ambition to develop a fighter capable of sustained supersonic flight without afterburner, commonly known as supercruise. Achieving that capability will require sufficient dry thrust and aerodynamic efficiency, rather than relying exclusively on the engine’s maximum afterburning rating.
Publicly available dry-thrust and specific fuel-consumption figures remain insufficient to establish whether KAAN will achieve operational supercruise or how its range and endurance will compare with competing fighters.
Türkiye’s decision to develop an indigenous engine does not prevent the KAAN programme from advancing in the meantime. The fighter’s first demonstrator, known as P0, completed its initial flights in February and May 2024 using F110 engines.
Those flights established an initial airborne testing foundation, allowing engineers to examine basic flight characteristics and gradually expand the aircraft’s development programme.
The more representative P1 prototype has subsequently progressed through system checks and low-speed taxi activities. High-speed taxi trials and associated ground-clearance procedures are important steps towards its first flight.
Turkish Aerospace Industries (TAI) chief executive Mehmet Demiroğlu has indicated that the programme aims to fly P1 before the end of 2026. The aircraft’s first flight would provide an important opportunity to evaluate the revised airframe, aerodynamic configuration and integrated flight-control systems under actual flight conditions.
A second prototype, P2, is also progressing, while the broader development plan envisages six test aircraft. Operating several prototypes would allow Turkish engineers to conduct flight-control, avionics, radar and mission-system testing in parallel.
The newer prototypes incorporate changes to the air intakes, aerodynamics and landing gear compared with the original demonstrator. The aircraft is also being developed around an advanced sensor and weapons architecture, including an ASELSAN MURAD active electronically scanned array radar and internal weapons bays.
These systems will be essential to establishing KAAN as an operational combat aircraft. Its eventual combat readiness will depend not only on flight performance but also on radar integration, weapons certification, electronic warfare capabilities and the reliability of its propulsion system.
The early aircraft will continue to use the American F110-GE-129, an engine family already familiar to Türkiye through its F-16 fleet. This provides a relatively established propulsion solution while the domestic engine undergoes development and qualification.
A 2026 United States notification covering approximately 80 additional F110 engines provides a procurement pathway for supporting the initial KAAN programme. Since each fighter requires two engines, 80 engines theoretically represent 40 aircraft sets before accounting for spares, replacement requirements and engines allocated to testing.
The availability of these engines will therefore influence how quickly Türkiye can produce, test and sustain its first KAAN aircraft.
Demiroğlu has placed the expected introduction of the TF-35000-powered KAAN around 2033. The timeline gives Turkish engineers several years to move from prototype testing towards endurance qualification, flight integration and serial manufacturing.
Initial Block 10 deliveries are targeted for late 2028 or early 2029, allowing the Turkish Air Force to begin introducing the aircraft before the domestic engine becomes operationally available.
The TF-35000 programme is being developed through Türkiye’s defence-industrial ecosystem, with Turkish Engine Industries (TEI) and TRMOTOR playing important roles.
TEI General Manager Mahmut Faruk Akşit identified the critical design review as a milestone reached around February 2026. The review establishes the engineering baseline against which prototype manufacturing, testing and subsequent design modifications can be assessed.
The programme has also benefited from Türkiye’s experience with smaller indigenous engines, including the TF6000 and TF10000. However, developing a 35,000-pound-class fighter engine presents substantially greater engineering challenges.
The most demanding components are likely to be found in the high-temperature sections of the engine, particularly the turbine blades and associated cooling systems.
Advanced superalloys, single-crystal manufacturing techniques and thermal barrier coatings are essential for maintaining structural integrity under extreme temperatures and repeated operating cycles. Compressor stability, combustion efficiency and turbine durability will also determine whether the engine can deliver reliable performance over its operational life.
A successful first ground run would demonstrate that the major engine components can operate together. It would not, however, establish that the engine is ready for installation in a fighter.
Further testing would be required to assess endurance, thermal cycling, vibration, fuel consumption and performance across different power settings. Engineers would also need to establish whether the engine can maintain stable operation during rapid changes in airflow and manoeuvres.
Engine integration introduces additional challenges involving inlet compatibility, mounting loads, exhaust geometry, cooling and digital flight-control coordination.
The distinction is important because a powerplant that performs successfully on a test stand must still demonstrate reliable operation when installed inside an aircraft operating across a demanding flight envelope.
TEI’s organisational consolidation and the development of a domestic manufacturing supply chain are intended to strengthen the country’s ability to manage these challenges. Ultimately, the programme’s success will depend on repeatable production quality and the ability to maintain engines without prolonged delays.
KAAN’s development is also acquiring international significance following Indonesia’s commitment to purchase 48 aircraft.
The agreement offers Türkiye an opportunity to establish the fighter in Southeast Asia, a region where military modernisation, maritime security concerns and strategic competition are increasing demand for advanced combat aircraft.
Reports have valued the Indonesian package at approximately US$10 billion–US$15 billion, although the precise commercial structure and delivery arrangements remain subject to the programme’s implementation.
Indonesia’s preference for Turkish propulsion gives the TF-35000 additional importance. An aircraft powered by American F110 engines could involve additional United States export approvals and restrictions, while a domestically powered configuration could provide Ankara with greater flexibility over engine supply, maintenance and future upgrades.
However, indigenous propulsion alone would not make the entire aircraft independent of foreign technology. Radar components, electronic systems, materials and other subsystems may still involve international suppliers and export-control requirements.
For Indonesia, the timing of engine qualification will be particularly important. Airframe deliveries, pilot training, maintenance infrastructure and spare-parts planning all depend on the availability of a clearly defined operational configuration.
A delay in the TF-35000 programme could therefore complicate the transition towards Turkish-powered aircraft, even if KAAN’s airframe development continues according to schedule.
Türkiye is also pursuing a separate high-thrust turbofan development programme known as GÜÇHAN.
The Ministry of National Defence’s research and development centre unveiled the engine at SAHA EXPO in May 2026. Its reported afterburning thrust target of 42,000 pounds-force places it above the TF-35000 in nominal thrust and approaches the thrust category of the F-35’s F135 engine.
Published specifications include a maximum diameter of approximately 46.5 inches, airflow of 420 pounds per second and a bypass ratio of 0.68.
Defence Minister Yaşar Güler and ministry research and development director Nilüfer Kuzulu have described the development of six prototypes. The ministry has also highlighted domestically designed and manufactured single-crystal turbine blades.
Qualification and calibration testing were planned for 2026, although the precise testing timetable and operational maturity remain unclear.
Unlike the TF-35000, which has a defined role in later KAAN configurations, GÜÇHAN has not been assigned a specific aircraft platform. Its immediate significance lies in expanding Türkiye’s experience in advanced turbine materials, manufacturing and high-thrust propulsion technologies.
Integrating GÜÇHAN into KAAN would require substantial engineering assessments. Its higher thrust target does not automatically make it suitable for the fighter, since engine diameter, airflow, weight, mounting requirements and exhaust characteristics must match the aircraft’s design.
The two programmes therefore represent complementary industrial investments rather than interchangeable engines for the same aircraft.
For Ankara, the strategic objective extends beyond producing a fighter with higher thrust. Domestic propulsion could give Türkiye greater control over engine maintenance, overhaul, replacement components and future performance upgrades, reducing exposure to foreign supply restrictions.
That autonomy, however, will depend on the ability to manufacture reliable engines in sufficient numbers and return them to service quickly after maintenance.
A documented TF-35000 ground run would be an important step towards that objective. But the decisive milestones will be endurance qualification, successful aircraft integration, flight testing and the establishment of a sustainable production and maintenance system.
If Türkiye can achieve those targets around the beginning of the next decade, KAAN could gradually transition from an American-powered development aircraft into a domestically powered fifth-generation fighter, strengthening Ankara’s defence-industrial position and giving Indonesia a clearer pathway towards operating Turkish-built combat aircraft.
