The creation of the PD-8 engine was a response to several challenges faced by the Russian aviation industry in the second half of the 2010s. The immediate impetus for the project was the need to replace the Ukrainian D-436TP engine used on the Be-200 amphibious aircraft. That engine was produced by the Zaporizhzhia-based “Motor Sich” company, but due to geopolitical changes, a severe deterioration in relations with Ukraine, and sanctions-related risks, its further use became impossible. Without a new power plant, the production of the Be-200 was under threat—the last aircraft of this type was produced in Taganrog in 2021.
Initially, the French-Russian SaM146 engine, already used on the SSJ100, was considered a replacement for the Ukrainian engine on the Be-200. The SaM146 resulted from a partnership between the French company Snecma and the Russian firm NPO Saturn. Its design was based on proven solutions from the widely used CFM56 engine in global civil aviation. The SaM146 provides a thrust of up to 7,900 kgf and has a specific fuel consumption of 0.64 kg/(kgf•h), meeting ICAO noise and emissions standards.
The SaM146 was produced by the PowerJet joint venture in Rybinsk, which received the “hot” section of the engine—the gas generator consisting of the high-pressure compressor, combustion chamber, and high-pressure turbine—from Snecma. UEC-Saturn manufactured the “cold” section: the fan and low-pressure turbine, and performed the final assembly. However, in 2019, the Russian Prosecutor General’s Office warned the Ministry of Industry and Trade (Minpromtorg) about the risks associated with using NATO-country components in the SaM146 engine. Western sanctions made such a choice unsafe for defense contracts. As a result, the idea of re-engining the Be-200 with the SaM146 was abandoned, and the only viable option became the development of a domestic engine with comparable thrust.
At the same time, problems arose with the SSJ100. To To recoup the investments made in the SaM146 project, Snecma refused to reduce the cost of the components it supplied. This increased operating costs for airlines using the Superjet, and Russia incurred losses due to the supplier’s inflexible pricing policy. In 2022, the imposition of sanctions on Russia’s civil aviation sector halted the supply of components from France.
The development timeline for the PD-8, as announced by Minpromtorg to the media, was ambitious from the start. In 2019, the ministry stated that the engine was expected to be ready within five years, with certification anticipated by the end of 2023.
Traditionally, the development of a new aviation gas turbine engine takes at least ten years. The PD-8 became an exception: it was developed in six years. For comparison, the PS-90 engine took 12 years to create, and the PD-14 took ten. This leap was made possible due to several factors, including the following.
Designers at UEC-Saturn leveraged existing groundwork, including that developed during the PD-14 engine project. This reduced the time needed to design key components of the PD-8, particularly the gas generator. The program was given top priority due to sanctions, and one of the key factors that significantly shortened the PD-8’s development time was the use of digital technologies.
UEC-Saturn served as the lead developer and manufacturer. From the very beginning, the development of the PD-8 engine in Rybinsk involved extensive use of modern software-based design methods. Elements of the digital certification strategy were implemented, which involved using digital twin technology and computer modeling to reduce the volume of required physical testing, increase its effectiveness, and accelerate the certification process. Certification reports included the results of computer simulations conducted during virtual tests of both individual components and the engine system as a whole.
The use of digital twins and virtual testing in the early development stages made it possible to minimize the number of costly physical checks. After thoroughly fine-tuning all parameters in a virtual environment, real-world testing was conducted. This approach significantly accelerated the development process and the identification of potential issues. Additionally, automation tools and engineering data management systems were widely used to shorten the time required for design and certification tasks.
Using domestic software platforms CML-Bench® and pSeven Enterprise, engineers carried out a massive number of virtual tests to determine strength loads, temperature regimes, and aerodynamic characteristics, which significantly reduced the need for expensive physical testing. The results of PD-8 computer simulations formed the basis for its certification validation. In the future, this will allow for a substantial reduction in the scope of bench tests needed for new PD-8 engine modifications.
Other companies within the United Engine Corporation (UEC) were also involved in the PD-8 project. The UEC-Aviadvigatel design bureau in Perm developed the combustion chamber, high-pressure turbine, gear unit, central drive, and angled conical gear.
UEC-STAR created the SAU-8 automatic control system, a full-authority digital engine control (FADEC) system with no hydromechanical backup. Its main advantage over a hydromechanical system is the ability to process a much larger number of parameters, enabling optimization of engine performance. UEC-STAR is the only company in Russia with the capabilities for both the development and mass production of fuel supply and control systems for gas turbine engines, including FADEC-type electronic units.
The SAU-8 monitors dozens of parameters—from fuel pressure to clearances between turbine rotors and stators. Its tests included trials at temperatures of 1100°C. The SAU-8 was developed in just one and a half years, using only Russian-made electronic components.
The UEC-UMPO facility in Ufa manufactures the intermediate casing blanks—one of the engine’s largest components—where compressed air is divided into two flows: the outer and inner bypass paths. UEC-UMPO also produces castings for bearing housings and adapter housings for the drive system.
The All-Russian Scientific Research Institute of Aviation Materials (VIAM) developed five innovative cast heat-resistant alloys for the PD-8 in a short time. These were created based on modern mechanical and operational requirements and stand out among Russian counterparts for their optimal combination of manufacturability, strength, and cost.
Mass production of these alloys is carried out at the Kurchatov Institute–VIAM scientific and production complex. The alloys were qualified for use in the most critical and highly loaded gas turbine components. Special attention was given to the VZhM12 alloy for single-crystal turbine blades, which surpasses rhenium-containing nickel alloys in mechanical properties and long-term strength at 1100°C.
VZhM200 alloys for directionally solidified blades and VZhL125 for nozzle vanes are alloyed with hafnium, which increases ductility while maintaining high strength. In VZhL718 and VZhL220, strengthening is achieved through an intermetallic phase based on niobium nickelide (Ni₃Nb), providing high weldability—critically important for casing components. The development and certification of such casting materials in Russia was accomplished for the first time.
The development of external systems for the PD-8 engine was carried out by JSC “Design Bureau ‘Aerospace Systems’” using integrated digital design methods. Engineers used digital twins to precisely position each component, eliminating the need for manual adjustment of wiring harnesses and pipelines on the finished product. This approach accelerated production and reduced the risk of errors. The electrical wiring harnesses and pipelines were designed considering the limited space and strict industry standards. Modern onboard wires with improved insulation and smaller diameters were used, reducing the overall weight of the structure and increasing resistance to overloads.
By using 3D models and CNC machining, they were able to abandon physical templates and speed up the pipeline development process. In areas with high vibration, flexible high-pressure hoses were used. These can withstand temperatures up to 1100°C and pressures up to 280 atmospheres. To protect from heat, the pipelines were covered with thermal insulation. The material chosen for them was the heat-resistant alloy KhN75MBTYU, which is corrosion-resistant.
The PD-8 is built using a classic two-shaft design, ensuring optimal load distribution between components. The outer shaft connects the fan and low-pressure turbine, while the inner shaft connects the compressor and high-pressure turbine. This separation improves performance across various operating modes, reduces vibration, and increases engine lifespan.
The engine’s fan consists of 24 wide-chord titanium blades. Behind it is a three-stage low-pressure compressor, which pre-compresses the air. Next is a seven-stage high-pressure compressor—one more stage than on the SaM146. This stage increased the compression ratio to 28:1, improving fuel efficiency. The first two stages use variable stator vanes to ensure stable operation in all modes.
The straight-through annular combustion chamber, developed by UEC-Aviadvigatel in Perm, features low emissions and high thermal resistance. Its design incorporates solutions from the PD-14 engine, including heat-resistant alloys and coatings. This helped shorten development time without compromising reliability.
The PD-8 nacelle, also designed by UEC-Aviadvigatel based on experience with the PD-14, is 60% made of composite materials, reducing the weight of the powerplant.
The nacelle includes a grid-type thrust reverser, replacing the bucket system used on the SaM146. It deploys faster and quieter, improving braking performance after the aircraft lands. The nacelle is integrated with a flow mixing system, which further reduces noise levels by 5 EPNdB. All auxiliary units—generators, hydraulic pumps, and fuel systems—are placed on the sides of the engine. This reduces the nacelle height and facilitates integration with the aircraft wing.
Production of the nacelle for the PD-8 engine has been organized at the Voronezh Aircraft Manufacturing Company (VASO, a branch of PJSC “Ilyushin”). The flight set includes the fairing, casing, and doors. Non-metal and polymer-composite parts are manufactured based on digital models using high-performance equipment. Components of the PD-8 nacelle and thrust reverser system are produced by the Perm-based “Mashinostroitel” plant.
When designing the import-substituted “Superjet”, the load-bearing structure of the airframe, including the engine mount assemblies and pylons, was largely preserved. According to Alexander Dolotovsky, Deputy General Director of Yakovlev, the aircraft’s powerplant is unified with the SaM146 engine in terms of mounting points. This was done not only to enable convenient replacement of the French-Russian engine on existing aircraft with the PD-8 but also to minimize structural changes to the airframe and reduce the scope of strength and durability testing.
Testing of the PD-8 began in 2021. In May, the first prototype gas generator was installed on a test bench. Bench testing of this critical element of any gas turbine engine took place from May 18 to June 11. UEC specialists achieved stable startups and successful operations at maximum power, confirming the correctness of the design decisions.
By the end of September that year, the second gas generator had been bench tested. The units’ joint operation was tested, and measurements were taken for temperature, pressure, and emission levels. The results confirmed the efficiency of the engine’s hot section. The gas generator was then sent to the CIAM altitude test bench, where real flight conditions were simulated. Simultaneously, the compressor was tested on a separate rig to determine its performance characteristics.
During bench tests of the first PD-8 prototype, the automatic control systems were fine-tuned, and engine startup with transition to idle power was stabilized. Key parameters across all operating modes were recorded, from idle to maximum takeoff power. The testing program included measurements to assess temperature states, structural strength, vibration resistance, and inspections of the air, oil, and fuel systems. Using 500 sensors, data was collected on the condition of parts and assemblies for subsequent analysis of the engine’s overall system performance.
In December 2022, the PD-8 made its first flight, installed under the wing of the Il-76LL flying testbed in place of engine No. 2 (D-30KP-2, inner left). The flight tests evaluated performance across various regimes, including takeoff and cruise. The flights also tested engine integration with the aircraft systems, and operational data such as RPM, pressure, and temperature were recorded along with additional parameters required to validate design decisions and ensure the powerplant’s safe operation.
In October 2023, the PD-8 test was started on an SJ-100 aircraft. Based on the results of both flight and ground tests, the PD-8 was improved, and on March 17, 2025, the first flight of the SJ-100 with the new engines took place. The aircraft was airborne for 40 minutes, reached a speed of 500 km/h, and reached an altitude of 3,000 meters. The engines demonstrated stable performance in both steady and variable conditions. The PD-8’s certification is planned for completion in autumn 2025. The first SJ-100 aircraft with domestically produced engines are expected to be delivered to customers in 2026.
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