The Su-29 sports aircraft was developed at the Sukhoi design bureau on the basis of the previous model. sports plane Su-26. The most significant difference between these machines is that the new machine had a two-seater cockpit.

The history of the creation of the Su-29

Many years of experience of designers have shown that many hours of pilot training are the basis for success in sports. For these reasons, in 1991, the designers of the Sukhoi Design Bureau began to create a new project that was supposed to provide training for sports pilots. Due to the fact that the new machine was designed in a two-seater version, this could reduce pilot training time and training costs. In addition to athletes, military pilots also polished their skills on this machine.

The Su-29 was ready a year after the start of the design. Such fast production can be explained by the fact that most of the systems and assemblies were borrowed from the previous version of the Su-26 sports aircraft. The main differences are noticeable in the fuselage layout, as another cockpit was added. The wingspan and body length were also increased by 40 centimeters. Compared with the Su-26, the new Su-29 became the heaviest by only 60 kilograms, this was achieved through the use of a large number of composite materials. Composite materials make up 60% of the entire structure of the apparatus. All this made it possible to have practically the same flight performance as well as a one-seater car.

Even before the plane took off, it was demonstrated at the world air show in Paris. The plane made its first flight at the end of the summer of 1991 at the Zhukovsky airfield. As for the factory flight tests, they were worked out simultaneously on three similar devices of this series. Factory tests were completed by the end of 1991 and were marked by very positive results. The car received its first sports experience in 1992 at the World Olympics in France, where it was noted by experts as a very good and promising model. Almost immediately after these competitions, the manufacturer received an order from the United States for the supply of 12 Su-29 aircraft. In total, about 50 vehicles of this class were delivered to other countries of the world.

The Su-29 aircraft received a quality certificate of the IAC type in July 94 of the year, and a year later it was allowed to operate as a training aircraft. In 1996, this aircraft was tested by experienced pilots of the Russian Air Force. The result of the tests was confirmation that the Su-29 aircraft can perform such complex figures as corkscrews of varying complexity. But the most important quality characteristic was that the pilots felt comfortable on this aircraft and were able to control every moment of the flight. The aircraft received all these characteristics due to the painstaking and thoughtful work of the designers of the Sukhoi bureau.

The aircraft can be controlled by one pilot, while the aircraft corresponds to the flight characteristics of the Su-26. When creating an aircraft of the Su-29 type, the design of a single-seat machine took place in parallel, which received the designation Su-29T, and after a while new apparatus renamed Su-31.

Design features of the Su-29

An aircraft of the Su-29 type has power plant, which is represented by one nine-cylinder screw engine producing 360 horsepower. The M-14P engine drives the MTV-3 three-blade propeller, which is made to order in Germany. This sports car has a fairly low weight - only 735 kilograms empty, and Weight Limit, which the plane can lift into the air, is 1205 kilograms.

The Su-29 aircraft can fly at a speed of more than 400 km / h, the speed of the aircraft during flight and landing is only 120 km / h. The aircraft can be effectively operated at altitudes up to 4 kilometers. A special feature during takeoff is that the aircraft requires a runway of 250 meters.

As for the onboard equipment, it can be quite different depending on the wishes of the customer. For example, an aircraft can be equipped with foreign-made navigation systems. In addition, a GPS system can be installed on this machine.

The aircraft was manufactured at the Dubinsky aircraft plant, which had quite large orders from different countries the world. Modifications were also made that differed in the type of ejection seats. One of the modifications was specially developed by order of Argentina for the Air Force.

Su-29 characteristics:

Modification
Wingspan, m	8.20
Aircraft length, m	7.29
Aircraft height, m	2.89
Wing area, m2	12.20
Weight, kg
empty plane	735
normal takeoff	860
maximum takeoff	1204
Internal fuel, kg	207
engine's type	1 PD M-14PT
Power, h.p.	1 x 355
Maximum speed, km / h
dives, km / h	450
horizontal flight	385
Practical range, km	1200
Practical ceiling, m	4000
Max. operational overload	12
Crew, people	1-2

LPI program

Appearance of the Su-29:

The creation of fourth-generation fighters began in the Soviet Union in response to information about a similar program launched in the United States in 1966. The American program FX (Fighter Experimental) provided for the creation of a successor to the tactical fighter F-4C Fantom II. Over the course of several years, the concept of the fighter was revised and refined, and in 1969, McDonnell-Douglas began designing a new fighter, indexed F-15. According to the results of the competition, the F-15 project was recognized as the winner, bypassing the projects of the North American, Lockheed and Republican firms. In December 1969, the firm was awarded a contract for the construction of prototype aircraft, and on July 27, 1972, the first flight was carried out by the YF-15 prototype. After the successful completion of the tests, the production of the first production F-15A Eagle machines began, which entered service with the US Air Force in 1974.

Fighters of the FX program.

The FX program was closely followed in the USSR as well. Information leaking into the periodicals, as well as coming through intelligence channels, made it possible to create a fairly accurate idea of ​​the scheme, characteristics and capabilities of a potential competitor. Unsurprisingly, the initial design assignment for the 4th generation fighter involved the development of an aircraft similar to the F-15. This "Advanced Frontline Fighter" (PFI) program was issued by the Ministry aviation industry the three main Soviet design bureaus dealing with fighters - P.O. Sukhoi, A.I. Mikoyan and A.S. Yakovlev - in 1970. Almost immediately, during the discussion of the program, representatives of the Mikoyan Design Bureau put forward a proposal to create a light fighter in addition to the heavy fighter. According to the speakers, the USSR Air Force fighter aircraft fleet should have consisted of 1/3 heavy fighters and 2/3 light fighters. A similar concept was being worked out in the United States at the same time, when, in addition to the F-15 heavy fighter, development of the F-16 and F-17 light fighters continued. The proposal was received very ambiguously, nevertheless it was accepted. The PFI program was divided into programs for the creation of a "heavy front-line fighter" (TFI) and a "light front-line fighter" (LFI).
All three design bureaus began developing aircraft for both programs. They received the designations: Su-27, MiG-33 and Yak-47 (TFI program) and Su-29, MiG-29 and Yak-45I (LFI program).

In 1971, the first tactical and technical requirements (TTT) of the Air Force for the promising light front-line fighter LFI were formed. By this time, the details of the ADF (Advanced Day Fighter) program, which started in the United States in the late 60s, became known in the USSR. The requirements of this program were taken as the basis for the development of TTT, while it was envisaged that the Soviet fighter should surpass the American counterpart in a number of parameters by 10%. In accordance with the TTT, a light, cheap fighter with high maneuverability and thrust-to-weight ratio was required. The main characteristics that, according to the Air Force, the new fighters should have were:
- maximum flight speed at an altitude of over 11 km - 2500 ... 2700 km / h;
- maximum flight speed at the ground - 1400 ... 1500 km / h;
- maximum rate of climb at the ground - 300 ... 350 m / s;
- practical ceiling - 21 ... 22 km;
- flight range without PTB near the ground - 800 km;
- flight range without PTB at high altitude - 2000 km;
- maximum operational overload - 8 ... 9;
- acceleration time from 600 km / h to 1100 km / h - 12 ... 14 s;
- acceleration time from 1100 km / h to 1300 km / h - 6 ... 7 s;
- starting thrust-to-weight ratio - 1.1 ... 1.2;
- armament: 23-30 mm cannon, 2 medium-range missiles, 2-4 short-range missiles.
The main combat missions of the LFI were defined as:
- destruction of enemy fighters in close air combat using guided missiles and cannons;
- intercepting air targets at long range when guided from the ground or autonomously using a radar sighting system and conducting air combat at medium distances using guided missiles;
- cover for troops and objects production infrastructure from an attack from the air;
- counteraction to enemy air reconnaissance means;
- conducting aerial reconnaissance.
It was proposed to include in the armament of the new fighter the K-25 medium-range missiles, which were being created at that time at the Vympel plant according to the American AIM-7E Sparrow missile defense scheme, or similar Soviet K-23 missiles used on the 3rd generation fighters, as well as K-60 close air missiles and a promising 30 mm double-barreled cannon.
The preliminary design of the Su-29 aircraft, generally satisfying the TTT of the Air Force to the LFI, was developed at the P.O. Sukhoi Design Bureau in the first half of 1972.The project, which received the code name T11-1, was a single-engine monoplane with a forward horizontal tail and vertical tail, set to 2/3 of the wingspan with a significant camber angle. The engine air intake was located under the fuselage.
Normal takeoff weight aircraft was estimated at 10,000 kg. In accordance with the given starting thrust-to-weight ratio, the thrust of the engines should have been 11000-12000 kgf. In the early 70s. of the developed by-pass turbojet engines, AL-31F, D-30F-9 and R59F-300 had a similar thrust. The thrust-to-weight ratio with the AL-31F engine was considered insufficient, although the concept of using one type of engine on both heavy and light fighters was tempting. The D-30F-9, although it possessed a greater thrust, was heavier and did not fit well into the structure of the hull. As a result, the R59F-300 engine was chosen for installation on the Su-29, which at that time was being developed at the Soyuz MMZ under the leadership of the general designer SK Tumansky.
The fighter's armament consisted of two K-25 medium-range missiles and two K-60 melee missiles. The ammunition load of the built-in double-barreled gun AO-17A of 30 mm caliber was 250 rounds.

In October 1972, a meeting of the Joint Scientific and Technical Council (STC) of the Ministry of Aviation Industry (MAP) and the Air Force was held, at which the state of work on promising fighters within the framework of the LPI program was considered. Presentations were made by representatives of all three design offices... G.E. Lozino-Lozinsky reported on behalf of the Mikoyan Design Bureau, who presented to the commission a draft of the MiG-29 fighter (still in the version of the classic layout, with a high-located trapezoidal wing, side air intakes and a single-fin tail unit). O.S. Samoilovich from the Sukhoi Design Bureau presented an advanced design of the Su-29 at the NTS. The Yakovlev Design Bureau was represented by the General Designer A.S. Yakovlev with lung project fighter Yak-45I (based on the light attack aircraft Yak-45). Yakovlev's project was a development of the Yak-33 supersonic interceptor scheme with a variable sweep wing and engine nacelles with frontal air intakes installed at the break in its leading edge.

Light fighters submitted to the LFI program advance design competition in 1972

The main characteristics of fighters:

The second meeting of the NTS took place three months later. The composition of the participants has not changed, however, the Mikoyan Design Bureau presented in principle new project the MiG-29 fighter, now made according to the integrated circuit and having a smaller dimension (normal take-off weight is 12800 kg). As a result of two meetings of the NTS, the Yakovlev Design Bureau dropped out of the competition due to the need to finalize the aerodynamic scheme to ensure the safety of the fighter's continued flight in the event of failure of one of the engines installed on the wing, while the other two participants had to finalize their projects and clarify the design characteristics.
By the time of the third meeting of the NTS under the LFI program in April 1973, the competition for a heavy front-line fighter ended with the victory of the Su-27 project. This fact largely influenced the result of the second competition. The Ministry of Aviation Industry considered that it was wrong to concentrate the development of both promising fighters in one design bureau, which was also overloaded with other equally important projects, and gave the victory to the MiG-29 project. Officially, the reason for the refusal of the Su-29 was the problems with the suction of stones and debris from the runway at the time of takeoff (on the MiG-29 this problem was solved using separate air channels), the worst avionics, problems with the development of the R59F-300 engines, as well as the fact that normal takeoff weight in the process of specifying the characteristics has grown to 10,800 kg. Despite this, the Su-29 had its advantages: its cost was 20% less than its competitor, and its maneuverability and climb rate were higher.
In any case, the Su-29 project was closed, and the main forces of the Sukhoi Design Bureau were directed to the development of the Su-27. The developments on a light single-engine fighter with PGO were used to create the C-37 project in the late eighties.

The main characteristics of the Su-29:

Full length - 13.66 m
Wingspan - 7.04 m
Wing area -17.5 m2
Power plant - 1 x TRDDF R59F-300
Takeoff engine thrust:
- afterburner - 12500 kgf
- maximum - 8100 kgf
Takeoff weight:
- normal - 10800 kg
- reloading - 12100 kg
Empty weight - 6850 kg
Payload mass - 750 kg
Fuel weight - 3000 kg
Thrust-to-weight ratio - 1.16
Maximum speed:
- near the ground - 1500 km / h
- at altitude - 2550 km / h
Service ceiling - 22,000 m
Time to climb 18000 m - 2.5 min
Practical range without PTB:
- near the ground - 800 km
- at altitude - 2000 km
Maximum operational overload - 9
Takeoff run - 350 m
Run length - 500 m
Armament - 30mm AO-17A cannon (ammunition for 200 rounds), 2 K-25 missiles, 2 K-60 missiles

The single most important reason is the missiles on board.

When the Su-27 and MiG-29 appeared on the world stage in the 1980s, they represented a dramatic generational leap over the early Soviet fighters. Another such leap was missiles, which form the basis of their weapons.

Indeed, the R-73 short-range air-to-air missile and the R-27 medium-range missile, first installed on these aircraft, are still in service today. At the same time, the design of the R-27 proved to be particularly successful, being suitable for constant modernization. What is the secret of her longevity?

In 1974, the Central Committee of the CPSU decided to start developing the fourth generation of fighters - the MiG-29 and Su-27. As a consequence of this decision, the Vympel Design Bureau began developing the R-27 rocket (whose prototype was designated K-27).

According to the original plan, there were two variants of the R-27 - the "light" K-27A for the MiG-29 with a shorter range and the "heavy" K-27B with an increased range for the Su-27. As a result, a modular propulsion system was developed for the rocket.

In accordance with the Soviet trend of the simultaneous development of missiles with radar and infrared ranging, a modular guidance system was developed for the R-27. This will come in handy later, when it appears whole line variants of the R-27 with different systems homing.

Another interesting design solution was the butterfly-shaped steering surfaces located in the center of the rocket. At first, they caused a number of complaints: some designers defended the scheme previously installed on the R-23, where the steering surfaces were located in the tail of the rocket. This solution reduced air resistance at low angles of attack and was considered aerodynamically more perfect. However, as the priority was given to the modular design of the rocket, this decision was rejected, as the tail placement of the steering surfaces would jeopardize the modularity of the power plant itself.

Context

Su-27 - a copy of a US military aircraft?

Sina.com 11/23/2017

Su-27 continue to fall

BBC Russian Service 10.06.2016

How the MiG-29 appeared in Yugoslavia

Kurir 24.04.2017

The truth about the MiG-29

Air & Space 08/26/2014

It is also interesting that the developers feared that even with the progress of Soviet technologies, the radars of the R-27 and its carrier aircraft would be inferior in their power and sensitivity to their Western counterparts. To prevent lagging, Soviet designers improved the missile's ability to lock onto a target after launch.

The earlier R-23 missile had an inertial target acquisition system, in which the missile was guided to a target after launch and could fly without blocking for some time, while its course was provided by an inertial navigation system. A significant improvement was achieved on the R-27 due to the carrier's ability to correct the missile's course using a radio transmitter.

During tests carried out in the late 1970s, K-27s were fired from MiG-23 fighters. The goal was only to check the telemetry, and the launches were made not on target. A thermal imaging rocket was also tested - it was fired at parachute targets. A working version of the K-27 with an infrared homing head was also released from the MiG-29 prototype in 1980, despite the fact that the carrier aircraft at that time did not have a radar.

State tests continued in the 1980s and ended in 1984. The K-27 missile was finally put into service in 1987 in two versions, under the names R-27R and R-27T. The letter "R" denoted a variant with a semi-active radar homing head, and "T" - a variant with a passive infrared RGS.

At the same time, the "heavy" version of the missile, the K-27B, originally intended for the Su-27, changed its designation to the K-27E. The letter "E" meant a higher energy power (and, therefore, an increased range). The development cycle turned out to be longer than that of the lighter counterpart due to a radical redesign of the Su-27 radar system in the hope of increasing its competitiveness. Complicated development and unforeseen problems associated with the increase in range.

The tests were finally completed in 1990, and the rocket was put into service under the names R-27ER and R-27ET - and its creators were awarded a state prize in 1991.

During the long development cycle of the R-27, the designers realized that the semi-active radar homing system (when the missile is aimed at the target with a radar signal from the carrier aircraft) could become outdated. Therefore, studies were carried out to create an active homing system. The homing heads of missiles of this type are equipped with their own radar, which allows it to independently irradiate the target without relying on the carrier aircraft.

This version was named R-27EA. It was developed in 1983, but the difficulties encountered in creating a compact radar in the seeker led to a delay. The final fate of the project is unknown, but most sources agree that the development finally stopped in the region of 1989 - when the design bureau switched to the R-77 rocket. Nevertheless, the work could well continue even after this moment, already as a private initiative.

In general, the main advantage of the R-27 series over its competitors is the increased range of the ER variant, reaching 130 kilometers. This is vastly superior to any of the AIM-7 Sparrow, its closest NATO counterpart. The main problem with the R-27 is the protracted development cycle, which allowed the American missiles to surpass it.

One example of such a delay is the P-27 intermediate course correction system. Although this feature was originally developed back in the 1970s, the rocket entered service only in 1987. By this time, American engineers had gradually made adjustments to the design of the AIM-7 missile, including a similar course correction system. The AIM-7P Block II rocket entered service in the same 1987 year.

The decision to stop further development of the rocket was probably also facilitated by the compromise nature of the steering surfaces. The R-77, the next generation active homing missile for the Soviet Air Force, was fitted with lattice fins for better maneuverability. Since achieve aerodynamic characteristics its descendant R-27 was still not destined, the addition of an active homing system was considered a waste of time and money.

In many ways, the R-27ER can be considered the swan song of the semi-automatic homing system. At the development stage, it became one of the most advanced missiles of its type due to its increased range and the possibility of intermediate course correction, but by the time it was accepted into service, the semi-automatic guidance itself began to become outdated. The United States launched its first self-homing missile, the AIM-120 AMRAAM, in 1991, just a year after the R-27ER.

Apparently, the Russian Air Force continues to use these missiles because their range is superior to the weakest possible adversaries, who are unlikely to have automatic homing missiles at their disposal. However, as it became clear in Syria, when a threat arises from an equal or practically equal enemy, the R-27 is abandoned in favor of the R-77.

Charlie Gao studied Political Science and Computer Science at Grinnell College and is an expert on defense and national security issues.

InoSMI materials contain assessments exclusively of foreign mass media and do not reflect the position of the InoSMI editorial board.

LPI program

Appearance of the Su-29:

The creation of fourth-generation fighters began in the Soviet Union in response to information about a similar program launched in the United States in 1966. The American program FX (Fighter Experimental) provided for the creation of a successor to the tactical fighter F-4C Fantom II. Over the course of several years, the concept of the fighter was revised and refined, and in 1969, McDonnell-Douglas began designing a new fighter, indexed F-15. According to the results of the competition, the F-15 project was recognized as the winner, bypassing the projects of the North American, Lockheed and Republican firms. In December 1969, the firm was awarded a contract for the construction of prototype aircraft, and on July 27, 1972, the first flight was carried out by the YF-15 prototype. After the successful completion of the tests, the production of the first production F-15A Eagle machines began, which entered service with the US Air Force in 1974.

Fighters of the FX program.

The FX program was closely followed in the USSR as well. Information leaking into the periodicals, as well as coming through intelligence channels, made it possible to create a fairly accurate idea of ​​the scheme, characteristics and capabilities of a potential competitor. Unsurprisingly, the initial design assignment for the 4th generation fighter involved the development of an aircraft similar to the F-15. This "Advanced Frontline Fighter" (PFI) program was issued by the Ministry of Aviation Industry to the three main Soviet design bureaus dealing with fighters - P.O. Sukhoi, A.I. Mikoyan and A.S. Yakovlev - in 1970. Almost immediately, during the discussion of the program, representatives of the Mikoyan Design Bureau put forward a proposal to create a light fighter in addition to the heavy fighter. According to the speakers, the USSR Air Force fighter aircraft fleet should have consisted of 1/3 heavy fighters and 2/3 light fighters. A similar concept was being worked out in the United States at the same time, when, in addition to the F-15 heavy fighter, development of the F-16 and F-17 light fighters continued. The proposal was received very ambiguously, nevertheless it was accepted. The PFI program was divided into programs for the creation of a "heavy front-line fighter" (TFI) and a "light front-line fighter" (LFI).
All three design bureaus began developing aircraft for both programs. They received the designations: Su-27, MiG-33 and Yak-47 (TFI program) and Su-29, MiG-29 and Yak-45I (LFI program).

In 1971, the first tactical and technical requirements (TTT) of the Air Force for the promising light front-line fighter LFI were formed. By this time, the details of the ADF (Advanced Day Fighter) program, which started in the United States in the late 60s, became known in the USSR. The requirements of this program were taken as the basis for the development of TTT, while it was envisaged that the Soviet fighter should surpass the American counterpart in a number of parameters by 10%. In accordance with the TTT, a light, cheap fighter with high maneuverability and thrust-to-weight ratio was required. The main characteristics that, according to the Air Force, the new fighters should have were:
- maximum flight speed at an altitude of over 11 km - 2500 ... 2700 km / h;
- maximum flight speed at the ground - 1400 ... 1500 km / h;
- maximum rate of climb at the ground - 300 ... 350 m / s;
- practical ceiling - 21 ... 22 km;
- flight range without PTB near the ground - 800 km;
- flight range without PTB at high altitude - 2000 km;
- maximum operational overload - 8 ... 9;
- acceleration time from 600 km / h to 1100 km / h - 12 ... 14 s;
- acceleration time from 1100 km / h to 1300 km / h - 6 ... 7 s;
- starting thrust-to-weight ratio - 1.1 ... 1.2;
- armament: 23-30 mm cannon, 2 medium-range missiles, 2-4 short-range missiles.
The main combat missions of the LFI were defined as:
- destruction of enemy fighters in close air combat using guided missiles and cannons;
- intercepting air targets at long range when guided from the ground or autonomously using a radar sighting system and conducting air combat at medium distances using guided missiles;
- covering troops and industrial infrastructure from air attacks;
- counteraction to enemy air reconnaissance means;
- conducting aerial reconnaissance.
It was proposed to include in the armament of the new fighter the K-25 medium-range missiles, which were being created at that time at the Vympel plant according to the American AIM-7E Sparrow missile defense scheme, or similar Soviet K-23 missiles used on the 3rd generation fighters, as well as K-60 close air missiles and a promising 30 mm double-barreled cannon.
The preliminary design of the Su-29 aircraft, generally satisfying the TTT of the Air Force to the LFI, was developed at the P.O. Sukhoi Design Bureau in the first half of 1972.The project, which received the code name T11-1, was a single-engine monoplane with a forward horizontal tail and vertical tail, set to 2/3 of the wingspan with a significant camber angle. The engine air intake was located under the fuselage.
The normal take-off weight of the aircraft was estimated at 10,000 kg. In accordance with the given starting thrust-to-weight ratio, the thrust of the engines should have been 11000-12000 kgf. In the early 70s. of the developed by-pass turbojet engines, AL-31F, D-30F-9 and R59F-300 had a similar thrust. The thrust-to-weight ratio with the AL-31F engine was considered insufficient, although the concept of using one type of engine on both heavy and light fighters was tempting. The D-30F-9, although it possessed a greater thrust, was heavier and did not fit well into the structure of the hull. As a result, the R59F-300 engine was chosen for installation on the Su-29, which at that time was being developed at the Soyuz MMZ under the leadership of the general designer SK Tumansky.
The fighter's armament consisted of two K-25 medium-range missiles and two K-60 melee missiles. The ammunition load of the built-in double-barreled gun AO-17A of 30 mm caliber was 250 rounds.

In October 1972, a meeting of the Joint Scientific and Technical Council (STC) of the Ministry of Aviation Industry (MAP) and the Air Force was held, at which the state of work on promising fighters within the framework of the LPI program was considered. Representatives of all three design bureaus made reports. G.E. Lozino-Lozinsky reported on behalf of the Mikoyan Design Bureau, who presented to the commission a draft of the MiG-29 fighter (still in the version of the classic layout, with a high-located trapezoidal wing, side air intakes and a single-fin tail unit). O.S. Samoilovich from the Sukhoi Design Bureau presented an advanced design of the Su-29 at the NTS. The Yakovlev Design Bureau was represented by the General Designer A.S. Yakovlev with the project of the Yak-45I light fighter (based on the Yak-45 light attack aircraft). Yakovlev's project was a development of the Yak-33 supersonic interceptor scheme with a variable sweep wing and engine nacelles with frontal air intakes installed at the break in its leading edge.

Light fighters submitted to the LFI program advance design competition in 1972

The main characteristics of fighters:

The second meeting of the NTS took place three months later. The composition of the participants did not change, however, the Mikoyan Design Bureau presented a fundamentally new project of the MiG-29 fighter, now made according to an integrated circuit and having a smaller dimension (normal takeoff weight 12,800 kg). As a result of two meetings of the NTS, the Yakovlev Design Bureau dropped out of the competition due to the need to finalize the aerodynamic scheme to ensure the safety of the fighter's continued flight in the event of failure of one of the engines installed on the wing, while the other two participants had to finalize their projects and clarify the design characteristics.
By the time of the third meeting of the NTS under the LFI program in April 1973, the competition for a heavy front-line fighter ended with the victory of the Su-27 project. This fact largely influenced the result of the second competition. The Ministry of Aviation Industry considered that it was wrong to concentrate the development of both promising fighters in one design bureau, which was also overloaded with other equally important projects, and gave the victory to the MiG-29 project. Officially, the reason for the refusal of the Su-29 was the problems with the suction of stones and debris from the runway at the time of takeoff (on the MiG-29 this problem was solved using separate air channels), the worst avionics, problems with the development of the R59F-300 engines, as well as the fact that normal takeoff weight in the process of specifying the characteristics has grown to 10,800 kg. Despite this, the Su-29 had its advantages: its cost was 20% less than its competitor, and its maneuverability and climb rate were higher.
In any case, the Su-29 project was closed, and the main forces of the Sukhoi Design Bureau were directed to the development of the Su-27. The developments on a light single-engine fighter with PGO were used to create the C-37 project in the late eighties.

The main characteristics of the Su-29:

Full length - 13.66 m
Wingspan - 7.04 m
Wing area -17.5 m2
Power plant - 1 x TRDDF R59F-300
Takeoff engine thrust:
- afterburner - 12500 kgf
- maximum - 8100 kgf
Takeoff weight:
- normal - 10800 kg
- reloading - 12100 kg
Empty weight - 6850 kg
Payload mass - 750 kg
Fuel weight - 3000 kg
Thrust-to-weight ratio - 1.16
Maximum speed:
- near the ground - 1500 km / h
- at altitude - 2550 km / h
Service ceiling - 22,000 m
Time to climb 18000 m - 2.5 min
Practical range without PTB:
- near the ground - 800 km
- at altitude - 2000 km
Maximum operational overload - 9
Takeoff run - 350 m
Run length - 500 m
Armament - 30mm AO-17A cannon (ammunition for 200 rounds), 2 K-25 missiles, 2 K-60 missiles

What made the Soviet Su-27 and MiG-29 fighters the most dangerous?

MiG-29 kyiveuromarathon

When the Su-27 and MiG-29 appeared on the world stage in the 1980s, they represented a dramatic generational leap over the early Soviet fighters. Another such leap was missiles, which form the basis of their weapons.

Indeed, the R-73 short-range air-to-air missile and the R-27 medium-range missile, first installed on these aircraft, are still in service today. At the same time, the design of the R-27 proved to be particularly successful and suitable for constant modernization. What is the secret of her longevity?

In 1974, the Central Committee of the CPSU decided to start developing the fourth generation of fighters - the MiG-29 and Su-27. As a consequence of this decision, the Vympel design bureau began developing the R-27 rocket (whose prototype was designated K-27).

Related news

According to the original plan, there were two variants of the R-27 - the "light" K-27A for the MiG-29 with a shorter range and the "heavy" K-27B with an increased range for the Su-27. As a result, a modular propulsion system was developed for the rocket.

In accordance with the Soviet trend of the simultaneous development of missiles with radar and infrared ranging, a modular guidance system was developed for the R-27. This will come in handy later, when a number of R-27 variants with various homing systems appear.

Another interesting design solution was the butterfly-shaped steering surfaces located in the center of the rocket. At first, they caused a number of complaints: some designers defended the scheme previously installed on the R-23, where the steering surfaces were located in the tail of the rocket. This solution reduced air resistance at low angles of attack and was considered aerodynamically more perfect. However, given the priority given to the modular design of the rocket, this decision was rejected as the tail-mounted steering surfaces would compromise the modularity of the power plant itself.

Su-27 kyiveuromarathon

It is also interesting that the developers feared that even with the progress of Soviet technologies, the radars of the R-27 and its carrier aircraft would be inferior in power and sensitivity to their Western counterparts. To prevent lagging, Soviet designers improved the missile's ability to lock onto a target after launch.

The earlier R-23 missile had an inertial target acquisition system, in which the missile was guided to a target after launch and could fly without blocking for some time, while its course was provided by an inertial navigation system. On the R-27, a significant improvement was achieved thanks to the ability of the carrier aircraft to correct the missile's course using a radio transmitter.

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During tests carried out in the late 1970s, K-27s were fired from MiG-23 fighters. The goal was only to check the telemetry, and the launches were made not on target. A thermal imaging rocket was also tested - it was fired at parachute targets. A working version of the K-27 with an infrared homing head was also released from the MiG-29 prototype in 1980, despite the fact that at that time there was no radar on the carrier aircraft.

State tests continued in the 1980s and ended in 1984. The K-27 missile was finally put into service in 1987 in two versions, under the names R-27R and R-27T. "R" was the version with a semi-active radar homing head, and "T" was the version with passive infrared radar.

At the same time, the "heavy" version of the missile, the K-27B, originally intended for the Su-27, changed its designation to the K-27E. The letter "E" meant a higher energy power (and, therefore, an increased range). The development cycle turned out to be longer than that of the lighter counterpart, due to a radical redesign of the Su-27 radar system in the hope of increasing its competitiveness. Complicated development and unforeseen problems associated with the increase in range.

The tests were finally completed in 1990, and the rocket was put into service under the names R-27ER and R-27ET - and its creators were awarded a state prize in 1991.

R-27ET Aviaru.rf

During the long development cycle of the R-27, the designers realized that the semi-active radar homing system (when the missile is aimed at the target with a radar signal from the carrier aircraft) could become outdated. Therefore, studies were carried out to create an active homing system. The homing heads of missiles of this type are equipped with their own radar, which allows it to independently irradiate the target without relying on the carrier aircraft.

This version was named R-27EA. It was developed in 1983, but the difficulties encountered in creating a compact radar in the seeker led to a delay. The final fate of the project is unknown, but most sources agree that the development finally stopped in the region of 1989 - when the design bureau switched to the R-77 rocket. Nevertheless, the work could well continue even after this moment, already as a private initiative.

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In general, the main advantage of the R-27 series over its competitors is the increased range of the ER variant, reaching 130 kilometers. This is vastly superior to any of the AIM-7 Sparrow, its closest NATO counterpart. The main problem with the R-27 is the protracted development cycle, which allowed the American missiles to surpass it.

One example of such a delay is the P-27 intermediate course correction system. Although this feature was originally developed back in the 1970s, the rocket entered service only in 1987. By this time, American engineers had gradually made adjustments to the design of the AIM-7 missile, including a similar course correction system. The AIM-7P Block II rocket entered service in the same 1987 year.

The decision to stop further development of the rocket was probably also facilitated by the compromise nature of the steering surfaces. The R-77, the next generation active homing missile for the Soviet Air Force, was fitted with lattice fins for better maneuverability. Since it was still not destined to achieve the aerodynamic characteristics of its descendant R-27, the addition of an active homing system was considered a waste of time and money.

P-77 Wikipedia

In many ways, the R-27ER can be considered the swan song of the semi-automatic homing system. At the development stage, it became one of the most advanced missiles of its type due to its increased range and the possibility of intermediate course correction, but by the time it was taken into service, the semi-automatic guidance itself began to become outdated. The United States launched its first self-homing missile, the AIM-120 AMRAAM, in 1991, just a year after the R-27ER.

Apparently, the Russian Air Force continues to use these missiles because their range is superior to the weakest possible adversaries, who are unlikely to have automatic homing missiles at their disposal. However, as it became clear in Syria, when a threat arises from an equal or practically equal enemy, the R-27 is abandoned in favor of the R-77.

Charlie Gao

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