- Turkish Airlines and Boeing: Balancing Fleet Expansion, Technology, and Risk
- Critical Issues in LEAP-1B Engines
- The TF35000 Engine: The Heart of KAAN
- Engine Options: From Foreign to Domestic
Dear Readers,
The year 2025 has become a critical turning point for Turkish Airlines (THY). In a move that captured global attention within the aviation world, the airline signed a massive deal with Boeing for a total of 225 aircraft.
Details of the Order
THY placed an order for 75 Boeing 787-9 and 787-10 wide-body aircraft — 50 firm and 25 optional. In the narrow-body segment, negotiations have been completed for 150 Boeing 737-8 / 737-10 MAX aircraft, of which 100 are firm and 50 are optional. However, these will be finalised once the engine contracts are settled. Deliveries are planned between 2029 and 2034.
LEAP-1B Engines: Technology and Challenges
The 737 MAX family will be powered by LEAP-1B engines developed by CFM International. These engines offer a 15% improvement in fuel efficiency compared to the previous generation, operate more quietly, and have lower emissions. Composite fan blades and advanced materials provide significant advantages in modern aviation.
However, despite these technological strengths, LEAP-1B engines also come with certain challenges and risks:
- Compressor Stall and Pressure Fluctuations: Incidents resembling compressor stalls have been observed in the high-pressure compressor section. Wear has been detected in the “spring finger housing” component above the No.3 bearing; this can lead to aborted take-offs or return-to-base events.
- Smoke and Odour Issues: In 2023, several Southwest Airlines 737 MAX aircraft experienced cabin and cockpit smoke following bird strikes that caused engine oil to contact hot components.
- Short Time-on-Wing / Early Maintenance Cycles: Operators report that expected service intervals are not being achieved; maintenance cycles vary between 2,000 and 6,000 flight cycles.
- Material and Coating Problems: Peeling and thermal degradation have been reported in coatings used in high-temperature regions.
- Production and Supply Quality: Tolerance deviations and quality control problems have been identified in turbine segments, seals, and other critical components.
Real-World Incidents and Operational Responses
- Southwest Airlines (2023): Following a bird strike, the engine fan blades were damaged; engine oil contacted hot surfaces, causing smoke in the cabin. The aircraft diverted safely, with no injuries reported.
- SpiceJet, India: An oil filter bypass alert triggered a return to base, followed by DGCA-ordered technical inspections.
These examples show that while such engine system issues may not directly threaten flight safety, they demand vigilant operational and maintenance management.
Grounding and Anti-Icing Problems
Temporary groundings occurred in test or undelivered 737 MAX aircraft due to defects in the “low-pressure turbine disk.” The anti-icing system at the engine inlets has also shown occasional overheating, delaying MAX-7 and MAX-10 certifications. Boeing is still working on a permanent fix.
Production, Software, and Control Systems
Manufacturing errors, such as door plugs installed with missing bolts, have led to in-flight depressurisation incidents.
The MCAS and stabiliser trim systems previously caused accidents due to software issues, but these systems have since been improved with additional safeguards.
Regulatory authorities like the FAA and EASA closely monitor these issues, issuing corrective safety directives where necessary.
THY’s Strategic Vision
According to THY’s 2023–2033 strategic plan, the airline aims to modernise its fleet, expand capacity, and retire older aircraft with a total of 355 new orders. The Boeing deal strengthens the fleet’s modernisation and increases Boeing’s share in the fleet mix. The 2029–2034 deliveries will be key milestones in realising this vision.
THY’s agreement with Boeing is a bold investment and a powerful strategic step. However, engine issues, manufacturing errors, and software risks — while not posing direct threats to flight safety — are important factors to consider in operational planning, maintenance costs, and fleet management.
In aviation, success is measured by the ability to manage risk, maintain a strong safety culture, and use technology wisely. If THY gets this balance right, it could become the regional leader in both fleet capacity and technological capability by the 2030s.
But one must remember: big orders bring big responsibilities. Delivery timelines, engine reliability, production quality, and maintenance management will be the key elements that determine the success of THY’s Boeing initiative.
KAAN: Turkey’s Leap Towards Airborne Independence
Turkey’s defence industry is at a historic turning point. The National Combat Aircraft (KAAN) project represents a milestone on the road to technological sovereignty. This fifth-generation multirole fighter jet will push the boundaries of Turkish engineering in the skies. But behind every powerful aircraft lies an engine — and for KAAN, that power source is the motor system.
Engine Options: From Foreign to Domestic
The choice of engine will define KAAN’s future. Two options are currently on the table:
1. General Electric F110 (Initial Phase)
- The first prototypes use the proven F110 engines, also utilised in F-16s, to provide reliability and performance in early flight tests.
- Advantages: Proven technology, established supply chain, rapid integration.
- Disadvantages: Foreign dependency and lack of long-term strategic autonomy.
2. TEI TF35000 (Domestic Development)
Turkey’s proudly domestic TF35000 engine, delivering 35,000 pounds of thrust, has been designed entirely with KAAN’s fifth-generation requirements in mind. Developed jointly by TUSAŞ and TRMOTOR, it targets prototype production by the end of 2025, test flights in 2026, and full integration into KAAN by 2032.
- Advantages: Fully domestic production, strategic independence, and long-term technological accumulation.
- Challenges: Complex testing and optimisation processes; initial flights may exhibit unexpected performance variations.
“The TF35000 engine is not just a power unit — it is a symbol of Turkey’s determination to achieve independence in the skies. It embodies the imagination and perseverance of our engineers.”
Engine Technology Overview
The TEI TF35000 is being developed to meet the demands of modern fighter jet propulsion, focusing on high thrust-to-weight ratio, fuel efficiency, and reduced radar signature. Experience gained from the TF6000 and TF10000 engines used in ANKA-III and KIZILELMA provides a significant advantage in the design and development phases.
- Thrust and Performance: With 35,000 pounds of thrust, it will support KAAN in supersonic flight and high-manoeuvrability missions.
- Efficiency: Advanced turbofan technology optimises fuel consumption, enhancing long-range mission capability.
- Integration: Designed for full compatibility with KAAN’s radar and weapons systems, directly impacting operational safety and performance.
“An engine is not just a component — it is the heart of a fighter jet. The success of the TF35000 will determine KAAN’s destiny in the skies.”
Prototypes and Testing Phases
Under the KAAN project, six prototypes will be produced, each dedicated to specific test objectives:
- P0 Prototype (2024): Completed its first flight on 21 February, reaching 8,000 feet and 230 knots, focusing on basic aerodynamic and structural testing.
- P1 Prototype (2025): Will test avionics systems, sensor integration, and mission simulations.
- P2–P6 Prototypes (2026–2028): Will undergo weapons integration, radar testing, performance optimisation, and engine validation.
Each prototype ensures comprehensive testing and early detection of potential issues. Engine performance verification will be particularly critical from the P2 stage onwards.
The 2028 Target
- End of 2025: Prototype TF35000 engine production
- 2026: Initial test flights
- 2028: Delivery of prototypes to the Turkish Air Force
- 2032: Full integration of the TF35000 into KAAN
“The year 2028 will mark a symbolic milestone in Turkey’s quest for defence industry independence.”
Turkish Engineering in the Skies
The KAAN project embodies Turkey’s strategic vision. From engine technology to avionics, weapons integration to aerodynamics, every detail reflects the maturity of Turkish engineering.
Each flight will represent a new step on Turkey’s path to independence. Each prototype will be proof of the patience and vision of our engineers. The TF35000 engine, as KAAN’s heart, stands at the centre of this journey.
“KAAN is the pride of Turkish engineering in the skies — and its engine is the heartbeat that sets its rhythm.”
Wishing all pilots and ground crews a safe and peaceful week ahead.
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