irandefender
01-14-2006, 10:35 AM
salam
Does any one know about the new SU-27s that iran bought.
please read the article below I underlined iran in it.
thank you
http://www.jetfly.hu/rovatok/repules/katonai/hirek/su27crash_050928/foto_su27o.jpg
http://mfinfo.ru/files/2-su-27.jpg
http://www.globalaircraft.org/photos/planephotos/su-27_1.jpg
The Sukhoi Su-27
v1.0.2 / 01 jun 02 / greg goebel / public domain
* While the Russia that has emerged from the ruins of the old Soviet empire remains disorganized and shaky, the Russian military still retains some impressive weapons. One of the more impressive is the Sukhoi Su-27 fighter, a large combat aircraft that is one of the mainstays of Russian air power. This document describes the history and details of the Su-27.
[1] ORIGINS / SUKHOI T10
* In 1969, the United States Air Force (USAF) selected the McDonnell Douglas F-15 as the winner of the service's "Fighter Experimental (FX)" program. Faced with a formidable new American threat, the Soviet government immediately issued a request for a new fighter of their own to match the F-15, under the designation "Perspektivnyi Frontovi Istrebitel (PFI / Prospective Frontal Fighter)". The program was also apparently referred to as the "anti-F-15".
The PFI was specified as a long-range interceptor to replace older aircraft of that category, such as the Tupolev Tu-128 "Fiddler", the Sukhoi Su-15 "Flagon", and the Yak-28P "Firebar". As a secondary requirement, it was to be used as an escort for long-range strike aircraft such as the Su-24 "Fencer", or as a long-range intruder to attack Western air assets such as tankers or airborne warning & control systems (AWACS) deep in hostile territory.
The PFI requirements specified an agile aircraft with a top speed of 1,450 KPH (783 knots); a combat radius of 1,700 kilometers (916 nautical miles) at high altitude and 500 kilometers (270 nautical miles) at low altitude; and an operational ceiling of 18,300 meters (60,000 feet). The PFI was to be able to operate from what the Red Air Force (VVS) called a "Third Class Airfield", with a runway length of 1,200 meters (3,940 feet).
The Mikoyan and Sukhoi design bureaus (OKBs) both began work on the PFI specification. The Yakovlev OKB also initiated work on the requirement, but dropped out to pursue the Yak-141 vertical takeoff fighter. The Sukhoi design team was led by Yevgeny Ivanov and his deputy, Oleg Samolovich, with inputs from OKB Director General Pavel Sukhoi.
Following aerodynamic information provided by the TsAGI (Tsentral'nyi Aerogidrodynamichesky Institut / Central Aerodynamic & Hydrodynamic Research Institute), both the Sukhoi and MiG OKBs designed aircraft with a twin-finned, high-winged, tailed-delta configuration and using a new armament and fire-control system being implemented by other design bureaus. The main armament was to be the "K-25" missile, which was apparently similar to the US Sparrow, but in fact never reached production.
It soon became obvious that the agility and range requirements of the PFI specification were incompatible, and so, under the urging of MiG OKB Director General Artem Mikoyan, the PFI specification was split into "Logiky PFI (LPFI / Lightweight PFI)" and "Tyazholyi PFI (TPFI / Heavy PFI)" specifications.
This also mirrored American thinking, since the US Air Force had followed their F-15 program with a relatively low-cost "lightweight fighter" effort that resulted in the F-16 Fighting Falcon.
One of the designs the Mikoyan OKB had investigated proved suitable for the LPFI specification, and became the Mikoyan "MiG-29". The Sukhoi design proved a match for the HPFI specification, and was designated "T10", since it was the tenth delta ("Teugoinyi / Triangular") winged aircraft designed by the Sukhoi OKB.
The T10 was a big aircraft, with large volume for carrying fuel and systems, and its elegantly-curved wing was blended into the fuselage to improve lift. Long leading-edge root extensions (LERX) were fitted to allow good handling at high angles of attack. The twin fins provided maximum controllability and directional stability.
The T10 was a twin-engined aircraft, initially fitted with Saturn-Lyulka AL-21F-3 engines providing 11,200 kilograms (24,700 pounds) thrust each, with the intakes under the wing roots. The first T10, designated "T10-1" or "Blue 10", flew on 10 May 1977, with Sukhoi's chief test pilot, General Vladimir Ilyushin, at the controls.
Vladimir Ilyushin is the son of Sergei Ilyushin, who founded the Ilyushin OKB, but is a well-known and highly respected figure in his own right. The T10 was the 143rd aircraft he had piloted, including almost every Soviet type and even the B-25 Mitchell, the Cessna A-37, and the Northrop F-5E. Ilyushin was extremely pleased with the T10.
Blue 10 was immediately spotted by a US reconnaissance satellite, with NATO giving the new type the provisional name of "Ram-K", since Western intelligence did not know the name for the secret Zhukovsky flight center and simply referred to it as "Ramenskoye", a nearby town. Some overimaginative analysts thought it had variable geometry wings, and a few years would pass before that myth would be discarded.
Other analysts suggested that it was a copy of a Western aircraft, much to the irritation of the aircraft's designers. To be sure, the Ram-K had features similar to those of Western fighters that had preceded it, but those Western fighters in some cases had features of various Soviet fighters that had preceded them in turn. In reality, similar aerodynamic and mission requirements tended to lead to similar design solutions.
To an extent, however, the "copycat" accusation wasn't based completely on snobbery, since the USSR, particularly in Stalin's day, pragmatically did not hesitate to borrow, copy, or steal useful foreign technologies. In fact, the MiG and Sukhoi OKBs occasionally accused each other of copying as well, though similarities between their respective efforts were inevitable, as they were working from the same TsAGI aerodynamic recommendations.
The second T10 prototype, the "T10-2", was lost on 7 May 1978, with the pilot, Yevgeny Soloviev, killed while ejecting. A total of four prototypes were built by the Sukhoi OKB in the bureau's workshops, while five more were built at the state factory at Komsomolsk between 1980 and 1982. The state factory also provided subassemblies for the four prototypes developed at the Sukhoi workshops. As Western intelligence learned more about the aircraft, it was given the name of "Flanker-A".
The prototypes varied in detail, with two of those developed at the bureau workshops featuring production "AL-31" engines. Two more prototypes were under construction when the decision was made to redesign the aircraft, as tests showed the T10 prototypes were not meeting performance specifications. As the T10 stood, it was no match for the American F-15.
* The redesigned aircraft was designated the "T10S", with the "S" optimistically standing for "Series". Roughly ten T10S prototypes were produced, with some of them built new and some rebuilt from T10 prototypes. Initial T10S prototypes were similar to the T10, with incremental changes progressing through the series to the final production configuration.
The development effort continued to have more than its share of troubles. The first T10S prototype, the "T10S-1", rebuilt from the "T10-7", first flew on 20 April 1981 with Vladimir Ilyushin as pilot but was lost due to a fuel system problem, with Ilyushin ejecting safely.
The second prototype, the "T10S-2", rebuilt from the T10-12, broke up in flight on 23 December 1981, killing its pilot, Alexander Komarov. Another prototype, the "T10S-7", was wrecked when the pilot, Nikolai Sadovnikov, tried only too successfully to duplicate the fatal last flight of the T10S-2, but Sadovnikov managed to get the aircraft back down on the ground even though it had lost much of its left wing. It turned out that the two accidents were caused by defective leading-edge flaps that broke away. The flaps were promptly redesigned.
After these nasty teething problems were resolved, the test pilots were wildly enthusiastic about the performance and handling of the T10S, particularly in comparison to the T10. Unfortunately, after the flight problems of the aircraft were generally resolved, manufacturing problems remained. The production aircraft, designated "Su-27", only began to enter service in small numbers in 1986. NATO gave the production aircraft the designation "Flanker-B".
* While the manufacturing problems were being resolved, some of the prototypes were being used to set flight records. The "P-42" was converted from the T10S-3 by stripping it of all unnecessary equipment, and was used to successfully challenge records held by the similarly stripped-down F-15 "Streak Eagle". The flights were performed by Sukhoi test pilots Viktor Pugachev and Nikolai Sadovnikov. One of the flights set a record climb to 15,000 meters (49,200 feet) in 70.33 seconds, breaking the Streak Eagle's record by seven seconds.
This was cause for satisfaction, given the rocky path of the aircraft's development, and encouraged believers that the efforts would pay off after all. Another prototype, the "T10S-10", was stripped down and modified to challenge the 500 kilometer (270 nautical mile) closed circuit speed record, but it appears it was never actually used in such an attempt.
BACK_TO_TOP
[2] SU-27 INTO SERVICE
* The production Su-27 clearly retained much of the look of the original T10, but the changes were visible and obvious. The most apparent change was the adoption of a larger wing that featured straight edges, replacing the curved wing of the T10. Other visible changes included:
Moving the twin vertical tailplanes from positions directly atop the engines to just outboard of the engines.
Moving the nosewheel back behind the cockpit to reduce engine ingestion of debris during ground operations, and for the same reason installing inlet debris screens that retract and extend along with the landing gear.
Twin ventral fins.
A new "stinger" fuselage extension protruding backwards behind the engine exhaust.
A large airbrake behind the cockpit.
Of course, the production Su-27 had armament and operational avionics systems. Armament included:
A 30 millimeter Gryazev-Shipunov GSh-30-1 cannon firing from the top of the right LERX from just behind the cockpit, with typical rates of fire of 1,500 rounds per minute, ammunition storage of 149 rounds, and titanium skinning on the airframe around the gun muzzle.
Two stores pylons on each wing, plus wingtip rails for air-to-air missiles (AAMs).
Two centerline stores pylons in tandem between the engines.
A stores pylon on the outer corner of each engine nacelle.
In mature production aircraft, the wingtip rails could be removed and replaced with Sorbtsiya electronic countermeasures (ECM) pods, and some aircraft had three stores pylons on each wing, along with the wingtip rails.
An infrared track-&-search (IRST) sensor was fitted just in front of the cockpit along with a laser rangefinder, and the nose accommodated the "N-001" long-range radar system. In later production Su-27s, the tail stinger extension accommodated the tail radome for the "SPO-15 (L-006) Beryoza" radar homing and warning system (RHAWS), as well 32 three-shot chaff-flare dispensers. The stinger possibly also stored a jammer system.
The Su-27 was built mostly of light aluminum alloy, with some stainless steel and titanium. Flight controls were hydraulically operated, with some pneumatic backup systems. The nosewheel retracted forward, as did the main gear, rotating 90 degrees to lie flat in the wing roots. The pilot sat high with a good view in a Zvezda "K-36DM" zero-zero ejection seat. The ejection seat provided a "NAZ-8" survival pack, with rescue radio / beacon, rations, flares, medical supplies, and an inflatable raft.
The Su-27 was powered by twin Saturn-Lyulka AL-31F afterburning turbofans, with 12,515 kilograms (27,600 pounds) afterburning thrust each. The AL-31F was very reliable by Soviet engine standards, with a good time between overhaul of 1,000 hours, and the airframe allowed easy access to the engines.
SU-27 (LATE PRODUCTION):
_____________________ _________________ _______________________
spec metric english
_____________________ _________________ _______________________
wingspan 14.7 meters 48 feet 3 inches
length 21.9 meters 72 feet
height 5.93 meters 19 feet 6 inches
empty weight 16,380 kilograms 36,100 pounds
max loaded weight 28,300 kilograms 62,400 pounds
maximum speed 2,500 KPH 1,550 MPH / 1,350 KT
service ceiling 18,000 meters 59,000 feet
combat radius 1,500 kilometers 930 MI / 810 NMI
_____________________ _________________ _______________________
* Su-27s began to perform mock intercepts of Western aircraft over the Barents Sea in early 1987, though at first they kept their distance. However, Norwegian F-16 pilots soon managed to get pictures of the type, and in September 1987 the crew of a Norwegian P-3 Orion ocean-patrol aircraft got a much closer view than they liked when an Su-27 clumsily clipped one of the P-3's propellers with its tail. Fortunately, both aircraft made it safely back home.
The Su-27 made its formal introduction to the West at the 1989 Paris Air Show, when Viktor Pugachev ran the aircraft through the now-famous "Cobra" maneuver, lifting the fighter to an angle of attack of over 90 degrees to its line of flight, causing abrupt deceleration until it nosed back down. The Cobra maneuver was apparently invented by another Sukhoi test pilot, Valerii Menitsky, as a flight-test exercise, but it became associated with Pugachev, it seems with his encouragement, and is also often called the "Pugachev maneuver" or "Pugachev Cobra". Few aviation experts believe that the Cobra maneuver has much combat utility, but it is undeniably a spectacular airshow trick.
It still shocked Western observers, since there were few or no Western aircraft that could perform the Cobra maneuver, and even though it may have been nothing more than a stunt, it demonstrated that the Su-27 was remarkably agile and very strongly built. However, observers noted that an Su-27 fully loaded for combat operations would not have anywhere near such capabilities, and is likely not all that capable as a close-in dogfighter, unsurprising for a big aircraft designed as a long-range interceptor.
The Su-27's agility is still impressive given its size, all the more so because the Su-27 is not a "dynamically unstable" design. Western designers have chosen to build maneuverable aircraft by designing them to be aerodynamically unstable, and then using advanced control systems to keep them in the air. Russian designers, preferring reliability and with less access to sophisticated avionics systems, opted for building a stable design and tweaking it for maximum maneuverability.
The Su-27 was, as mentioned, originally developed as a long-range "fighter interceptor" for the VVS and the Soviet air defense command (PVO), and was largely optimized for this role. Typical air-defense warload could be six "beyond visual range (BVR)" missiles and two or four short-range "dogfighting" missiles. While the Su-27's standard BVR missile, the "R-27" or "AA-10 Alamo" in its NATO codename, is regarded as inferior to the US AIM-120 AMRAAM, the standard dogfighting missile, the "Vympel R-73 / AA-11 Archer", is regarded one of the best in its class.
The R-73 has an "off-boresight" engagement capability, with the pilot cueing it to a target not directly in front of the aircraft with a helmet-mounted sight. The helmet-mounted sight can also be used to cue the IRST and laser rangefinder. While the US was developing AMRAAM at great expense and difficulty, the Soviets moved ahead with the R-73, and now the Americans are trying to catch up with the "AIM-9X Sidewinder" AAM.
The Su-27's electronics systems are less sophisticated than those of equivalent Western aircraft, and there are questions about their reliability, but the IRST has good tracking capability and the radar has excellent range, However, the radar does not have processing sophistication of Western counterparts. In the air-defense role, the Su-27 is designed to operate in conjunction with ground or air-based air-defense networks, a traditional Soviet practice, and the Su-27 has a datalink to allow it to perform intercepts "passively", without using its own radar.
Although the reliability of the Su-27's electronics may be uncertain, Russian partisans like to mock Western aircraft for their delicate mechanical nature and inability to operate off of rough airstrips. The rugged Su-27 was designed for such an environment and has no difficulty with it.
The large size of the Su-27 makes it useful as a strike aircraft, able to carry a wide range of munitions, but strike is a secondary mission for the basic Su-27. A reasonable judgement of the Su-27 would place it as superlative in its role as a fighter-interceptor, but probably not the equal of the F-15 as a multirole aircraft.
* By the way, the Su-27 has no formal name. Sukhoi says the aircraft is referred to as the "Azure Lighting", but it appears that it is generally called the "Crane", for its bent-necked appearance in flight. Some sources claim that Russian personnel occasionally even refer to it by its NATO codename, "Flanker".
BACK_TO_TOP
[3] TWO-SEAT SU-27UB / EXPORT SU-27SK / NAVAL SU-27K
* The Su-27 is a big and complicated aircraft that demands much of its pilots, and so during T10 and T10S development the Sukhoi OKB also worked on a two-seat operational trainer version. Due to the development difficulties discussed earlier, work on the two-seat version had to be set aside until the single-seat version was in production, and the first two-seat T10U prototype did not fly until March 1985, entering production and service as the Sukhoi "Su-27UB" a year or two later. While initial prototypes were built in Sukhoi OKB facilities in Moscow and Komsomolsk, full production was transferred to a state factory in Irkutsk.
The Su-27UB has a tandem seats under a single canopy, with the back seat stepped up above the front seat, providing the flight instructor in the back seat a good view of both the world in front of the aircraft and of what the trainee in the front seat is doing. Sukhoi engineers like to point out that the view from the rear seat is much superior to that from the rear of two-seat F-15s. This arrangement gives the Su-27UB an even more "crane-necked" appearance than the Su-27.
The second seat was accommodated by stretching the fuselage, and the vertical tailfins were increased in height slightly to compensate for the changed aerodynamics. The Su-27UB was designed to be fully combat capable. Addition of the second seat increased the weight of the aircraft by only about 1,120 kilograms (2,470 pounds) without reduction in fuel capacity, and aside from minor increases in runway requirement and comparably minor decreases in top speed, the Su-27UB's performance is very similar to that of the single-seat Su-27. Like the single-seat Su-27, early production Su-27UBs lack certain systems and features of late-production aircraft.
* The late-production single-seat Su-27 was used as the basis for the export variant, the "Su-27SK" (where "SK" stands for "Series Kommercial"). While the Su-27SK is externally all but identical to the Su-27, it has a downgraded system fit. A two-seat "Su-27UBK" was also built for the export market.
The Chinese were the first export customer for the Su-27, signing a contract in 1991 for 24 Su-27SKs and 2 Su-27UBKs, with initial deliveries in 1992. The Chinese bought another batch of exactly the same number and types of aircraft in 1995, and in 1996 the Chinese signed a license agreement to allow them to produce up to 200 Su-27s of their own. The license agreement apparently stipulates that they cannot export the type, which has the Chinese designation of "J-11".
In 1999, the Chinese ordered 40 "Su-30MKK" multirole combat aircraft, which feature a new radar and fire-control system. The Su-30 variants are discussed in more detail later. Initial delivery of a batch of ten took place in December 2000.
In the mid-1990s, Vietnam, not to be outdone by their ancient Chinese rival, also bought a number of Su-27s. Syria, Algeria, Iran, and Libya have expressed various levels of interest in obtaining the type as well. Of course, a number of Su-27s were "inherited" by some of the newly independent states, such as Belarus and Kazakhstan, created by the collapse of the USSR, but these were not export variants.
* The Soviet Navy had planned to acquire four fleet aircraft carriers, and so accordingly planned to build navalized versions of the MiG-29 and Su-27 for carrier operations.
Work on a navalized Su-27 actually went back almost to the very beginning of the design of the Su-27 family. T10S prototypes were modified to test features of navalized variants in an incremental fashion. The first test flights, from a dummy land-based carrier deck at Saki in the Crimea, featured aircraft fitted with with small canard wings for better low-speed approach, improved short takeoff performance, and enhanced combat maneuverability. Tests then went on to aircraft fitted with arresting gear, and then to tests of aircraft with carrier landing systems.
The carriers were to be fitted with "ski-jump" takeoff ramps, rather than catapults, and one of these navalized Su-27 prototypes made an initial takeoff from a land-based ski jump in August 1982. In operational practice, the aircraft was to take off a carrier deck by building up full thrust against a tilt-up blast deflector panel until the aircraft sheared restraints holding it down to the deck. The fighter would then accelerate up the deck and be tossed into the air with the ski-jump.
This unusual scheme was devised because the Soviets had no experience in building aircraft carrier catapults, and didn't want to delay introduction of the carriers while puzzling around with a new and demanding technology.
These modified prototypes led to specific prototypes for the navalized aircraft, designated "T10K". These aircraft had canards, an arresting hook, and carrier landing systems, as well as a retractable inflight refueling probe to allow the aircraft to take off with a reduced fuel load and top off in flight. However, they did not have the ruggedized landing gear required for carrier landings, and lacked folding wings. Pugachev flew the first T10K in August 1987, though that particular aircraft was lost in a mishap in 1988.
The production navalized "Su-27K" featured the required heavier landing gear and folding wings, with drooping outer ailerons and inner double-slotted flaps for low-speed carrier approaches. It began carrier trials on board the carrier TBILSI in November 1989, again with Pugachev at the controls, leading to introduction to formal carrier operations in September 1991.
A batch of 18 Su-27Ks were built in 1982 and 1983, though abandonment of plans for the four-carrier force in the aftermath of the collapse of the USSR meant that the need for building more Su-27Ks vanished. The KUZNETZOV, as the TBILISI had been renamed after the end of the Soviet Union, made a cruise in the Mediterranean in 1996, giving the Su-27K its first taste of ocean operations. NATO assigned the Su-27K the codename "Flanker-D", while the Sukhoi OKB calls the aircraft the "Su-33".
Does any one know about the new SU-27s that iran bought.
please read the article below I underlined iran in it.
thank you
http://www.jetfly.hu/rovatok/repules/katonai/hirek/su27crash_050928/foto_su27o.jpg
http://mfinfo.ru/files/2-su-27.jpg
http://www.globalaircraft.org/photos/planephotos/su-27_1.jpg
The Sukhoi Su-27
v1.0.2 / 01 jun 02 / greg goebel / public domain
* While the Russia that has emerged from the ruins of the old Soviet empire remains disorganized and shaky, the Russian military still retains some impressive weapons. One of the more impressive is the Sukhoi Su-27 fighter, a large combat aircraft that is one of the mainstays of Russian air power. This document describes the history and details of the Su-27.
[1] ORIGINS / SUKHOI T10
* In 1969, the United States Air Force (USAF) selected the McDonnell Douglas F-15 as the winner of the service's "Fighter Experimental (FX)" program. Faced with a formidable new American threat, the Soviet government immediately issued a request for a new fighter of their own to match the F-15, under the designation "Perspektivnyi Frontovi Istrebitel (PFI / Prospective Frontal Fighter)". The program was also apparently referred to as the "anti-F-15".
The PFI was specified as a long-range interceptor to replace older aircraft of that category, such as the Tupolev Tu-128 "Fiddler", the Sukhoi Su-15 "Flagon", and the Yak-28P "Firebar". As a secondary requirement, it was to be used as an escort for long-range strike aircraft such as the Su-24 "Fencer", or as a long-range intruder to attack Western air assets such as tankers or airborne warning & control systems (AWACS) deep in hostile territory.
The PFI requirements specified an agile aircraft with a top speed of 1,450 KPH (783 knots); a combat radius of 1,700 kilometers (916 nautical miles) at high altitude and 500 kilometers (270 nautical miles) at low altitude; and an operational ceiling of 18,300 meters (60,000 feet). The PFI was to be able to operate from what the Red Air Force (VVS) called a "Third Class Airfield", with a runway length of 1,200 meters (3,940 feet).
The Mikoyan and Sukhoi design bureaus (OKBs) both began work on the PFI specification. The Yakovlev OKB also initiated work on the requirement, but dropped out to pursue the Yak-141 vertical takeoff fighter. The Sukhoi design team was led by Yevgeny Ivanov and his deputy, Oleg Samolovich, with inputs from OKB Director General Pavel Sukhoi.
Following aerodynamic information provided by the TsAGI (Tsentral'nyi Aerogidrodynamichesky Institut / Central Aerodynamic & Hydrodynamic Research Institute), both the Sukhoi and MiG OKBs designed aircraft with a twin-finned, high-winged, tailed-delta configuration and using a new armament and fire-control system being implemented by other design bureaus. The main armament was to be the "K-25" missile, which was apparently similar to the US Sparrow, but in fact never reached production.
It soon became obvious that the agility and range requirements of the PFI specification were incompatible, and so, under the urging of MiG OKB Director General Artem Mikoyan, the PFI specification was split into "Logiky PFI (LPFI / Lightweight PFI)" and "Tyazholyi PFI (TPFI / Heavy PFI)" specifications.
This also mirrored American thinking, since the US Air Force had followed their F-15 program with a relatively low-cost "lightweight fighter" effort that resulted in the F-16 Fighting Falcon.
One of the designs the Mikoyan OKB had investigated proved suitable for the LPFI specification, and became the Mikoyan "MiG-29". The Sukhoi design proved a match for the HPFI specification, and was designated "T10", since it was the tenth delta ("Teugoinyi / Triangular") winged aircraft designed by the Sukhoi OKB.
The T10 was a big aircraft, with large volume for carrying fuel and systems, and its elegantly-curved wing was blended into the fuselage to improve lift. Long leading-edge root extensions (LERX) were fitted to allow good handling at high angles of attack. The twin fins provided maximum controllability and directional stability.
The T10 was a twin-engined aircraft, initially fitted with Saturn-Lyulka AL-21F-3 engines providing 11,200 kilograms (24,700 pounds) thrust each, with the intakes under the wing roots. The first T10, designated "T10-1" or "Blue 10", flew on 10 May 1977, with Sukhoi's chief test pilot, General Vladimir Ilyushin, at the controls.
Vladimir Ilyushin is the son of Sergei Ilyushin, who founded the Ilyushin OKB, but is a well-known and highly respected figure in his own right. The T10 was the 143rd aircraft he had piloted, including almost every Soviet type and even the B-25 Mitchell, the Cessna A-37, and the Northrop F-5E. Ilyushin was extremely pleased with the T10.
Blue 10 was immediately spotted by a US reconnaissance satellite, with NATO giving the new type the provisional name of "Ram-K", since Western intelligence did not know the name for the secret Zhukovsky flight center and simply referred to it as "Ramenskoye", a nearby town. Some overimaginative analysts thought it had variable geometry wings, and a few years would pass before that myth would be discarded.
Other analysts suggested that it was a copy of a Western aircraft, much to the irritation of the aircraft's designers. To be sure, the Ram-K had features similar to those of Western fighters that had preceded it, but those Western fighters in some cases had features of various Soviet fighters that had preceded them in turn. In reality, similar aerodynamic and mission requirements tended to lead to similar design solutions.
To an extent, however, the "copycat" accusation wasn't based completely on snobbery, since the USSR, particularly in Stalin's day, pragmatically did not hesitate to borrow, copy, or steal useful foreign technologies. In fact, the MiG and Sukhoi OKBs occasionally accused each other of copying as well, though similarities between their respective efforts were inevitable, as they were working from the same TsAGI aerodynamic recommendations.
The second T10 prototype, the "T10-2", was lost on 7 May 1978, with the pilot, Yevgeny Soloviev, killed while ejecting. A total of four prototypes were built by the Sukhoi OKB in the bureau's workshops, while five more were built at the state factory at Komsomolsk between 1980 and 1982. The state factory also provided subassemblies for the four prototypes developed at the Sukhoi workshops. As Western intelligence learned more about the aircraft, it was given the name of "Flanker-A".
The prototypes varied in detail, with two of those developed at the bureau workshops featuring production "AL-31" engines. Two more prototypes were under construction when the decision was made to redesign the aircraft, as tests showed the T10 prototypes were not meeting performance specifications. As the T10 stood, it was no match for the American F-15.
* The redesigned aircraft was designated the "T10S", with the "S" optimistically standing for "Series". Roughly ten T10S prototypes were produced, with some of them built new and some rebuilt from T10 prototypes. Initial T10S prototypes were similar to the T10, with incremental changes progressing through the series to the final production configuration.
The development effort continued to have more than its share of troubles. The first T10S prototype, the "T10S-1", rebuilt from the "T10-7", first flew on 20 April 1981 with Vladimir Ilyushin as pilot but was lost due to a fuel system problem, with Ilyushin ejecting safely.
The second prototype, the "T10S-2", rebuilt from the T10-12, broke up in flight on 23 December 1981, killing its pilot, Alexander Komarov. Another prototype, the "T10S-7", was wrecked when the pilot, Nikolai Sadovnikov, tried only too successfully to duplicate the fatal last flight of the T10S-2, but Sadovnikov managed to get the aircraft back down on the ground even though it had lost much of its left wing. It turned out that the two accidents were caused by defective leading-edge flaps that broke away. The flaps were promptly redesigned.
After these nasty teething problems were resolved, the test pilots were wildly enthusiastic about the performance and handling of the T10S, particularly in comparison to the T10. Unfortunately, after the flight problems of the aircraft were generally resolved, manufacturing problems remained. The production aircraft, designated "Su-27", only began to enter service in small numbers in 1986. NATO gave the production aircraft the designation "Flanker-B".
* While the manufacturing problems were being resolved, some of the prototypes were being used to set flight records. The "P-42" was converted from the T10S-3 by stripping it of all unnecessary equipment, and was used to successfully challenge records held by the similarly stripped-down F-15 "Streak Eagle". The flights were performed by Sukhoi test pilots Viktor Pugachev and Nikolai Sadovnikov. One of the flights set a record climb to 15,000 meters (49,200 feet) in 70.33 seconds, breaking the Streak Eagle's record by seven seconds.
This was cause for satisfaction, given the rocky path of the aircraft's development, and encouraged believers that the efforts would pay off after all. Another prototype, the "T10S-10", was stripped down and modified to challenge the 500 kilometer (270 nautical mile) closed circuit speed record, but it appears it was never actually used in such an attempt.
BACK_TO_TOP
[2] SU-27 INTO SERVICE
* The production Su-27 clearly retained much of the look of the original T10, but the changes were visible and obvious. The most apparent change was the adoption of a larger wing that featured straight edges, replacing the curved wing of the T10. Other visible changes included:
Moving the twin vertical tailplanes from positions directly atop the engines to just outboard of the engines.
Moving the nosewheel back behind the cockpit to reduce engine ingestion of debris during ground operations, and for the same reason installing inlet debris screens that retract and extend along with the landing gear.
Twin ventral fins.
A new "stinger" fuselage extension protruding backwards behind the engine exhaust.
A large airbrake behind the cockpit.
Of course, the production Su-27 had armament and operational avionics systems. Armament included:
A 30 millimeter Gryazev-Shipunov GSh-30-1 cannon firing from the top of the right LERX from just behind the cockpit, with typical rates of fire of 1,500 rounds per minute, ammunition storage of 149 rounds, and titanium skinning on the airframe around the gun muzzle.
Two stores pylons on each wing, plus wingtip rails for air-to-air missiles (AAMs).
Two centerline stores pylons in tandem between the engines.
A stores pylon on the outer corner of each engine nacelle.
In mature production aircraft, the wingtip rails could be removed and replaced with Sorbtsiya electronic countermeasures (ECM) pods, and some aircraft had three stores pylons on each wing, along with the wingtip rails.
An infrared track-&-search (IRST) sensor was fitted just in front of the cockpit along with a laser rangefinder, and the nose accommodated the "N-001" long-range radar system. In later production Su-27s, the tail stinger extension accommodated the tail radome for the "SPO-15 (L-006) Beryoza" radar homing and warning system (RHAWS), as well 32 three-shot chaff-flare dispensers. The stinger possibly also stored a jammer system.
The Su-27 was built mostly of light aluminum alloy, with some stainless steel and titanium. Flight controls were hydraulically operated, with some pneumatic backup systems. The nosewheel retracted forward, as did the main gear, rotating 90 degrees to lie flat in the wing roots. The pilot sat high with a good view in a Zvezda "K-36DM" zero-zero ejection seat. The ejection seat provided a "NAZ-8" survival pack, with rescue radio / beacon, rations, flares, medical supplies, and an inflatable raft.
The Su-27 was powered by twin Saturn-Lyulka AL-31F afterburning turbofans, with 12,515 kilograms (27,600 pounds) afterburning thrust each. The AL-31F was very reliable by Soviet engine standards, with a good time between overhaul of 1,000 hours, and the airframe allowed easy access to the engines.
SU-27 (LATE PRODUCTION):
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spec metric english
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wingspan 14.7 meters 48 feet 3 inches
length 21.9 meters 72 feet
height 5.93 meters 19 feet 6 inches
empty weight 16,380 kilograms 36,100 pounds
max loaded weight 28,300 kilograms 62,400 pounds
maximum speed 2,500 KPH 1,550 MPH / 1,350 KT
service ceiling 18,000 meters 59,000 feet
combat radius 1,500 kilometers 930 MI / 810 NMI
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* Su-27s began to perform mock intercepts of Western aircraft over the Barents Sea in early 1987, though at first they kept their distance. However, Norwegian F-16 pilots soon managed to get pictures of the type, and in September 1987 the crew of a Norwegian P-3 Orion ocean-patrol aircraft got a much closer view than they liked when an Su-27 clumsily clipped one of the P-3's propellers with its tail. Fortunately, both aircraft made it safely back home.
The Su-27 made its formal introduction to the West at the 1989 Paris Air Show, when Viktor Pugachev ran the aircraft through the now-famous "Cobra" maneuver, lifting the fighter to an angle of attack of over 90 degrees to its line of flight, causing abrupt deceleration until it nosed back down. The Cobra maneuver was apparently invented by another Sukhoi test pilot, Valerii Menitsky, as a flight-test exercise, but it became associated with Pugachev, it seems with his encouragement, and is also often called the "Pugachev maneuver" or "Pugachev Cobra". Few aviation experts believe that the Cobra maneuver has much combat utility, but it is undeniably a spectacular airshow trick.
It still shocked Western observers, since there were few or no Western aircraft that could perform the Cobra maneuver, and even though it may have been nothing more than a stunt, it demonstrated that the Su-27 was remarkably agile and very strongly built. However, observers noted that an Su-27 fully loaded for combat operations would not have anywhere near such capabilities, and is likely not all that capable as a close-in dogfighter, unsurprising for a big aircraft designed as a long-range interceptor.
The Su-27's agility is still impressive given its size, all the more so because the Su-27 is not a "dynamically unstable" design. Western designers have chosen to build maneuverable aircraft by designing them to be aerodynamically unstable, and then using advanced control systems to keep them in the air. Russian designers, preferring reliability and with less access to sophisticated avionics systems, opted for building a stable design and tweaking it for maximum maneuverability.
The Su-27 was, as mentioned, originally developed as a long-range "fighter interceptor" for the VVS and the Soviet air defense command (PVO), and was largely optimized for this role. Typical air-defense warload could be six "beyond visual range (BVR)" missiles and two or four short-range "dogfighting" missiles. While the Su-27's standard BVR missile, the "R-27" or "AA-10 Alamo" in its NATO codename, is regarded as inferior to the US AIM-120 AMRAAM, the standard dogfighting missile, the "Vympel R-73 / AA-11 Archer", is regarded one of the best in its class.
The R-73 has an "off-boresight" engagement capability, with the pilot cueing it to a target not directly in front of the aircraft with a helmet-mounted sight. The helmet-mounted sight can also be used to cue the IRST and laser rangefinder. While the US was developing AMRAAM at great expense and difficulty, the Soviets moved ahead with the R-73, and now the Americans are trying to catch up with the "AIM-9X Sidewinder" AAM.
The Su-27's electronics systems are less sophisticated than those of equivalent Western aircraft, and there are questions about their reliability, but the IRST has good tracking capability and the radar has excellent range, However, the radar does not have processing sophistication of Western counterparts. In the air-defense role, the Su-27 is designed to operate in conjunction with ground or air-based air-defense networks, a traditional Soviet practice, and the Su-27 has a datalink to allow it to perform intercepts "passively", without using its own radar.
Although the reliability of the Su-27's electronics may be uncertain, Russian partisans like to mock Western aircraft for their delicate mechanical nature and inability to operate off of rough airstrips. The rugged Su-27 was designed for such an environment and has no difficulty with it.
The large size of the Su-27 makes it useful as a strike aircraft, able to carry a wide range of munitions, but strike is a secondary mission for the basic Su-27. A reasonable judgement of the Su-27 would place it as superlative in its role as a fighter-interceptor, but probably not the equal of the F-15 as a multirole aircraft.
* By the way, the Su-27 has no formal name. Sukhoi says the aircraft is referred to as the "Azure Lighting", but it appears that it is generally called the "Crane", for its bent-necked appearance in flight. Some sources claim that Russian personnel occasionally even refer to it by its NATO codename, "Flanker".
BACK_TO_TOP
[3] TWO-SEAT SU-27UB / EXPORT SU-27SK / NAVAL SU-27K
* The Su-27 is a big and complicated aircraft that demands much of its pilots, and so during T10 and T10S development the Sukhoi OKB also worked on a two-seat operational trainer version. Due to the development difficulties discussed earlier, work on the two-seat version had to be set aside until the single-seat version was in production, and the first two-seat T10U prototype did not fly until March 1985, entering production and service as the Sukhoi "Su-27UB" a year or two later. While initial prototypes were built in Sukhoi OKB facilities in Moscow and Komsomolsk, full production was transferred to a state factory in Irkutsk.
The Su-27UB has a tandem seats under a single canopy, with the back seat stepped up above the front seat, providing the flight instructor in the back seat a good view of both the world in front of the aircraft and of what the trainee in the front seat is doing. Sukhoi engineers like to point out that the view from the rear seat is much superior to that from the rear of two-seat F-15s. This arrangement gives the Su-27UB an even more "crane-necked" appearance than the Su-27.
The second seat was accommodated by stretching the fuselage, and the vertical tailfins were increased in height slightly to compensate for the changed aerodynamics. The Su-27UB was designed to be fully combat capable. Addition of the second seat increased the weight of the aircraft by only about 1,120 kilograms (2,470 pounds) without reduction in fuel capacity, and aside from minor increases in runway requirement and comparably minor decreases in top speed, the Su-27UB's performance is very similar to that of the single-seat Su-27. Like the single-seat Su-27, early production Su-27UBs lack certain systems and features of late-production aircraft.
* The late-production single-seat Su-27 was used as the basis for the export variant, the "Su-27SK" (where "SK" stands for "Series Kommercial"). While the Su-27SK is externally all but identical to the Su-27, it has a downgraded system fit. A two-seat "Su-27UBK" was also built for the export market.
The Chinese were the first export customer for the Su-27, signing a contract in 1991 for 24 Su-27SKs and 2 Su-27UBKs, with initial deliveries in 1992. The Chinese bought another batch of exactly the same number and types of aircraft in 1995, and in 1996 the Chinese signed a license agreement to allow them to produce up to 200 Su-27s of their own. The license agreement apparently stipulates that they cannot export the type, which has the Chinese designation of "J-11".
In 1999, the Chinese ordered 40 "Su-30MKK" multirole combat aircraft, which feature a new radar and fire-control system. The Su-30 variants are discussed in more detail later. Initial delivery of a batch of ten took place in December 2000.
In the mid-1990s, Vietnam, not to be outdone by their ancient Chinese rival, also bought a number of Su-27s. Syria, Algeria, Iran, and Libya have expressed various levels of interest in obtaining the type as well. Of course, a number of Su-27s were "inherited" by some of the newly independent states, such as Belarus and Kazakhstan, created by the collapse of the USSR, but these were not export variants.
* The Soviet Navy had planned to acquire four fleet aircraft carriers, and so accordingly planned to build navalized versions of the MiG-29 and Su-27 for carrier operations.
Work on a navalized Su-27 actually went back almost to the very beginning of the design of the Su-27 family. T10S prototypes were modified to test features of navalized variants in an incremental fashion. The first test flights, from a dummy land-based carrier deck at Saki in the Crimea, featured aircraft fitted with with small canard wings for better low-speed approach, improved short takeoff performance, and enhanced combat maneuverability. Tests then went on to aircraft fitted with arresting gear, and then to tests of aircraft with carrier landing systems.
The carriers were to be fitted with "ski-jump" takeoff ramps, rather than catapults, and one of these navalized Su-27 prototypes made an initial takeoff from a land-based ski jump in August 1982. In operational practice, the aircraft was to take off a carrier deck by building up full thrust against a tilt-up blast deflector panel until the aircraft sheared restraints holding it down to the deck. The fighter would then accelerate up the deck and be tossed into the air with the ski-jump.
This unusual scheme was devised because the Soviets had no experience in building aircraft carrier catapults, and didn't want to delay introduction of the carriers while puzzling around with a new and demanding technology.
These modified prototypes led to specific prototypes for the navalized aircraft, designated "T10K". These aircraft had canards, an arresting hook, and carrier landing systems, as well as a retractable inflight refueling probe to allow the aircraft to take off with a reduced fuel load and top off in flight. However, they did not have the ruggedized landing gear required for carrier landings, and lacked folding wings. Pugachev flew the first T10K in August 1987, though that particular aircraft was lost in a mishap in 1988.
The production navalized "Su-27K" featured the required heavier landing gear and folding wings, with drooping outer ailerons and inner double-slotted flaps for low-speed carrier approaches. It began carrier trials on board the carrier TBILSI in November 1989, again with Pugachev at the controls, leading to introduction to formal carrier operations in September 1991.
A batch of 18 Su-27Ks were built in 1982 and 1983, though abandonment of plans for the four-carrier force in the aftermath of the collapse of the USSR meant that the need for building more Su-27Ks vanished. The KUZNETZOV, as the TBILISI had been renamed after the end of the Soviet Union, made a cruise in the Mediterranean in 1996, giving the Su-27K its first taste of ocean operations. NATO assigned the Su-27K the codename "Flanker-D", while the Sukhoi OKB calls the aircraft the "Su-33".