Su-25 "Rook" or "Flying Tank"
The first experience of modern civil war is, of course, accumulated in Afghanistan. And he immediately showed a lack of effectiveness aviation. In addition to the unpreparedness of the pilots and the flaws in tactics, the aircraft themselves were poorly matched with the nature of the counterguerrilla war. The supersonic fighter-bomber designed for the European theater of war turned out to not turn around in the mountain gorges, and their sophisticated aiming and navigation equipment was practically useless when searching for an inconspicuous enemy. The capabilities of the aircraft remained unclaimed, and the effectiveness of their attacks was low.
The Su-25 attack aircraft turned out to be a suitable vehicle - maneuverable, obedient to drive, well armed and protected. Su-25 (by NATO codification: Frogfoot) - Soviet-Russian armored subsonic attack aircraft. Designed for direct support of ground forces over the battlefield day and night with visual visibility of the target, as well as the destruction of objects with given coordinates around the clock in any weather conditions. In the Russian troops got the nickname "Rook".
«2» History create
At the end of 60. it became clear that the Su-7B, MiG-19, MiG-21 and Yak-28 aircraft do not effectively defeat small ground targets on the battlefield, and the lack of reservation of the crew cabin and important units makes them vulnerable to small arms weapons and small-caliber artillery.
In March, 1968, the senior teacher of the Air Force Academy. NOT. Zhukovsky, I.Savchenko, suggested that the POO Sukhoi Design Bureau specialists jointly develop a project for a new ground support aircraft. The initiative group (O.S. Samoilovich, D.N.Gorbachev, V.M. Lebedev, Yu.V. Ivashechkin and A.Monakhov) developed the battlefield aircraft (SPB) and after determining its general appearance, presented the project P.O. Sukhoi, who approved it under the name T-8. In March, 1969 was held a competition for the development of a prototype attack aircraft with the participation of KB. A.I. Mikoyan and A.S. Yakovlev (proposed projects to modify the MiG-21 and Yak-28), S.V. Ilyushin and P.O. Sukhoi (new projects IL-102 and T-8). The winner was the T-8 project, which had a more sophisticated aiming complex and smaller, compared to the IL-102, dimensions and weight. The project envisaged the development of an easy-to-manufacture and unpretentious attack aircraft designed to be operated by a minimally prepared flight and ground crew, with little time to prepare for departure using the ground-based airmobile complex, which provided an autonomous ground attack aircraft on restrictedly equipped ground airfields.
The elaboration of the preliminary design of the aircraft directly supporting the troops over the battlefield of the SPB (“Polly Boy’s Aircraft”) was initiated by the instructor of the Air Force Academy named after Yu.A.A.Gagarin, I.V. Savchenko and the staff of the OKO Design Bureau P.O. Sukhoi, O. S.Samoylovich, D.N.Gorbachev, V.M. Lebedev, Yu.V. Ivashechkin and A.Monakhov in March 1968. In May 1968, the aircraft design was started in the PO O. Sukhoi Design Bureau under the name T-8 . The study of the aerodynamic scheme of the future attack aircraft started at TsAGI in 1968, the USSR Ministry of Defense, at the suggestion of Defense Minister A.A. Grechko, in March 1969 announced a competition for a light attack aircraft project in which the Sukhoi Design Bureau (T-8), Yakovlev (Yak -25LSH), Mikoyan and Gurevich (MiG-21LSH) and Ilyushin (IL-42). For the competition were formulated Air Force requirements. The competition was won by T-8 and MiG-21ЛШ aircraft. Production of working drawings and preparation for the construction of a prototype aircraft - summer 1970 g. At the same time, the Air Force changed the requirements for maximum ground speed to 1200 km / h, which put the project at risk of complete processing. By the end of 1971, it was possible to reconcile changes in the requirements for maximum speed to 1000 km / h (0.82 M).
The design of the T-8 was resumed in January 1972 after P.O. Sukhoi approved the general view of the attack aircraft (06.01.1972) and signed an order to begin the working design of the aircraft. MP Simonov was appointed project manager, Yu.V. Ivashechkin was appointed lead designer. Since August, 1972, the chief designer of T-8, is OS Samoylovich, the lead designer with 25.12.1972, is Yu.V. Ivashechkin (he is also the chief designer with October 6, 1974). The model of the aircraft was adopted by the commission in September and the construction of the prototype began at the end of 1972. The first flight of the prototype T-8-1 was made at the LII airfield in Zhukovsky 22 in February 1975 (pilot - V.S. Ilyushin). The second prototype, with some design changes (T-8-2), was put to the test in December 1975.
In the summer of 1976, on prototypes, engines were replaced with more powerful R-95Sh, some design elements were changed (1978) - the updated prototypes were named T-8-1D and T-8-2Д. In July, the X-NUMX T-1976 was called the “Su-8” and preparations began for mass production at the aircraft plant in Tbilisi (initially it was planned to start production in Poland). Tactical and technical requirements for the Su-25 attack aircraft with the P-25Sh engine, modified avionics composition - T-95-8D - approved by the USSR Ministry of Defense only 1 March 9 and discussed with 1977 on 11 May 24 on the mockup .
Information about the aircraft and the code name RAM-J appeared in the West in 1977, according to space reconnaissance data (RAM = Ramenskoye (airfield), railway station near the aerodrome of LII). The first production vehicle (T-8-3) was released in Tbilisi in 1978 and made the first flight of 18 on June 1979 (pilot - Yu.A. Egorov). State tests of the aircraft took place (first stage) from March to 30 in May 1980 (completed in December 1980). The production of double Su-XNUMHUB / UT / UTG and single Su-25 was conducted at the aircraft plant in Ulan-Ude. In March, 39 was signed an act of completion of state tests of the aircraft and it is recommended for adoption by the USSR Air Force. In April, the 1981, the aircraft began to arrive in the line units. Since June, 1981 Su-1981 participated in the hostilities in Afghanistan. Officially, the Su-25 was adopted in 25.
6.01.1972, the general view of the T-8 attack aircraft was approved and detailed design started under the guidance of MP Simonov (from August - OS Samoylovich), and from 25.12.1972 - Yu.V. Ivashechkin, who from 6.10.1974 became the head of the topic. In May, 1974 was decided to build two copies of the T-8 aircraft, in December, an experienced attack aircraft was transported to the LII airfield, and on February 22 1975, under the control of V.S. Ilyushin, took off. In June, 1976 was decided to deploy the production of attack aircraft at an aircraft factory in Tbilisi. In March, the tactical and technical requirements for the aircraft were approved by 1977, and the design bureau presented to the customer a draft design of an aircraft with P-95Sh engines, a modified wing and a more advanced aiming and navigation complex.
Officially, the aircraft was handed over to state testing in June 1978, the first flight was made on July 21, and flights under the state testing program began in September (V.Ilyushin, Yu.Egorov). By the beginning of the state tests of the aircraft, the Su-17МЗ refined aim-navigation system was installed, which ensured the use of the most modern guided weapons, including missiles with a laser guidance system. The cannon container was replaced by a double-barreled 30-mm cannon AO-17A (GSH-2-30 series). The pre-production prototype of the first Tbilisi assembly, on which all conceptual solutions of the attack aircraft project were implemented, took off 18 June 1979.
In the winter of 1979-1980. on the T-8-1D, T-8-3 and T-8-4 aircraft, the first state tests were completed. After the successful use of the T-1980-8D and T-1-8 planes in Afghanistan in April-June, the Air Force leadership decided to read this as the second stage of the state test without flight studies of the spin characteristics. The final flights of the test program took place at the Mary airfield in Central Asia, 3 was officially completed, and in March 30.12.1980 was signed a certificate of their termination with the recommendation to put the aircraft into operation. In connection with the failure of some points of the TTZ attack aircraft Su-1981 was adopted in 25.
"3" Aerodynamic design
In terms of its aerodynamic layout, the Su-25 attack aircraft is a plane made according to the normal aerodynamic configuration, with a high wing.
The aerodynamic layout of the aircraft is tuned to obtain optimal performance at subsonic flight speeds.
The wing of the aircraft has a trapezoidal shape in plan, with a sweep angle on the leading edge of 20 degrees, with a constant relative thickness of the profile along the wing span. The wing of the aircraft has a planned projection area 30, 1 m. Square. The angle of the transverse wing V is - 2, 5 degrees.
The selected laws on the swing span and curvature of the profile ensured a favorable development of flow disruption at high angles of attack, which begins near the rear edge of the wing in its middle part, which leads to a significant increase in the moment of a dive and naturally prevents the aircraft from getting into supercritical angles of attack.
The load on the wing is selected from the conditions for ensuring the flight to the ground in a turbulent atmosphere at speeds up to the maximum flight speed.
Since, on the basis of the flight conditions in a turbulent atmosphere, the load on the wing is high enough, then to ensure a high level of take-off and maneuvering characteristics, effective wing mechanization is necessary. For these purposes, the aircraft implemented wing mechanization consisting of retractable slats and two-slot three-section (maneuver-take-landing) flaps.
The increment of the moment from the released wing mechanization, is countered by the rearrangement of the horizontal tail.
Installation at the ends of the wing containers (gondolas), in the tail parts of which are fissile plates, allowed to increase the maximum aerodynamic quality. To do this, the cross-sectional shape of the containers and their installation position relative to the wing have been optimized. The longitudinal sections of the containers are an aerodynamic profile, and the cross sections are oval with compacted upper and lower surfaces. Tests in wind tunnels confirmed the calculations of aerodynamics to obtain when installing containers higher values of maximum aerodynamic quality.
The brake pads installed in the wing containers meet all standard requirements for them - an increase in the resistance of the aircraft no less than twice, and their release does not lead to the rebalancing of the aircraft and the reduction of its load-bearing properties. The brake plates are made fissile, which increased their efficiency by 60%.
The aircraft has a fuselage with lateral unregulated air inlets with an oblique entrance. Lantern with a flat Lobovyk smoothly into the gargrot located on the upper surface of the fuselage. Gargrot in the rear fuselage merges with the tail boom that separates the engine nacelles. The tail boom is a platform for installation of horizontal tail with a rudder and single-fin vertical tail with a rudder. The tail beam ends container parachute brake installation (PTU).
The aerodynamic layout of the Su-25 attack aircraft provides:
1. obtaining high aerodynamic quality in cruising flight and high lift coefficients in takeoff and landing modes, as well as in maneuvering;
2. favorable course of the dependence of the longitudinal moment on the angle of attack, which prevents reaching large supercritical angles of attack and, thereby, increases flight safety;
3. high maneuverability when attacking ground targets;
4. acceptable characteristics of longitudinal stability and controllability in all flight modes;
5. Steady dive mode with an angle of 30 degrees at a speed of 700 km/h.
The high level of aerodynamic quality and bearing properties made it possible to return the aircraft with large damage to the airfield.
The aircraft fuselage has an ellipsoid section, made according to the semi-monocoque scheme. The design of the fuselage is assembled-riveted, with a frame consisting of a longitudinal power set - spars, beams, stringers and transverse power set - frames.
Technologically, the fuselage is divided into the following main parts:
1. head part of the fuselage with a folding toe, a folding part of the canopy, wings of the nose landing gear;
2. the middle part of the fuselage with the wings of the main landing gear (air intakes and wing consoles are attached to the middle part of the fuselage);
3. the tail section of the fuselage, to which the vertical and horizontal tail are attached.
Container brake parachute is the ending of the rear fuselage. The fuselage of the aircraft has no operational connectors.
Su-25 attack aircraft is a fairly highly protected aircraft. The combat survivability systems of the vehicle account for 7,2% of its normal take-off weight, which is as much as 1050 kg. At the same time, vital aircraft systems are shielded by less important systems and duplicated. Particular attention was paid to the development of the protection of critical elements and components of the aircraft - the cockpit and the fuel system. The cockpit is made welded from special aviation titanium armor ABVT-20. The thickness of the armor plates with which the pilot is protected ranges from 10 to 24 mm. Front cockpit glazing provides the pilot with anti-bullet protection and is a special glass block TSK-137 with a thickness of 65 mm. Behind the pilot, the pilot is protected by a steel armorplate with a thickness of 10 mm and an armored headpiece with a thickness of 6 mm. The pilot is almost completely protected from firing from any small arms with a caliber up to 12,7 mm in the most dangerous areas from a barrel weapon with a caliber up to 30 mm.
The rescue of the pilot in the event of a critical attack of the attack aircraft is carried out using the K-36L ejection seat. This seat provides the rescue of the pilot at all speeds, modes and altitudes of flight. Immediately before the ejection, the cockpit canopy is reset. The ejection from the aircraft is done manually using 2's control handles, for which the pilot must be pulled with both hands.
"4" power plant
The aircraft has two interchangeable formless turbojet engines P-95, with an unregulated nozzle with a downstream drive box, with autonomous electric starting.
The P-95 is a twin-shaft, single-circuit turbojet aircraft engine, developed in 1979 at the FSUE "Scientific-Production Enterprise" Motor "" under the direction of S. A. Gavrilova,
Key Features:
• Overall dimensions, mm:
• length - 2700
• maximum diameter (without aggregates) - 772
• max. height (without object aggregates) - 1008
• max. width (without object aggregates) - 778
• Dry weight, kg. - 830
Parameters in terrestrial conditions at maximum mode:
• thrust, kgf - 4100
• air consumption, kg/s - 67
• specific fuel consumption, kg/kgf.h - 0,86
The engines are located in the engine compartments on both sides of the tail boom of the aircraft.
Air is supplied to the engines through two cylindrical air channels with oval subsonic unregulated air inlets.
The aircraft engine has an unregulated tapering nozzle located in the tail section of the engine nacelle so that its cut coincides with the engine nacelle cut. Between the outer surface of the nozzle and the inner surface of the engine nacelle there is an annular gap for air to escape through the engine compartment.
The systems that ensure the operation of the power plant of the aircraft include:
• fuel system;
• engine control system;
• engine control devices;
• engine start system;
• engine cooling system;
• fire protection system;
• drainage and breather system.
To ensure the normal operation of the engines and its systems, the drainage system ensures the removal of fuel, oil and slurry overboard after the engines stop or in the event of a failed launch.
The engine management system is designed to change the operating modes of the engines and provides autonomous control of each engine. The system consists of an engine control panel on the left side of the pilot's cabin and cable wiring with rollers that support the cable, tandems regulating the tension of the cables, and gear units in front of the engines.
The engine oil system is of a closed type, autonomous, designed to maintain the normal temperature state of moving parts, reduce wear and reduce friction losses.
The starting system provides autonomous and automatic starting of engines and their output at a steady speed. Starting engines on the ground can be made from the onboard battery or from the airfield power source.
Cooling of engines, assemblies and fuselage design from overheating is provided by the oncoming air flow through cooling air intakes due to high-speed pressure. Air intakes for cooling the engine compartments are located on the upper surface of the engine nacelles. The air which got to them under the influence of a high-speed pressure spreads on engine compartments, cooling the engine, its units and designs. The exhaust cooling air exits through the annular gap formed by the nacelle and engine nozzles.
Electric generators installed on the engines are also cooled by an oncoming air flow due to the velocity head. The air intakes for cooling the generators are installed on the upper surface of the tail boom of the fuselage in front of the keel, in the tail boom the nozzles are divided into left and right pipelines. Having passed the generators and cooled them, the air goes into the engine compartment, mixing with the main cooling air.
"5" Specifications:
Crew: 1 pilot
Length: 15,36 m (with LDPE)
Wingspan: 14,36 m
Height: 4,8 m
Wing area: 30,1 m²
Weight:
- empty: 9 315 kg
- equipped: 11 600 kg
- normal take-off weight: 14 600 kg
- maximum take-off weight: 17 600 kg
- mass armor protection: 595 kg
Powerplant: 2 × TRD R-95Sh
Flight characteristics:
Speed:
- maximum: 950 km / h (with normal. combat load)
- cruising: 750 km / h
- Landing: 210 km / h
Combat radius: 300 km
Practical range at height:
- without PTB: 640 km
- with 4 × PTB-800: 1 250 km
Practical range at the ground:
- without PTB: 495 km
- with 4 × PTB-800: 750 km
Ferrying range: 1 950 km
Ceiling: 7 000 m
Maximum combat use height: 5 000 m
Armament:
One 30-mm double-barreled gun GSH-30-2 in the lower nose with 250 cartridges. Combat load - 4340 kg on 8 (10) suspension units
Normal load - 1340 kg.
"6" Purpose of the aircraft
Su-25 - attack aircraft. The main purpose of attack aircraft is the direct air support of ground forces on the battlefield and in the tactical depth of enemy defenses. The planes were supposed to destroy the tanks, artillery, mortars, other technical means, as well as the enemy's manpower; to oppose the approach to the battlefield of tactical and operational reserves of the enemy, destroy headquarters, communications equipment and field depots, disrupt transportation, destroy planes at airfields and actively fight air transport and bomber aircraft; to sink river and sea vessels, to conduct aerial reconnaissance.
"7" Combat use
The Su-25 used in Afghanistan war (1979-1989), Iran-Iraq war (1980-1988), Abkhaz war (1992-1993), Karabakh war (1991-1994), first and second Chechen wars (1994-1996 and 1999 — 2000), the War in South Ossetia (2008), the War in Ukraine (2014).
The first Su-25 began to arrive in the line units in April 1981 of the year, and since June - serial attack aircraft have been actively working on enemy targets in Afghanistan. The advantage of the new attack aircraft was obvious. Operating at lower speed and altitude, the Su-25 did work that other aircraft could not do. Another proof of the effective operation of the Su-25 is the fact that combat missions often took place with a bomb load exceeding 4000 kg. This plane became a truly unique machine, thanks to which hundreds, and possibly thousands of Soviet soldiers were saved.
In Afghanistan (1979-1989gg.) For 8 years, starting in April 1981, Su-25 has confirmed high combat effectiveness and survivability. According to the OKB. P.O. Sukhoi made about 60 thousand combat missions, launched 139 guided missiles, of which 137 hit targets, and a huge number of unguided missiles were launched. Losses amounted to 23 aircraft, with an average flight time for each of them 2800 hours. Downed Su-25 had, on average, 80-90 combat damage, there were cases of the return of the aircraft to the base with 150 holes. According to this indicator, it significantly surpassed other Soviet planes used in Afghanistan and American planes of the Vietnam War. Over the entire period of hostilities, there were no cases of fuel tanks exploding and loss of attack aircraft due to the death of the pilot.
However, the present baptism in modern history within the Russian borders took Su-25 during the first Chechen campaign, when it was necessary to work not only in mountain conditions, but also in terms of settlements. There were cases when using a precision-guided laser-guided weapon, the Su-25 was working on a target within the limits of a single taken area at a household. Also, a pair of attack aircraft distinguished themselves in the liquidation of the CRI leader Dzhokhar Dudayev, who were guided onto the target by the radar reconnaissance A-50. In consequence, it was in the Caucasus that the effectiveness of the Su-25 and its modification was often the key to successful completion of the task and the loss of the land group without loss.
It is also worth noting that, despite its venerable age, the Su-25 successfully worked during the recent "Ossetian-Georgian" conflict, when Russian pilots successfully coped with the ground targets of the enemy and only three out of ten boards were shot down from the Buk air defense system. , which Georgia provided Ukraine. It was during this period in the network appeared a photo of one of the sides of the Su-25, which flew to the airbase with a torn right engine. Flew, and without any problems, on one engine.
8 Manufacturing and Modifications
Su-25 was serially produced from 1977 of the year to 1991 of the year. Existed and there is a huge number of modifications of the legendary aircraft.
With the 1986 of the year, the production of the Sparky Su-25UB, a combat training two-seater aircraft, began at the plant in Ulan-Ude. Apart from adding the second pilot seat, the aircraft is almost completely identical to the classic attack aircraft and can be used both for training and for combat operations.
The most modern modification of the Su-25SM serial attack aircraft differs from the “original source” with a more modern complex of onboard electronic equipment and the presence of more modern weapons.
The project of the carrier-based attack aircraft with a catapult take-off Su-25K did not go beyond the project stage (due to the lack of Russian aircraft carriers with catapults), but several deck-based training aircraft Su-25UTG designed to be based on the Admiral aircraft cruiser were released fleet Kuznetsov ”with a springboard take-off. The plane turned out to be so successful that it serves as the main training aircraft for training pilots on deck aviation.
The most interesting and complex modification is the Su-25T anti-tank aircraft, the decision to create which was made back in the 1975 year. The main problem in the development of this aircraft was the creation of airborne electronic equipment (avionics) for detecting, tracking and pointing missiles at armored targets. The basis of the aircraft was taken glider double training aircraft Su-25UB, all the space reserved for the co-pilot, took a new avionics. It was also necessary to move the cannon into the cabin compartment, to expand and extend the nose, where the Squall daytime optical sighting system was located to control the firing of the Whirlwind supersonic missiles. Despite the significant increase in internal volume, there was no room for a thermal imaging system in the new machine. Therefore, the night vision system “Mercury” was mounted in the outboard container under the fuselage at the sixth point of the suspension.
"9" The future of the Su-25
In terms of replacement, currently worthy alternatives to the Su-25 is not yet represented. The assault aircraft niche is so unique that it is difficult to create something more suitable for it than this attack aircraft. The Ministry of Defense said that, of course, projects that are preparing to replace the Su-25, exist, but their use is still premature. "The possibilities of attack aircraft in Russia have not yet been exhausted," - said the Ministry of Defense. “At the moment there is no need to immediately replace the Su-25 with another type of lethal apparatus. The advantage will be achieved through a deep modernization of the Su-25, both in terms of retrofitting the aircraft itself, and in terms of the weapons used in it. In particular, technologies that operate on the principle of “shot-and-forget” will be introduced.
Creating the Su-25, the designers saw in advance in it a huge potential for modernization. Unique in its survivability of the aircraft, today is the main fighting machine of direct support for the troops.
The main attack aircraft of the Russian air force Su-25 will be upgraded in the near future. It is planned to retool all available aircraft of this type in accordance with the modification of the Su-25CM. In addition to finalizing all attack aircraft will be overhauled, which will extend their life by 15-20 years.
Primary Sources:
https://ru.wikipedia.org/wiki/%D1%F3-25
http://www.airwar.ru/enc/attack/su25.html
http://worldweapon.ru/sam/su25.php
http://www.zelezki.ru/aviacatalog/russia/3193-shturmovik_su-25.html
http://kollektsiya.ru/samoleti/121-s...hturmovik.html
Information