Kuznetsov NK-93
   HOME

TheInfoList



OR:

The Kuznetsov NK-93 was a civilian
aircraft engine An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Aircraft using power components are referred to as powered flight. Most aircraft engines are either piston engines or gas turbin ...
, a hybrid between a
turbofan A turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft engine, aircraft propulsion. The word "turbofan" is a combination of references to the preceding generation engine technology of the turbojet and the add ...
and a
turboprop A turboprop is a Gas turbine, gas turbine engine that drives an aircraft Propeller (aeronautics), propeller. A turboprop consists of an intake, reduction drive, reduction gearbox, gas compressor, compressor, combustor, turbine, and a propellin ...
known as a
propfan A propfan, also called an open rotor engine, open fan engine is an aircraft engine combining features of turbofans and turboprops. It uses advanced, curved propeller blades without a ducted fan, duct. Propfans aim to combine the speed capabili ...
. The engine was also unique in having a separate duct around the
contra-rotating propellers Aircraft equipped with contra-rotating propellers (CRP) coaxial contra-rotating propellers, or high-speed propellers, apply the maximum power of usually a single engine piston powered or turboprop engine to drive a pair of coaxial propellers i ...
, as most other propfans are unducted. Once described in a respected aviation encyclopedia as "potentially the most fuel-efficient aircraft jet engine ever to be tested", the NK-93 was targeted for derivatives of Soviet/Russian airliners such as the
Ilyushin Il-96 The Ilyushin Il-96 () is a Russian Four-engined jet aircraft, four-engined jet long-haul Wide-body aircraft, wide-body airliner designed by Ilyushin in the former Soviet Union and manufactured by the Voronezh Aircraft Production Association in R ...
,
Tupolev Tu-204 The Tupolev Tu-204 () is a twin-engined medium- range narrow-body jet airliner capable of carrying 210 passengers, designed by Tupolev and produced by Aviastar-SP and Kazan Aircraft Production Association. First introduced in 1995, it was in ...
, and
Tupolev Tu-330 The Tupolev Tu-330 was a proposed Russian medium-size transport aircraft developed by Tupolev since the early 1990s. The project was stopped around 2000s due to lack of funding and difficult economic situation of the Russian aircraft industry at ...
. Five in-flight engine tests were conducted on the NK-93 from December 2006 to December 2008.


Development

The NK-93 engine was developed beginning in the late 1980s, although the design of the engine was allegedly envisioned as early as 1968. Many of the design features were adopted from the Kuznetsov NK-92, the military complement to the NK-93. The core of the NK-93 was to form the foundation of a family of direct-drive turbofans and geared propfans, ranging from in
thrust Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that ...
. It was the last major project of
Kuznetsov Design Bureau The Kuznetsov Design Bureau (, also known as OKB-276) was a Russian design bureau for aircraft engines, administrated in Soviet times by Nikolai Dmitriyevich Kuznetsov. It was also known as (G)NPO Trud (or NPO Kuznetsov) and Kuybyshev Engine D ...
founder Nikolai Dmitriyevich Kuznetsov. The NK-93 was originally scheduled for flight testing in late 1993/early 1994 and certification in 1997 so that it could be used on the
Ilyushin Il-96 The Ilyushin Il-96 () is a Russian Four-engined jet aircraft, four-engined jet long-haul Wide-body aircraft, wide-body airliner designed by Ilyushin in the former Soviet Union and manufactured by the Voronezh Aircraft Production Association in R ...
M and
Tupolev Tu-204 The Tupolev Tu-204 () is a twin-engined medium- range narrow-body jet airliner capable of carrying 210 passengers, designed by Tupolev and produced by Aviastar-SP and Kazan Aircraft Production Association. First introduced in 1995, it was in ...
M. By May 1994, seven full-size versions of the engine had been built, with five of them close to the production configuration. Due to the
breakup of the Soviet Union The Soviet Union was formally dissolved as a sovereign state and subject of international law on 26 December 1991 by Declaration No. 142-N of the Soviet of the Republics of the Supreme Soviet of the Soviet Union. Declaration No. 142-Н of ...
, though, the schedule was repeatedly delayed because of severe funding shortages and other issues. However, by October 2001, a tenth NK-93 engine neared completion, out of a total of 15 planned engine prototypes. The engine finally underwent flight testing on an
Ilyushin Il-76 The Ilyushin Il-76 (; NATO reporting name: Candid) is a multi-purpose, fixed-wing, four-engine turbofan strategic airlifter designed by the Soviet Union's Ilyushin design bureau as a commercial freighter in 1967, to replace the Antonov An-1 ...
LL
testbed aircraft A testbed aircraft is an aeroplane, helicopter or other kind of aircraft intended for flight research or testing the aircraft concepts or on-board equipment. These could be specially designed or modified from serial production aircraft. Use of ...
beginning on December 29, 2006, with a second flight occurring on May 3, 2007. A total of 50 flight test hours were planned. Testing was suspended again in June 2007 because of funding troubles. Airborne testing did not restart until October 2008, with flights on October 2 and 6. Another test flight occurred on December 15, 2008, but the NK-93 was removed from the testbed by May 14, 2009. Supporters of the NK-93 claim that the amount of money needed to certify the engine is minuscule compared to the development costs of competing new Russian engines, which they regard as still inferior to the older NK-93. In April 2014, Kuznetsov announced that it would resume work on the NK-93 engine.


Foreign interest

The advanced nature of the engine attracted the attention of airframers and engine manufacturers in other countries. By 1992, the NK-93 was already drawing interest from the Japanese aviation industry. Investors from South Korea were among the groups discussing investment in the NK-93 at the 2001
MAKS air show MAKS (, ) is an international air show held at Zhukovsky International Airport, the home of the Gromov Flight Research Institute in Zhukovsky, Moscow Oblast, Zhukovsky, southeast of Moscow, Russia. The event was organized by the Russian Ministr ...
. In 2004,
Airbus Airbus SE ( ; ; ; ) is a Pan-European aerospace corporation. The company's primary business is the design and manufacturing of commercial aircraft but it also has separate Airbus Defence and Space, defence and space and Airbus Helicopters, he ...
and the Kuznetsov Design Bureau studied the feasibility of using the engine to power Airbus commercial aircraft. German engine maker
MTU Aero Engines MTU Aero Engines AG is a German aircraft engine manufacturer. MTU develops, manufactures and provides service support for military and civil aircraft engines. MTU Aero Engines was formerly known as MTU München. History While the Munich-based e ...
purchased a Kuznetsov report on the noise characteristics of the NK-93 engine for 600,000
Deutsche mark The Deutsche Mark (; "German mark (currency), mark"), abbreviated "DM" or "D-Mark" (), was the official currency of West Germany from 1948 until 1990 and later of unified Germany from 1990 until the adoption of the euro in 2002. In English, it ...
s. When the NK-93 was displayed on the Il-76LL demonstrator at the 2007 MAKS air show, Chinese aircraft manufacturers reportedly made a "tempting offer" to buy all of the NK-93's blueprints and documentation. In October 2013, the European Commission gave a three-and-a-half-year grant to study the ''Innovative Counter rOtating fan system for high Bypass Ratio Aircraft engine'' (COBRA). COBRA was a European Union-Russia cooperative program to study an ultra-high
bypass ratio The bypass ratio (BPR) of a turbofan engine is the ratio between the mass flow rate of the bypass stream to the mass flow rate entering the core. A 10:1 bypass ratio, for example, means that 10 kg of air passes through the bypass duct for eve ...
(UHBR) counter-rotating turbofan (CRTF) that was similar to the NK-93. Participating organizations included Kuznetsov, CIAM, Russian propeller manufacturer Aerosila, French engine maker
Safran Safran S.A. () is a French Multinational corporation, multinational aerospace, defence industry, defence and computer security, security corporation headquartered in Paris. It designs, develops and manufactures both commercial and military airc ...
(Snecma), the French aerospace laboratory (
ONERA The Office National d'Études et de Recherches Aérospatiales ( English: National office for aerospace studies and research) or ONERA, dubbed ''The French Aerospace Lab'' in English, is the French national aerospace research center. Originally f ...
), and the
German Aerospace Center The German Aerospace Center (, abbreviated DLR, literally ''German Center for Air- and Space-flight'') is the national center for aerospace, energy and transportation research of Germany, founded in 1969. It is headquartered in Cologne with 3 ...
(DLR).


Design

The NK-93 has a core that was developed from the NK-110, an unducted Kuznetsov propfan that was never built. Its Aerosila SV-92
contra-rotating propeller Aircraft equipped with contra-rotating propellers (CRP) coaxial contra-rotating propellers, or high-speed propellers, apply the maximum power of usually a single engine piston powered or turboprop engine to drive a pair of coaxial propellers i ...
s are in diameter, have eight blades on the front propeller and ten blades on the back propeller. The engine has a rated thrust of , a maximum thrust of , a cruise SFC of 0.49 kg/(kgf⋅ h), and a
takeoff Takeoff is the phase of flight in which an aerospace vehicle leaves the ground and becomes airborne. For aircraft traveling vertically, this is known as liftoff. For aircraft that take off horizontally, this usually involves starting with a tr ...
SFC of 0.234 kg/(kgf⋅h). 13% of the thrust is produced directly by the gas generator, while the rest of the thrust is produced through the turning of the ducted fans. The front and back fans are both variable-pitch propellers; by 1993, the coaxial fans could combine to produce 85% of the desired maximum
reverse thrust Reverse or reversing may refer to: Arts and media *Reverse (Eldritch album), ''Reverse'' (Eldritch album), 2001 *Reverse (2009 film), ''Reverse'' (2009 film), a Polish comedy-drama film *Reverse (2019 film), ''Reverse'' (2019 film), an Iranian cr ...
, and by 1995, the reverse thrust capability was . The engine has a bypass ratio of 17 and is designed around a
planetary gearbox An epicyclic gear train (also known as a planetary gearset) is a gear reduction assembly consisting of two gears mounted so that the center of one gear (the "planet") revolves around the center of the other (the "sun"). A carrier connects the ...
with seven satellites.


Applications

* Antonov An-70 (proposed twin-engine version) *
Antonov An-124 The Antonov An-124 Ruslan (; ; NATO reporting name: Condor) is a large, strategic airlift, four-engined aircraft that was designed in the 1980s by the Antonov design bureau in the Ukrainian SSR of the Soviet Union (USSR). The An-124 is the ...
(proposed re-engine) *
Ilyushin Il-76 The Ilyushin Il-76 (; NATO reporting name: Candid) is a multi-purpose, fixed-wing, four-engine turbofan strategic airlifter designed by the Soviet Union's Ilyushin design bureau as a commercial freighter in 1967, to replace the Antonov An-1 ...
LL (testbed) *
Ilyushin Il-96 The Ilyushin Il-96 () is a Russian Four-engined jet aircraft, four-engined jet long-haul Wide-body aircraft, wide-body airliner designed by Ilyushin in the former Soviet Union and manufactured by the Voronezh Aircraft Production Association in R ...
* Sukhoi KR-860 *
Tupolev Tu-154 The Tupolev Tu-154 (; NATO reporting name: "Careless") is a three-engined, medium-range, narrow-body airliner designed in the mid-1960s and manufactured by Tupolev. A workhorse of Soviet and (subsequently) Russian airlines for several decades, ...
M3 *
Tupolev Tu-204 The Tupolev Tu-204 () is a twin-engined medium- range narrow-body jet airliner capable of carrying 210 passengers, designed by Tupolev and produced by Aviastar-SP and Kazan Aircraft Production Association. First introduced in 1995, it was in ...
*
Tupolev Tu-330 The Tupolev Tu-330 was a proposed Russian medium-size transport aircraft developed by Tupolev since the early 1990s. The project was stopped around 2000s due to lack of funding and difficult economic situation of the Russian aircraft industry at ...


Specifications


See also


References


Bibliography

* * * * ** * * * * * * * * {{Kuznetsov aeroengines Kuznetsov aircraft engines Propfan engines