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Su-47 Berkut

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

Su-47 "Berkut" (C-37) - a project Russia perspective based fighter, developed by OKB. dry. Fighter aircraft has swept wing, in airframe widely used composite materials. Chief designer - Mikhail Pogosyan.

Su-47 Berkut – video

In the late nineties and early two thousandth's "highlight of the program" Russian airshows became the new C-37 "Berkut", later received a new index of the Su-47. The unusual appearance of the aircraft, associated with forward swept wing (CBS), He drew the attention of all the people, aviation-related, or simply interested in her. Excitement around the project C-37, often referred to as the main reliable domestic military aviation, in no way inferior to the later debate and discussion of the current program PAK FA. Professionals and aviation enthusiasts predicted the company's development of the "Dry" has a great future and trying to anticipate, how effective it will be in the army. However, since the first Su-47 flight passed over 15 years, and the Air Forces of Russia have not received serial fighters, based on this project. Only after several years of heated discussions in the public mind to the understanding of the fact, that C-37 was purely experimental and from the very beginning was not considered as a basis for drill technology of the near future. Nevertheless, a number of "Berkut" project nuances remains a secret until now, which sometimes leads to renewed controversy.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

secrecy

The first prototype of the aircraft C-37 took to the air 25 September 1997 of the year. However, the existence of a secret project, it became known earlier. Also in 1994-95 Aviation's foreign press wrote about the development of some promising Russian fighter. Western journalists cited the alleged name of development - C-32. Besides, in some publications speculated about the interesting technical features of the project. According to provide information, the new C-32 was to have a forward-swept wing.

As it turned out, foreign aviation journalists were partially right. Confirm their assumptions appeared in early 1996 of the year. Then the publication "Journal of Air Force" has published photos from the meeting Air Force Military Council. On it except for the aviation industry and the Air Force were present two small model airplanes. In one of them quickly identified already known fighter Su-27M, and the second caused a lot of questions. Layout black with white numerals "32" on board had canards and - most importantly - the characteristic swept wing. A few months after the publication in the foreign press were diagrams and drawings, made on the basis of available photos.
In this case, it is impossible not to note the official reaction of the company "Sukhoi". All questions about the fighter project with CBS representatives answered the same design bureau: no work in this direction is not conducted. As it turned out, such answers, more like excuses, It was due to privacy mode. As for the secret papers, they started back in the early eighties.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

At WAYS for "Berkut"

In the late seventies and early eighties, the Air Force leadership, together with the State Committee for Aviation Technology at the USSR Council of Ministers (GKAT) We reflected on the state of the fleet in the next decade. AT 1981 year program launched I-90, the purpose of which was to define and shape the development of "Fighter of the nineties". The parent company in the project I-90 was their design office. Mikoyan. Sukhoi has managed to convince the leadership in the industry, that the existing Su-27 has a large modernization perspective and so the organization can engage in other projects.
New Chief Designer Design Bureau. Dry Stamp. Simonov, appointed in the early eighties, I offered yet to start a new fighter project, but keep it on its own initiative. Last nuance project, probably, It was driven by the desire to do the designers perspective, but controversial subjects, which could not provide any actionable results. Airplane with the symbol C-22 proposed to apply a forward-swept wing. Compared with traditional designs, it had a number of substantial advantages:

– greater aerodynamic efficiency at maneuvering. This is especially true at low speeds;
– large lifting force compared to the wing straight sweep of the same area;
– the best conditions of work mechanization, leading to improved takeoff and landing performance and manageability;
– lower the stall speed in comparison with a straight wing sweep and the best characteristics antispin;
– wing displacement force elements closer to the fuselage tail, that frees up volumes for gruzootseke near the aircraft's center of gravity.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

These and other advantages of CBS to create a new fighter, the characteristics of which would be significantly higher, than the machines of the traditional scheme. But, as always, benefits were accompanied by serious shortcomings and problems, to be solved in the near future. swept wing has set the following questions designers:
– elastic divergence wing. CBS at certain speeds begins to curl, which can lead to its destruction. solution to the problem seen an increase in the stiffness of the wing;
– dead weight. Enough rigid wing, made of the currently available materials, It was a bit too heavy;
– drag. With further increase in speed quite rigid wing sweep negative faces new challenges. The specific nature of the wing flow leads to a noticeable increase in drag as compared with the characteristics of the wing with a straight sweepback;
– the offset of the aerodynamic center. At high speed aircraft with CBS forced to actively carry out longitudinal balance.
Only solution to all these problems,, directly related to the forward swept wing, It could have a positive effect in the form of benefits described above. Designers led by MP. Simon looked for solutions.
Already in the early stages of the project C-22 identified the main technological solutions, that were later used in C-37. Wing sufficient rigidity offered to do with the extensive use of carbon fiber reinforced plastics. Number of metal parts reduced to a minimum. Besides, Wing equipped with advanced mechanization deflected socks, designed to optimize the flow around at high angles of attack. the plane shape of the P-22 was determined by the mid-eighties. It was a single-engine fighter with aerodynamic configuration "duck". maybe, to the end of the decade could make its maiden flight the C-22, but in the Soviet Union there was no suitable engine. All available aircraft engines were not given the required thrust-weight ratio.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

Studies have been conducted to assess whether changes in the project under the new engine from the existing. These works have ended without success: aircraft still remained too heavy for the available engines. In this regard, based on the C-22 began designing the new C-32. Aerodynamic features of the C-32 is almost fully in line with the previous project, but the new power plant has been applied. Two turbofans RD-79m with a thrust of 18500 kg can provide sufficient performance potyazhelevshy car thrust-weight ratio. Furthermore, calculations showed, These engines were able to provide C-32 long flight at supersonic speeds without afterburner.
AT 1988 year, in view of the worsening economic situation in the country, Project C-32 was nearly closed, but for it intervened command of the Navy. Admirals familiar with the design characteristics of future aircraft and asked to create on its basis of carrier-based fighter. Within a few months they KB. Sukhoi Su-created the 27km project. In fact, it has been significantly modified glider C-32, equipped with the equipment and armament of the Su-33. according to the draft, the car had a maximum takeoff weight at 40 tonnes, that when using the RD-79m is not allowed to take off from aircraft carriers so springboard, as did the Su-33. To solve this problem it was proposed by TN. ballistic take-off. The essence of this method was that, that the lack of speed in the separation of the springboard compensated height characteristics and forward swept wing. thanks to CBS, losing a few meters of height, aircraft could gain the necessary speed and jump in level flight. Aircraft wing with sweepback could not use ballistic take-off, since insufficient lifting force and a horizontal rate guaranteed to be led to a fall in water.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

C-37 Project

The deteriorating economic situation in the country did not allow the Navy to get a promising carrier-based fighter. The Bureau plans to them. Dry included the construction of several prototypes of the Su-27km, but funding termination is not allowed to do so. In the early nineties, aircraft manufacturers have decided to continue the research on swept wing, using the already existing strengths. Another project was designed to combine all the achievements and technical solutions adjusted to the financial problems and the state of the aviation industry. The project was named C-37.

First of all it should be noted, that the reduction in funding and the return of the project status proactive impact on the number of planned prototypes. It was decided to build only one prototype. According to some sources, Glider built first sent to the static test, Where, using the most modern techniques, estimated its actual strength. Any load at the same time destroying not supplied, and all effects consistent with the calculated performance. This significantly reduced the cost of the project through the construction of additional airframes. After the first static test glider was equipped additionally to the state of full plane.

Ready experimental aircraft S-37 "Berkut" is interesting both for specialists, and to the general public. first attracted the attention of applied technology, the second - an unusual look and the alleged possibility. From the aerodynamic point of view C-37 is an integral longitudinal triplane with high wing forward swept. The front and tail horizontal tail formed all-moving, and are relatively small area. According to some reports, aerodynamic characteristics of the C-37 allow it to enter the angles of attack up to 120 ° and perform TN. dynamic braking ("Cobra Pugachev"), However, tests in the course of demonstrations of this feature is hardly used due to restrictions on flight mode.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

One of the main achievements of the Design Bureau. dry, Irkutsk Aviation Plant and related facilities can be considered the creation of the production technology of long composite parts. large flat parts are formed during the production, which then can be given a complicated configuration. Finished parts are joined to each other with high precision. The outer surface of the airframe C-37 consists of a large number of such composite panels, the largest of which has a length of about 8 m. Due to this the number of joints is minimized and different protruding parts, including fasteners. Ultimately, the use of large composite panels beneficial effect both on rigidity of the wing structure, and the aerodynamics of the entire aircraft.

Empty weight equal to P-37 19500 kg, with about 13% I fell on parts made of composite materials. In view of the experimental nature of the project in the construction of aircraft used not only specifically designed for new technology elements, but already mastered the production and borrowed from other aircraft. For example, chassis, lantern and some on-board systems with almost no changes were taken from the Su-27 aircraft.

swept aircraft wing C-37 has a console with a sweep at the leading edge of -20 ° and -37 ° at the rear. The root portion of the leading edge forming an influx of sweepback. Conjugation influx console and the forward and reverse sweep possible to improve the flow around in this part of the airframe. The front edge of the wing is equipped deflectable toe, back - Simplex flaps and ailerons. Mechanization is almost completely covers the edge of the wing. In view of the requirements for the stiffness of the wing structure on 90% It composed of composite parts. The remaining elements are made of metal and used in a power set.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

Close to the central portion of the fuselage, on either side of the air intake, the Su-37 has all-moving canards trapezoidal. Horizontal tail empennage tselnopovorotnym also satisfied and has the characteristic elongated shape with a large swept leading edge. Vertical tail similar to the keels of the Su-27, but has a smaller area. Due to some of the nuances of the design could significantly increase the efficiency of its work, which reduced the area.
Aircraft Fuselage C-37 has smooth contours, and its cross section is mainly close to the oval. The design of the bow of the structure close to the respective airframe Su-27. On the sides of the rear of the cockpit has unregulated air intakes. Their shape is formed by a circle sector, Truncated fuselage side surfaces and top center wing root influx. On the upper surface of the middle part of the fuselage, near the root of the wing, there are additional air intakes, used during takeoff and landing, or maneuvering under vigorous. As can be seen from the shape of the fuselage, the intake passage on the way to the engine curve, what, among other things,, It covers compressor blades and thereby reduces visibility of the aircraft in frontal projection. On either side of the nozzle engines on aircraft C-37 are relatively small fairings, inside which it can be taken by the necessary electronic equipment appropriate size.

In the absence of other suitable motor, ready for production, for mounting on C-37 were chosen turbofan D-30F11. These engines are a further development of the D-30F6, used on the MiG-31. anticipated, that in the future S-37 will be able to get a new, more advanced engines with greater thrust, lower fuel consumption and thrust vector control system. Turbojet engines with afterburning thrust of 15600 kg given plane with normal takeoff weight of about 25,6 ton fairly high performance. Declared maximum speed of flight - 2200 km / h at high altitude and 1400 km / h at sea level. Service ceiling was set at 18000 m, Practical range - 3300 kilometers.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

On the composition of aircraft equipment C-37 is still not known to a lot of. According to reports, the aircraft is equipped with a wire system, created on the basis EDSU Su-27. There are also inertial navigation system with the ability to use satellite navigation signal, as well as modern communication systems. In the C-plane 37 to facilitate the operation it was found pilot ejection seat K-36DM, characterized by serial production of this model. Backrest in "Golden Eagle" is angled 30 ° to horizontal. This helps the pilot to easily transfer overload, arising under intense maneuvering. According to some sources, C-37 used unusual for domestic combat aircraft controls: small pen was used instead of the standard central plane control knob, placed on the right of the dashboard. engine control handle and pedal at the same time remain the same, similar to those used on the Su-27.

Being experimental aircraft, prototype C-37 did not carry any weapons. Nevertheless, left the wing influx was the place for the automatic cannon GS-301 with ammunition (according to some, prototype still got a gun), and in the middle part of the fuselage had gruzootseke for weapons. As far as we know, during the first test C-37 did not carry any weapons, since the purpose of the mission was to test the flight characteristics of the machine.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

Tests and popularity

First flight 37-C (the first prototype based on the possible construction of a number of machines was called C-37-1) took 25 September 1997 of the year. Under the direction of a test pilot and. Votintseva new aircraft spent in the air for about an hour and did not cause any serious complaints. The first series of test flights lasted until spring 1998 of the year, after which he was made a break. For some time, the company "Sukhoi" designers analyzed the collected information, We make the necessary adjustments to the project, We modified the car and made up the program of the next stage of testing.

the general public for the first time C-37 "Golden Eagle" was shown only 1999 year at the international aerospace show MAKS. The demonstration could take place before, at the MAKS-1997. In the summer of 97-year experimental machine I was already in Zhukovsky and ready for testing. There have been proposals show experimental aircraft on static display, but the Air Force did not approve of their commanders. It is worth noting, after two years of "Berkut" also did not hit on the static. The level of secrecy of the project was that, that the only aircraft taxied on the runway airfield just before its demonstration flight. After planting, it was towed in one of the hangars, away from the spectators' eyes.

Despite the almost two-year delay in the public demonstration of the aircraft, the first information about it appeared in the media a few days after the first flight. Official confirmation of the existence of the new Russian plane with CBS produced the expected result - worldwide controversy erupted on the characteristics and prospects of the C-37. An interesting feature of the project media coverage was the fact, that "Berkut" almost immediately was declared a promising fifth-generation fighter, which for the very near future will go in the series and will be supplied to the troops. The statements of the company "Sukhoi" about the experimental nature of the project barely made their way through other information noise.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

Against the background of the mass discussion and heated debate employees of the company "Sukhoi", LII and related companies were testing a new aircraft, he collected a mass of important data. C-37-1 prototype helped to establish the validity of some technical solutions and show the fallacy of the other. At the beginning of the two thousandth's newly resumed talks on the establishment on the basis of C-37 combat aircraft. It was proposed to equip it with modern complex avionics, including forward-looking radar with a phased antenna array and an additional radar to monitor the rear hemisphere. The composition of promising fighter armament offered include guided and unguided missiles and bombs, that he could carry on the internal and external suspension.

Naturally, all attempts to create a combat aircraft based on the pilot of "Berkut" did not lead to any result. The company "Dry" has continued to use a single prototype purely for research purposes, from time to time showing his exhibitions. So, for example, at the MAKS-2001 C-37-1 was first seen under the new name - the Su-47. The reasons for this change were motivated, Firstly, drawing attention to the draft. Letter "C" in the practice of the company "Sukhoi" is always assigned to the prototype, and finished aircraft received index "Su". The name change had no effect on the test program.

Test aircraft C-37-1 or Su-47 continued for several years. The aircraft was tested at various speeds and flight modes. According to some reports, active check "Berkut" may have led to some problems with the various design units. For this reason, at the end of the first test phases were introduced restrictions on the maximum flight speed, angle of attack, etc..

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

Project C-37 / Su-47 "Berkut" allow Russian aircraft manufacturers to test several important ideas and gather a lot of information about the aircraft with forward-swept wing. Received information about the nature and flow behavior of the aircraft with CBS on different flight modes allow domestic aviation science to close some gaps in theories. By the middle of the last decade, only a prototype of the "Berkut" has fulfilled all the planned flight program and got to the parking lot.

It should be noted, that after the main test program, the Su-47 had a chance to participate in yet other research activities. Since it was the only domestic airplane, having dimensions fighter, but equipped with internal gruzootseke, he was chosen as the platform for developing some of the elements of the future fighter T-50 (PAK FA program). AT 2006-2007 years of "Berkut" has a new gruzootseke, designed by the T-50. The purpose of this revision was to check the flaps and internal equipment compartment on the performance in real flight conditions. Su-47 flew about so gruzootseke 70 flight with open wings. Interesting, that the flaps of the first test compartment opened and recorded still on earth. AT 2008-2009 Years of Su-47 has an updated amount of payload with the mechanisms of opening the valves. AT 2009 year was carried out 25 Flight with opening flaps.

As far as, The Su-47 was used as a stand not only for gruzootseke wings. In the new test under the program PAK FA, he was carrying the weight simulators promising missiles. Information, obtained during test flights of new aircraft Su-47, actively used in the final stages of creating gruzootseke promising fighter T-50.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

unambiguous result

The first prototype of the aircraft C-37-1 began to build two decades ago, flew in 1997 year and is actively tested before the first half of the two-thousand years. Aircraft design with forward-swept wing is closed a few years ago. Experimental aircraft showed all, I was capable of and allowed to collect a maximum of necessary information. Furthermore, Su-47, which is only mistakenly considered a fighter of the fifth generation, It became a flying laboratory for testing new technologies, Associated with Armed perspective planes.
Participation of the aircraft in critical experiments and tests partly bad impact on potential public shows. Su-47 regularly participated in the air show in Zhukovsky until the middle of the last decade, but I never got on static display. All the demonstrations were to demonstration flights. Experts and the public interest has not been able to inspect the vicinity of interesting, but not having almost no practical plane prospects.

Despite the long-standing project completion, It has not yet been an ongoing debate about the pros and cons or prospects as a Su-47, and the entire class of aircraft equipment with forward-swept wing. Time after time, we discussed the pros and cons of CBS, aircraft projects with him, etc.. There is no consensus about the prospects of the aircraft, like the Su-47, there is still no. As for the "Berkut" the project, it should be considered successful. Although the Su-47 and did not become the basis for a promising fighter, superior in its characteristics all the modern technology, did all the, what was intended. C-37 / Su-47 was created as an experimental aircraft for the development of new technologies. For this task he coped brilliantly, and the role of modern combat aircraft with unique characteristics must take other developments.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

materials

The airframe manufactured with extensive use of composite materials (KM). for example, aircraft wing made of composite carbon fiber-based enterprise "CVTs" Technology "".

Application of advanced composites provides increased load ratio 20-25 %, resource - in 1,5-3,0 times, materials to utilization 0,85, lowering labor costs for manufacturing parts 40-60 %, and obtaining the desired thermal and electronic characteristics. At the same time experiments, conducted in the United States under the F-22A, show less survivability of structures made of carbon fiber, compared with designs, made of aluminum and titanium alloys, that can withstand the load at high pressure and stalling.

Design

"Golden Eagle" is formed on the aerodynamic configuration "longitudinal integral triplane" forward-swept wing (CBS). The wing with the fuselage is blended, forming a single carrier system. By layout features include advanced wing nodules, under which placed unregulated air intakes engines, having a sectional shape, close to a range of sectors.

fighter wing has developed root portion (about 75 °) Sweep angle and interchangeable (about 10 °) on the front edge and smoothly mating with her arm portion forwardswept (the leading edge - of the order of 20 °). The wing is equipped with flaperons, occupying more than half the span, and ailerons. All-moving canards (PGO) swing around 3,5 m has a trapezoidal shape. Its angle of sweep of the leading edge - of the order of 50 °. Rear horizontal tail relatively small area also holds tselnopovorotnym, with a sweep angle of the leading edge of the order of 75 °.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

Avionics

The project was supposed to, that the machine will apply the most advanced avionics - digital multichannel desu (on the first plane - Analog), automated integrated control system, navigation system, which includes INS laser gyro, combined with satellite navigation and a "digital map", already found application in such machines, as Su-30MKI, Su-34 and Su-27M. It was planned to equip an integrated life support system and the bailout of the new generation crew.

To control airplane, and as to the Su-37, probably, applied side malohodovaya control stick and throttle strain (the first aircraft central RC).

Location and size of antennas avionics designers suggest striving to provide all-round visibility. Besides the main radar, housed in the nose fairing under orebryannym, Fighter has two rearview antenna, installed between the wing and the engine nozzles.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

weaponry

Of the Su-47 is an experimental. It was created for developing airframe scheme, layout solutions and materials, so the arms could not be accommodated without additional modernization of aircraft. During the development of Sukhoi PAK FA, Glider Su-47 has been upgraded and received a bomb bay, experience of creation of which was subsequently applied to the PAK-FA.

During the development planned, that "the main fire" fighter, obviously, will be managed by medium-range missiles of the RVV-AE, with active radar homing system the final and optimized for placement in cargo compartments of aircraft (they have a low aspect ratio wing and folding grid fin). SPA "Vympel" has announced a successful flight tests of the Su-27, an improved version of this missile, equipped with a sustainer ramjet engine. The new modification has increased range and speed.

Importance of arming aircraft must have and missiles "air-to-air" short-range. At the MAKS-97 demonstrated a new missile of this class, K-74, created on the basis of SD-P 73, and differs from the latter an improved system thermal homing, having an angle target capture, increased from 80-90 ° to 120 °. Applying new thermal homing (TGS) also made it possible to increase the maximum range of hitting the target at 30 % (to 40 km).

probably, as a part of on-board armament promising fighters will be saved and a 30-millimeter cannon GS-30-1.

planned, that as well as other domestic multipurpose aircraft - Su-30MKI, Su-35 and Su-37, New vehicles will be wear and impact weapons - precision SD and KAB "air-land" class to destroy ground and surface targets, as well as the enemy's radar.

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

Tactic-technical characteristics of the Su-47 Berkut

Su-47 crew

– 1 human

The dimensions of the Su-47

– Length: 22,6 m
– Wingspan: 16,7 m
– Height: 6,4 m
– wing area: 56 m²
– area PGO: 5,7 m²

All Su-47

– empty weight: 19500 kg
– Normal takeoff weight: 26500 kg
– Maximum takeoff weight: 38500 kg
– fuel weight: 12000 kg

Engine Su-47

– engine's type: Turbofan with afterburner
– Model: P 179-300 (for serial aircraft), D-30F6 (for prototype)

pull

– maximum: 2 × 12400 kgf (P 179-300)
– Furious at: 2 × 17500 kgf (P 179-300) 2 × 15500 (D-30F6)

The rate of the Su-47

– Limit on the height of the speed: 2500 kmh (limited to 900 km / h in relation to the breaking load on the wing and center section)
– The speed limit near the ground: 1400 kmh
– Besforsazhny speed limit: more 1200 kmh (M = 1)

The range of the Su-47 flight

– Ferry (from 2 PTB): 5500 km
– At subsonic speeds: 4000 km
– At supersonic speed: 1600 km

Combat radius Su-47

– subsonic: 2000 km
– supersonic: 800 km

The duration of the flight of the Su-47

– 6,5 hours

Practical ceiling Su-47

– 20000 m

Takeoff run Su-47

– 90 m (opportunity to take off on a ballistic trajectory[7])

Thrust-to-weight ratio of the Su-47

– at maximum takeoff weight: 0,91 kg / kg
– during normal takeoff weight: 1,32 kg / kg

Weapon Su-47

– Small-pushechnoe: 1 × 30 mm cannon GS-30-1
– combat load:
– normal: 1000 kg (4 × P-77 + 4 × 9M100 (planned))
– maximum: 8000 kg

Of the Su-47 is an experimental. It was created for developing airframe scheme, layout solutions and materials, so the arms could not be accommodated without additional modernization of aircraft. During the development of Sukhoi PAK FA, Glider Su-47 has been upgraded and received a bomb bay, experience of creation of which was subsequently applied to the PAK-FA.

Photo Su-47 Berkut

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

 Su-47 Berkut Dimensions. Engine. The weight. story. Range of flight. Service ceiling

 

                          
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