Engines used in different fighters

[Manticore]

The aim is to collect specs and possible pictures of different engines


How Jet Engines are made?

Background
The jet engine is the power plant of today's jet aircraft, producing not only the thrust that propels the aircraft but also the power that fuels many of the aircraft's other systems.

Jet engines operate according to Newton's third law of motion, which states that every force acting on a body produces an equal and opposite force. The jet engine works by drawing in some of the air through which the aircraft is moving, compressing it, combining it with fuel and heating it, and finally ejecting the ensuing gas with such force that the plane is propelled forward. The power produced by such engines is expressed in terms of pounds of thrust, a term that refers to the number of pounds the engine can move.

The jet engine, like many technological innovations, took a long time to progress from concept to design to execution. The first attempts to transcend the traditional piston engine were actually modifications of that engine, both heavy and complex. The turbine design was introduced in 1921, and it and the other basic components of the modern jet engine were present in a design for which a Royal Air Force lieutenant named Frank Whittle received an English patent in 1930. Although testing on Whittle's engine began in 1937, it did not fly successfully until 1941. Across the English Channel in a Germany rushing to arm itself for World War II, similar but entirely separate work had begun with a 1935 jet engine patent issued to Hans von Ohain. Four years later, a team of German engineers led by Dr. Max Hahn achieved success, conducting the first entirely jet-powered flight in history. Upon achieving success with the Whittle engine in 1941, the British promptly shipped a prototype to their allies in the United States, where General Electric immediately began producing copies. The first American jet engine, produced by G.E., took flight in a plane constructed by Bell Aircraft late in 1942. Although use of jets was somewhat limited during World War II, by the end of the war all three countries had begun to utilize elite squadrons of jet-powered fighter planes.

Today's commercial engines, up to eleven feet in diameter and twelve feet long, can weigh more than 10,000 pounds and produce more than 100,000 pounds of thrust.



Design
A jet engine is contained within a cowling, an extermal casing that opens outward, somewhat like a rounded automobile hood, to permit inspection and repair of the interior components. Attached to each engine (a typical 747 uses four) is a pylon, a metal arm that joins the engine to the wing of the plane. Through pumps and feed tubes in the pylons, fuel is relayed from wing tanks to the engine, and the electrical and hydraulic power generated by the engine is then routed back to the aircraft through wires and pipes also contained in the pylons.

At the very front of the engine, a fan helps to increase the flow of air into the engine's first compartment, the compressor. As the fan drives air into it, the compressor—a metal cylinder that gradually widens from front to rear—subjects the incoming air to increasing pressure. To accelerate the progress of the air through the engine, the compressor is fitted with blades that rotate like simple household fans. In the incredibly brief time it takes air to reach the inner end of a typical compressor, it has been squeezed into a space 20 times smaller than the intake aperture.




The parts of a jet engine—they can number 25,000—are made in various ways. The fan blade is made by shaping molten titanium in a hot press. When removed, each blade skin is welded to a mate, and the hollow cavity in the center is filled with a titanium honeycomb. The turbine disc is made by powder metallurgy, while the compressor blades and the combustion chamber are both made by casting. (Pic 1)

Expanding as it leaves the high-pressure compressor, the air enters the combustor, an interior engine cylinder in which the air will be mixed with fuel and burned. The combustion chamber is actually a ring, shaped something like a car's air filter. The air that passes through this ring as it exits the compressor is ignited, while another, larger stream of air merely passes through the center of the ring without being bumed. A third stream of air being released from the compressor is passed outside the combustion chamber to cool it.

As the air from the compressor mixes with fuel and ignites in the combustor to produce an incredibly hot volume of gas, some of that gas leaves the engine through the exhaust system, while another, smaller portion is routed into the engine's turbine. The turbine is a set of fans that extend from the same shaft which, further forward in the jet engine, rotates the compressor blades. Its job is to extract enough energy from the hot gases leaving the combustor to power the compressor shaft. In some models, the turbine is also used to generate power for other components of the plane. Because the turbine is subjected to intense heat, each blade has labyrinthine airways cut into it. Cool air from the compressor is routed through these passages, enabling the turbine to function in gas streams whose temperature is higher than the melting point of the alloy from which it is made.

The bulk of the gas that leaves the combustor, however, does so through the exhaust system, which must be shaped very carefully to insure proper engine performance. Planes flying beneath the speed of sound are equipped with exhaust systems that taper toward their ends; those capable of supersonic travel require exhaust systems that flare at the end but that can also be narrowed to permit the slower speeds desirable for landing. The exhaust system consists of an outer duct, which transmits the cooling air that has been passed along the outside of the combustor, and a narrower inner duct, which carries the burning gases that have been pumped through the combustor. Between these two ducts is a thrust reverser, the mechanism that can close off the outer duct to prevent the unheated air from leaving the engine through the exhaust system. Pilots engage reverse thrust when they wish to slow the aircraft.




Raw Materials
Strong, lightweight, corrosion-resistant, thermally stable components are essential to the viability of any aircraft design, and certain materials have been developed to provide these and other desirable traits. Titanium, first created in sufficiently pure form for commercial use during the 1950s, is utilized in the most critical engine components. While it is very difficult to shape, its extreme hardness renders it strong when subjected to intense heat. To improve its malleability titanium is often alloyed with other metals such as nickel and aluminum. All three metals are prized by the aerospace industry because of their relatively high strength/weight ratio.



The intake fan at the front of the engine must be extremely strong so that it doesn't fracture when large birds and other debris are sucked into its blades; it is thus made of a titanium alloy. The intermediate compressor is made from aluminum, while the high pressure section nearer the intense heat of the combustor is made of nickel and titanium alloys better able to withstand extreme temperatures. The combustion chamber is also made of nickel and titanium alloys, and the turbine blades, which must endure the most intense heat of the engine, consist of nickel-titanium-aluminum alloys. Often, both the combustion chamber and the turbine receive special ceramic coatings that better enable them to resist heat. The inner duct of the exhaust system is crafted from titanium, while the outer exhaust duct is made from composites—synthetic fibers held together with resins. Although fiberglass was used for years, it is now being supplanted by Kevlar, which is even lighter and stronger. The thrust reverser consists of titanium alloy.





The Manufacturing

Process
Building and assembling the components of a jet engine takes about two years, after a design and testing period that can take up to five years for each model. The research and development phase is so protracted because the engines are so complex: a standard Boeing 747 engine, for example, contains almost 25,000 parts.



Building components


Fan Blade
1 In jet engine manufacture, the various parts are made individually as part of subassemblies; the subassemblies then come together to form the whole engine. One such part is the fan blade, situated at the front of the engine. Each fan blade consists of two blade skins produced by shaping molten titanium in a hot press. When removed, each blade skin is welded to a mate, with a hollow cavity in the center. To increase the strength of the final product, this cavity is filled with a titanium honeycomb.


Compressor disc
2 The disc, the solid core to which the blades of the compressor are attached, resembles a big, notched wheel. It must be extremely strong and free of even minute imperfections, as these could easily develop into fractures under the tremendous stress of engine operation. For a long time, the most popular way to manufacture the disc entailed machine-cutting a metal blank into a rough approximation of the desired shape, then heating and stamping it to precise specifications (in addition to rendering the metal malleable, heat also helps to fuse hairline cracks). Today, however, a more sophisticated method of producing discs is being used by more and more manufacturers. Called powder metallurgy, it consists of pouring molten metal onto a rapidly rotating turntable that breaks the metal into millions of microscopic droplets that are flung back up almost immediately due to the table's spinning.

Turbine blades are made by forming wax copies of the blades and then immersing the copies in a ceramic slurry bath. After each copy is heated to harden the ceramic and melt the wax, molten metal is poured into the hollow left by the melted wax. A jet engine works by sucking air into one end, compressing it, mixing it with fuel and burning it in the combustion chamber, and then expelling it with great force out the exhaust system. (Pic 2)

As they leave the table, the droplets' temperature suddenly plummets (by roughly 2,120 degrees Fahrenheit—1,000 degrees Celsius—in half a second), causing them to solidify and form a fine-grained metal powder. The resulting powder is very pure because it solidifies too quickly to pick up contaminants.




3 In the next step, the powder is packed into a forming case and put into a vacuum. Vibrated, the powder sifts down until it is tightly packed at the bottom of the case; the vacuum guarantees that no air pockets develop. The case is then sealed and heated under high pressure (about 25,000 pounds per square inch). This combination of heat and pressure fuses the metal particles into a disc. The disc is then shaped on a large cutting machine and bolted to the fan blades.



Compressor blades
4 Casting, an extremely old method, is still used to form the compressor blades. In this process, the alloy from which the blades will be formed is poured into a ceramic mold, heated in a furnace, and cooled. When the mold is broken off, the blades are machined to their final shape.



Combustion chamber
5 Combustion chambers must blend air and fuel in a small space and work for prolonged periods in extreme heat. To accomplish this, titanium is alloyed to increase its ductility—its ability to formed into shapes. It is then heated before being poured into several discrete, and very complex, segment molds. The sections are removed from their molds, allowed to cool, and welded together before being mounted on the engine.

A jet engine is mounted to the airplane wing with a pylon. The pylon (and the wing) must be very strong, since an engine can weigh up to 10,000 pounds. (Pic 3)




Turbine disc and blades
6 The turbine disc is formed by the same powder metallurgy process used to create the compressor disc. Turbine blades, however, are made by a somewhat different method than that used to form compressor blades, because they are subjected to even greater stress due to the intense heat of the combustor that lies just in front of them. First, copies of the blades are formed by pouring wax into metal molds. Once each wax shape has set, it is removed from the mold and immersed in a ceramic slurry bath, forming a ceramic coating about .25-inch (.63-centimeter) thick. Each cluster is then heated to harden the ceramic and melt the wax. Molten metal is now poured into the hollow left by the melted wax. The internal air cooling passages within each blade are also formed during this stage of production.




7 The metal grains in the blade are now aligned parallel to the blade by a process called directional solidifying. The grain direction is important because the turbine blades are subjected to so much stress; if the grains are aligned correctly, the blade is much less likely to fracture. The solidifying process takes place in computer-controlled ovens in which the blades are carefully heated according to precise specifications. The metal grains assume the correct configuration as they cool following their removal from the ovens.




8 The next and final stages in preparing turbine blades are machine-shaping and either laser drilling or spark erosion. First, the blade is honed to the final, desired shape through a machining process. Next, parallel lines of tiny holes are formed in each blade as a supplement to the interior cooling passageways. The holes are formed by either a small laser beam or by spark erosion, in which carefully controlled sparks are permitted to eat holes in the blade.




Exhaust system
9 The inner duct and the afterburners of the exhaust system are molded from titanium, while the outer duct and the nacelle (the engine casing) are formed from Kevlar. After these three components have been welded into a subassembly, the entire engine is ready to be put together.




Final assembly
10 Engines are constructed by manually combining the various subassemblies and accessories. An engine is typically built in a vertical position from the aft end forward, on a fixture that will allow the operator to manipulate the engine easily during build up. Assembly begins with bolting the high pressure turbine (that closest to the combustor) to the low-pressure turbine (that furthest from the cumbustor). Next, the combustion chamber is fastened to the turbines. One process that is used to build a balanced turbine assembly utilizes a CNC (Computer Numerically Controlled) robot capable of selecting, analyzing, and joining a turbine blade to its hub. This robot can determine the weight of a blade and place it appropriately for a balanced assembly.




11 Once the turbines and combustion chamber have been assembled, the high and low pressure compressors are attached. The fan and its frame comprise the forward most subassembly, and they are connected next. The main drive shaft connecting the low pressure turbine to the low pressure compressor and fan is then installed, thus completing the engine core.



12 After the final subassembly, the exhaust system, has been attached, the engine is ready to be shipped to the aircraft manufacturer, where the plumbing, wiring, accessories, and aerodynamic shell of the plane will be integrated.



Quality Control
As production begins on a newly designed engine, the first one built is designated a test engine, and numerous experiments are run to test its response to the various situations the engine model will encounter during its service life. These include extreme weather conditions, airborne debris (such as birds), lengthy flights, and repeated starts. The first engine built is always dedicated to quality testing; it will never fly commercially.

Throughout the entire process of building an engine, components and assemblies are inspected for dimensional accuracy, responsible workmanship, and material integrity. Dimensional inspections are undertaken in many different ways. One common method is CNC inspection. A coordinate measuring machine (CMM) will inspect key features of a part and compare them to the designed dimensions. Parts are also inspected for material flaws. One method is to apply a fluorescent liquid over the entire surface of a part. After the liquid has migrated into any cracks or marks, the excess is removed. Under an ultraviolet light any surface imperfections that could cause premature engine failure will illuminate.

All rotating assemblies must be precisely balanced to insure safe extended operation. Prior to final assembly, all rotating subassemblies are dynamically balanced. The balancing process is much like spin-balancing the tire on your car. The rotating subassemblies and the completed engine core are computer "spun" and adjusted to insure that they rotate concentrically.

Functional testing of a finished engine takes place in three stages: static tests, stationary operating tests, and flight tests. A static test checks the systems (such as electrical and cooling) without the engine running. Stationary operating tests are conducted with the engine mounted on a stand and running. Flight testing entails a comprehensive exam of all the systems, previously tested or not, in a variety of different conditions and environments. Each engine will continue to be monitored throughout its service life.






Types of Jet Engines


Turbojets
The basic idea of the turbojet engine is simple. Air taken in from an opening in the front of the engine is compressed to 3 to 12 times its original pressure in compressor. Fuel is added to the air and burned in a combustion chamber to raise the temperature of the fluid mixture to about 1,100°F to 1,300° F. The resulting hot air is passed through a turbine, which drives the compressor. If the turbine and compressor are efficient, the pressure at the turbine discharge will be nearly twice the atmospheric pressure, and this excess pressure is sent to the nozzle to produce a high-velocity stream of gas which produces a thrust. Substantial increases in thrust can be obtained by employing an afterburner. It is a second combustion chamber positioned after the turbine and before the nozzle. The afterburner increases the temperature of the gas ahead of the nozzle. The result of this increase in temperature is an increase of about 40 percent in thrust at takeoff and a much larger percentage at high speeds once the plane is in the air.

The turbojet engine is a reaction engine. In a reaction engine, expanding gases push hard against the front of the engine. The turbojet sucks in air and compresses or squeezes it. The gases flow through the turbine and make it spin. These gases bounce back and shoot out of the rear of the exhaust, pushing the plane forward.


Turboprops
A turboprop engine is a jet engine attached to a propeller. The turbine at the back is turned by the hot gases, and this turns a shaft that drives the propeller. Some small airliners and transport aircraft are powered by turboprops.

Like the turbojet, the turboprop engine consists of a compressor, combustion chamber, and turbine, the air and gas pressure is used to run the turbine, which then creates power to drive the compressor. Compared with a turbojet engine, the turboprop has better propulsion efficiency at flight speeds below about 500 miles per hour. Modern turboprop engines are equipped with propellers that have a smaller diameter but a larger number of blades for efficient operation at much higher flight speeds. To accommodate the higher flight speeds, the blades are scimitar-shaped with swept-back leading edges at the blade tips. Engines featuring such propellers are called propfans.


Turbofans
A turbofan engine has a large fan at the front, which sucks in air. Most of the air flows around the outside of the engine, making it quieter and giving more thrust at low speeds. Most of today's airliners are powered by turbofans. In a turbojet all the air entering the intake passes through the gas generator, which is composed of the compressor, combustion chamber, and turbine. In a turbofan engine only a portion of the incoming air goes into the combustion chamber. The remainder passes through a fan, or low-pressure compressor, and is ejected directly as a "cold" jet or mixed with the gas-generator exhaust to produce a "hot" jet. The objective of this sort of bypass system is to increase thrust without increasing fuel consumption. It achieves this by increasing the total air-mass flow and reducing the velocity within the same total energy supply.


Turboshafts
This is another form of gas-turbine engine that operates much like a turboprop system. It does not drive a propellor. Instead, it provides power for a helicopter rotor. The turboshaft engine is designed so that the speed of the helicopter rotor is independent of the rotating speed of the gas generator. This permits the rotor speed to be kept constant even when the speed of the generator is varied to modulate the amount of power produced.


Ramjets
The most simple jet engine has no moving parts. The speed of the jet "rams" or forces air into the engine. It is essentially a turbojet in which rotating machinery has been omitted. Its application is restricted by the fact that its compression ratio depends wholly on forward speed. The ramjet develops no static thrust and very little thrust in general below the speed of sound. As a consequence, a ramjet vehicle requires some form of assisted takeoff, such as another aircraft. It has been used primarily in guided-missile systems. Space vehicles use this type of jet.

Jet Engine: How Products are Made

http://www.defence.pk/forums/military-aviation/72354-thrust-weight-ratios-all-fighter-planes.html
http://www.defence.pk/forums/military-aviation/118218-engines-used-different-fighters.html
http://www.defence.pk/forums/military-aviation/94948-radar-ranges-different-fighters.html
http://www.defence.pk/forums/military-forum/20908-rcs-different-fighters.html

http://www.defence.pk/forums/china-...ures-j11b-navy-j11bs-j15-equip-th-engine.html
http://www.defence.pk/forums/military-aviation/23474-fighter-aircraft-cockpit-designs-7.html
http://www.defence.pk/forums/military-photos-multimedia/75408-combat-aircraft-designs-40.html

 

[Manticore]

Making jet fan blades that have a long usable lifetime has long proven very difficult or impossible for China and most other countries. They have been unable to make blades the metal of which did not "creep" and disable the engine. Solving this problem was advanced metallurgy and one of the crown jewels of the Western defense establishment. However, thanks to new turbofan engine technology from Britain’s Rolls Royce, the Xian Aircraft Corporation is now able to build its long-delayed JH-7A fighter bomber for the PLA Navy and Air Force, providing a new strike platform to use against U.S. naval forces or US allies and friends in the region. This fighter-bomber program had been dormant since the late 1970s for the lack of an effective engine. In the late 1970s China purchased a small number of Rolls Royce Spey Mk 202 turbofans, but a co-production deal faltered and Xian spent nearly 20 years trying to make a copy. Xian’s fighter-bomber was resumed in the early 1990s as a domestic counterpart to the planned purchase of Russian Sukhoi Su-30MKK strike fighters. But it did not become a viable program until the late 1990s when the Xian Aero Engine Group revived cooperation with Rolls Royce. This likely began in 1998, two years after London’s reinterpretation of the 1989 EU embargo. Xian purchased additional used Spey Mk 202s and purchased the necessary technology to begin production of an uprated Spey, called the QinLing.

The intended turbofan engine for the Su-35B is a major upgrade to the AL-31F that is designated 117S and whose profile can be found below in the Engines section of this article. This engine has full rotating, vector thrust nozzles which provide maximum maneuverability to the aircraft. Russian jet fighter design continues to give pilots exceptional maneuverability options in air combat situations. “The modernization has increased the engine special mode thrust by 16%, up to 14,500 kgf. In the maximum burner-free mode it reaches 8,800 kgf.”

An important Chinese priority is the conclusion of a 20 year project to redesign of the Russian Saturn AL-31FN. The WS10A turbofan engine designed by the Shenyang Liming Motor Company is slated to power the back bone of the Chinese air force. One model will power the J-10 fighter, another the J-11B. It has been in development for more than a decade and has had air trials with a Russian Su-27SK (Flanker B).

Another blog thread has discerned that the Chinese are taking a serious look at a derivative of the Saturn/Lyulka AL-31/41 family, and/or the Saturn 117S, to power J-20 prototypes. In 2005, production was initiated for the WS-9, a Chinese design based upon a Roll Royce turbofan engine. Most experts doubt the Chinese capacity to produce the requisite engine with a thrust in after burning mode of 13 to 14 tons. Indeed, the Chinese turbofan industry is on the public record as disappointed at their three decades of advanced engine development, with an admission that industry leadership still remains with the Russian Saturn/Lyulka and Rolls Royce in the UK.


Russia / MMPP Salut turbofan engine

 

[Manticore]

The Russian Saturn/Lyulka AL-31 turbofan engine has been a reliable, strong engine for many years. It functions very well in diverse environments and flight speeds, from deep surge to flat, straight and inverted spins. Exceptional maneuverability during extreme aerobatics with negative speeds up to 200 km/hr is ensured. Average price of the export AL-31 was $USD2.8 million in 2002.

In 2001 or 2002, Saturn/Lyulka began to modernize its Al-31F to the 31FM1-AL (AL-31F series 42, serial No Izdelije 99M1) at the Moscow Salyut plant and serial production began in March, 2007 and the engine was unveiled to the public at MAKS 2007. Stroke was increased from 12,500 to 13,500 kp and operating time to first major maintenance was extended from 750 to 1,000 hrs. A new low pressure compressor was integrated into the engine design. Control system was upgraded and a new supersonic nozzle has a lifetime of 800 hours. Overall engine weight increased slightly to 1557 kg.
Russia – Saturn AL-31-FM turbofan engine

Testing was conducted at the MM Gromova Institute using the Sukhoi 27 fighter during the summer of 2006. China was/is very interested in the AL-31FM1 model to modernize its fleet of Sukhoi-27 and Sukhoi-30 fighters.

Development continues as Salyut's goal is have a turbofan engine adquate to the demands of a Fifth Generation stealth fighter. The AL-31FM2 (Izdelije 99M2, or AL-31FSM (M1S)) and AL-31FM3 are late models. The AL-31FM2 has a low pressure compressor and adjustments in aerodynamics over earlier AL-31 models. Depression has been increased to 4.0 and the input can operate at 1467-1507 ºC. Stroke is now 14,200 kp or slight higher as of January 2007 information, kp is at least 1,000 hrs.

The AL-31FM3 will no longer specify at least 20% increase in stroke vrs the AL-31F, and 14,500 kp has been quoted for the AL-31FM3-1 and 15,200 kp for the AL-kp 31FM3. Pressure has been increased on the low pressure compressor and advanced heat resistant materials are used throughout the engine.

Note that "AL-31FN engine nozzles have three distinct parts. 1. A silver ring connecting the engine to the fuselage. 2. Blue-ish pedals that allow the nozzle to move. 3.The brownish exhaust nozzle pedals."

The first choice engine for the Chinese J-10 fighter was the Pratt & Whitney 1120 from the United States which had been designed for the Israeli Lavi fighter whose specifications influenced the design of the J-10. Subsequent diplomatic developments negated that option and the Chinese turned once again to Russia and their new Saturn AL-31FN turbofan engine of which nine were to be built and tested starting in 1992. Subsequently, 1500 successful test fights were made in China but the competition between Saturn and Salyut turned ugly, particularly over the legalities of intellectual property.

 

[Manticore]

In December 2005, journalists were allowed to see an AL-31FN engine with thrust increased to 13,500 kp. This development was financed internally by Salyut company. Contracts were signed for the manufacture of the AL-31FN in China, more precisely the assembly and refinement of kit engines as delivered. The rear of the J-10 has a small footprint in which the AL-31FN will fit nicely. The first shipment from Salyut was for 54 engines, the second in 2005-2006 delivered 100 engines. Price per engine is unclear, but may have increased to $USD 25 million in the second order. The Saturn AL-31FN turbofan is the engine of choice for the heavyweight version of the new, 'black project', J-13 stealth fighter.

RUSSIA / AL-31FP TURBOFAN ENGINE

The Russian AL-41F (Izdelije 20) is the first Russian Fifth Generation turbofan engine and at the time of its testing featured many aspects not seen elsewhere. The AL-41F had 'new' aerodynamic characteristics and used state of the art materials such as heat resistant ceramics, carbon composites, compounds that incorporated boron and aluminum into their molecular structure etc. This engine has been under development since 1995 at Liulka, the Moscow facility of Saturn. It is believed comparable to the engines that power the USA F-119, F-22 and the Euro 2000, Joint Strike Fighter.
Russia – Saturn 41F1A turbofan engine

 

[Manticore]

Some specifications are available for the AL-41F. Thrust to weight ration has been increased from the 8:1 characteristic of the AL-31F engines to 11:1. Weight reduction and increased strength follow upon a reduction in the number of high compressor stages, and an increase in total compression, features that were available in Russian 4th Generation Engines upon special request from the customer. Super cruise is an option – flying at supersonic speeds without using the afterburner. As a result, turbine gas temperature undergoes an unprecedented increase to 1600ºC. A state-of-the-art digital engine management system is integrated into the computer control system of the aircraft, the cost of this advance $USD 6-700 million. After ground tests, the AL-41F was evaluated on a Tubolev Tu-16 bomber.

The little known Chengdu two engine, J-13 stealth fighter may be powered by two AL-41 turbofan engines with thrust vectoring nozzles and supersonic cruise capability. Maximum takeoff will be ~20 tons, and the J-13 will be 'heavyweight' fighter.

Russia – MIG 1.42 / Lyuks-Saturn AL-41F engine

Russia – Saturn 117S (scaled down AL-41F), turbofan engine

The Article 117S (aka AL-41F-1A) is in essence a scaled down AL-41F, which outperformed Salyut's AL-31FM2 in bench tests. Thrust has been increased to 14,500 kgf in special thrust mode, and to 8800 kgf in maximum burner free mode. Between repair time has increased to 1,000 hours, operating period before first major maintenance is 1500 hours. The 117S was developed by PO Saturn Research and Production Association. They feature a new fan, new high and low pressure turbines, and a new digital control system. A vectored thrust nozzle is also an option.

The 117S engines will be manufactured by Ufa-based Motor Building Association and the Rybinsk-based NPO Saturn Research and Production Association. The first production 117S engines were delivered to KnAAPO in early 2007 in time for testing on the first Su-35 protoypes. The intended turbofan engine for the Su-35B is a major upgrade to the AL-31F that is designated 117S: see profile below in the Engines section of this article. This engine has full rotating, vector thrust nozzles which provide maximum maneuverability to the aircraft. Russian jet fighter design continues to give pilots exceptional maneuverability options in air combat situations. “The modernization has increased the engine special mode thrust by 16%, up to 14,500 kgf. In the maximum burner-free mode it reaches 8,800 kgf." In China, this engine is intended for the J-20, stealth fighter prototypes.

 

[Manticore]

According to , China's three main engine design and manufacture centers are: Liyang Aero-Engine Corporation (LYAC) in Guizhou, Liming Aero-Engine Manufacturing Corporation (LMAC) in Shenyang and Xi'an Aero-Engine Corporation (XAC) - has been obtained by . Although, great advances have been made, China still depends on Russia for two of its most advanced fighters. “The Chengdu J-10 fighter is powered by the Salyut AL-31FN: a derivative of the Sukhoi Su-27's Saturn/Lyulka AL-31F. The FC-1/JF-17 fighter is fitted with one Chernyshev RD-93 engine: a variant of the Mikoyan MiG-29's Klimov/Isotov RD-33." Both aircraft are on track for use by China's major defence export customer, Pakistan. JF-17s are already being assembled at the Pakistan Aeronautical Complex (PAC) and the J-10 planned for acquisition is being designated FC-20 in service.


In 1960, China was recovering from the Korean War and a terrible civil war. The aviation industry was taking a serious long range view as to objectives and programs to be initiated. With respect to jet engine development, the precision machining technologies and advanced materials required seemed to be a daunting challenge. Founded in 1961, the 606 Engine Design Institute cemented a partnership with the 601 Aircraft Design Institute in 1964 to design a fighter that was better than the J-7 (MiG-21 kit assembly) with an appropriately advanced turbine engine. The result was the J-9, high altitude, high speed interceptor equipped with the new WS-6 after burning turbofan engine. The WS-6 turbofan was ready for testing in June, 1968. In spite of delays caused by the Cultural Revolution, the engine was successfully tested for a total of 334 hours. In 1980, the 606 Institute designed an advanced WS-6G model which had higher low pressure, rotor speed, a three stage fan; and higher turbine inlet temperature. The cannular combustor of the WS-6 was now an annular combustor. The after burning thrust of the WS-6G was now 13.2%, and thrust to weight ratio was raised to 18.9%. The WS-6G began testing in February, 1982.

Turbofan development in China then stalled, there was no flight testing and the next phase of work went undone. By comparison, the WS-6 models appeared to be a second generation engine, 30 years behind what the turbofans made in the UK, Russia and the USA as thrust to weight ratio remained at 7. The subsequent development of the WS-9 seemed to say that the WS-6 and WS-6G were an impossible challenge and could not be used in the next advanced Chinese fighter, the Chengdu J-10.

 

[Manticore]

In late 1988, the prototype of the JH-7 fighter/bomber underwent flight tests. The USK Spey MK 202 turbofan engine was the engine of choice for the JH-7 but a partial embargo on the import of British turbofan engines was in force as of 1989. The WS-9, code named 'Qingling', was a stripped down version of the USK Spey MK 202 turbofan engine with modifications made to the blowers, compressor and a convergent-divergent nozzle. The development project was finished in 2002, a final design was approved in 2005 and in 2008 AVIC I Xian began mass production. Rumors indicate that an Improved WS-9 "Qingling" (T/W=10 17t class turbofan (WS-15/"large thrust") is being developed for the Fifth Generation J-20 stealth fighter.\

The Chinese version of the Spey Mk. 202 is the WS-9 which AVIC I and Xi'an Aero-engines decided to mass produce, most likely because it is the engine of choice for the Xian JH-7A attack bomber.

China – Rolls-Royce RB168-Spey Mk202 / cf CEGC WS-9 turbofan

China–WS-9 Qinling turbofan

 

[Manticore]

The history of the WS-10 turbofan serves to illustrate the trial and tribulations that have attended advanced aircraft engine development in China. The origin of the WS-10 begins in 1982 when the WS-6 program was canceled. The WS-10 team began with the 20 years of experience gained from the WS-6 project. The WS-10 program closely studied the USA/France CFM56 engine and the General Electric F101-GE-102 engine that powered the American long range, strategic B-1B bomber. In 1989, three areas in indigenous turbofan design that needed serious improvement were identified: a) the high compressor; b) combustion chamber; and c) short cooling, turbine blades. A core engine technology demonstrator - Medial Turbofan Thrust Demonstration Core Engine (MTDTCE) - was completed and launched for testing in December, 1992. Experts on the Russian AL-31F were consulted and were instrumental in moving the project forward. The design and development work was so complex and 'new' that 21 teams participated in the project.

The research and development of advanced turbofan engines has been the purview of the 606 Institute ( Shenyang Aero-Engine Research Institute) and the 624 Institute ( China Gas Turbine Establishment). A wide range of turbofans were envisaged that would power not only combat aircraft but training aircraft, UAV and cruise missiles. In 1980, the High-Performance Propulsion System Preliminary Development (HPPSPD) program was commissioned.

Work began in 1987 to design two engines for combat aircraft: the WS-10A Taihang and WS-13 Taishan. The WS-10A would produce 13,500 kg of thrust with after burning, and 7.5:1 thrust ratio. On June 12, 1989 the Liming Aircraft Engine Company received an order for the first three components that were the result of the HPPSPD project. In July of the same year, a closed door conference was held on “Three Most Important Parts of High Pressure Compressor: 7 stage high pressure compressor, short annular combustor with air blast atomizer and an air film cooling blade. These three components were believed essential to producing a Chinese made turbofan engine and achieving independence from Russia and Britain.

To be designed by the 624 Institute, the core engine was modeled as a medial thrust and small bypass ratio turbofan with thrust to weight ratio of 8:1. It was called the Medial Thrust Demonstration Turbofan Core Engine (MTDTCE), and was on the list of 18 significant high-tech projects financed by China's Commission of Science Technology and Industry for National Defence (COSTIND) Eighth-Five-Year Plan. As of January 1991, three milestones in the MTDTCE Program had been reached: design completion, fabrication of one demonstration engine, and production of high pressure compressor components. Design and castings for main forging were completed in February, 1992. In June 1992, a full scale metallic model of the turbofan engine was unveiled.

Manufacture of the MTDTCE was done at the 403 plant and involved 21 industrial and research and development facilities. Prototype production began in March 1992 for sub-assemblies such as the directionally solidified blade forgings, short annular combustor, precision forgings of diffuser with shaped blade and electron beam welding of compressor sections. The first finished sub-assemblies of MTDTCE were presented on November,18, 1992. The turbofan hot sections were integrated with the exhaust nozzle and gearbox and the MTDTCE was fixed on a ground testing rig on November 24, 1992. On December 3, 1992, the MTDTCE was powered up for the first time and during its 11th test on December 12, it reached maximum speed.

China, Shenyang-WS-10A Engine / Zhuhai Air Show 2008

China – Shenyang WS-10 turbofan engine

 

[Manticore]

The flight test aircraft was a Chinese J-11 – a Russian Sukhoi Su-27 'kit' assembled in China. Unfortunately, the oil tank and exit nozzle dimensions were not a match to the J-11, and between 1992 and 1997 the program did not move forward. An engine explosion in 1997, further delayed progress. In 1998, the J-10 which flew used a modified AL-31FN engine. In 2004, a bearing failure in the engine caused an aircraft to land (safely) on one engine. Nonetheless, after more than 20 years of development, the WS-10 pass 40 days of final tests for battery life and operational durability and was 'signed off' as ready for the PLAAF on November 10, 2005.

China – Shenyang J-11B w/ WS-10 turbofan engine

Thrust ranges from 13,200 to 13,500 kp (> 130KN) and first installation is assumed to be on the J-11B. The J-10 requires modifications to dimensions and increased stroke, this model to be labeled WS-10B. The WS-10A has a 7 ? compressor, a short combustion chamber and mono turbine blades made from nickel alloy. It is a high pressure turbine in a single stage design, low pressure in the two stage design. Reportedly, the WS-10A has been tested with a steerable nozzle thrust vector 15º in any direction. Not yet confirmed in the western aviation press was the expected delivery in 2007 of 15 to 20 WS-10A turbofan engines to be installed on 7 or 8 twin engine J-11B aircraft. On February 2008, AVIC announced that the WS-10A ('Turbofan 'Taihang') has begun production and would be the engine installed on the J-10 series of fighters, the J-11B and the forthcoming J-14, Fifth Generation Stealth Fighter.

Work has begun on the WS-10B which increases the thrust from “13,469 kg (132 kN) to 13,766 kg (135 kN) and it is "this variant that is planned to replace the AL-31FN in later production batches of the J-10. A later version of this engine, the WS-10G, has a thrust increase to 15,800 kg (155 kN) and will become not only the standard engine for the J-10 and J-11 but also the power plant for the proposed J-13 combat aircraft."

WS-12 Taishan -

Terminated in 1999 due to lack of funding, the WS-12 engine program has been revived. The new Xi'an JH-7B attack bomber may well be powered by the LYAC WS-12B growth variant of the original WS-12 Taishan. "This engine gives the aircraft a thrust increase to 10,200 kg (100 kN) over the JH-7A strike aircraft's Xi'an WS-9 at 9,400 kg (92 kN).“

CHINA - WS-13 "TAISHAN" / TURBOFAN ENGINE



Work had now begun on the WS-13 Taishan turbofan which is rated at 86.37kN with after burning. However priority soon shifted over to the WS-14 for the Shenyang J-8IIIf fighter, WS-13A for the J-7MG fighter, and the Rolls Royce Spey Mk202 for the Xian JH-7A attack bomber. The WP-13A turbofan is intended for the J-7MG; the WS-13 will power both the Chengdu JF-17 Thunder and the FC-1 Fierce Dragon fourth-generation multi-role combat aircraft.

China – WS-13B Taishan engine

 

[Manticore]

The WP-14 Kunlun is a 78kN turbofan with thrust to weight ratio of 7:1 designated for the Shenyang J-8III fighter that was cleared for production in May, 2002. At the 2006 Zhuhai Air Show, a new 95KN engine was reported as under development and designated WS-14. The 'mysterious' mockup engine seen at the 2008 Zhuhai Air show may be this WS-14 model, a high thrust variant of the WS-10 designated WS-10D. The inlet fan engine appears to be influenced by RD-22/93 and maximum thrust to 155KN can be predicted.

"The new, modernised version of the Shenyang J-8 fighter, designated the J-8T, which will also receive a new engine. The 8,160 kg (80 kN) LYAC WS-12 Taishan engine will be replaced by a LMAC WP-14C Kunlun-3 with 8,360 kg (82 kN) thrust. The same engine will also be installed in the Chengdu J-7 fighter and Guizhou (GAIC)/Chengdu JL-9/FTC-2000 jet trainer.”

China – CEGC WS-18 turbofan

China - 9500kgf turbofan engine

 

[Manticore]

The RD-33 turbofan engine was developed in OKB-117 lead by S. P. Izotov (now OAO Klimov) from 1968, production started in 1981. It is an 8,000 to 9,000 kilograms-force (78,000 to 88,000 N; 18,000 to 20,000 lbf) thrust class turbofan twin-shaft engine with afterburner built by the Klimov company of Russia and has several variants. It features a modular design, individual parts can be replaced separately and has a good tolerance to the environment. The RD-33 is simple to maintain and retains good performance in challenging environments

rd93
A variant used to power the JF-17 / FC-1. According to JF-17.com "The most significant difference being the repositioning of the gearbox along the bottom of the engine casing." The Klimov poster
http://dc368.*******.com/img/mi3wj5Kk/rd93.JPG

 

[Firemaster]

nice thread by antibody very informative

 

[Manticore]

chinese members can add the different comparison pics of engines being tested on the j11bs , j14 , j20

posts on american , british and french engines would be next , however i think they would be a longer list..

 

[fatman17]

nice-job antibody

 

[Manticore]

thankyou sir!