Sukhoi Su - 25 The Sukhoi Su - 25 ( NATO reporting name : " Frogfoot " ) is a single - seat , twin - engine jet aircraft developed in the Soviet Union by the Sukhoi Design Bureau . It was designed to provide close air support for the Soviet Ground Forces . The first prototype made its maiden flight on 22 February 1975 . After testing , the aircraft went into series production in 1978 at Tbilisi in the Soviet Republic of Georgia . Russian air and ground forces nicknamed it " " Grach " " ( " Rook " ) . Early variants included the Su - 25UB two - seat trainer , the Su - 25BM for target - towing , and the Su - 25K for export customers . Some aircraft are being upgraded to version Su - 25SM as of 2012 . The Su - 25T and the Su - 25TM ( also known as Su - 39 ) were further developments , not produced in numbers . The Su - 25 , along with the Su - 34 , were the only armoured fixed - wing aircraft in production in 2007 . Su - 25 is in service with Russia , other CIS states , and export customers . The Su - 25 has seen combat in several conflicts during its more than 25 years in service . It was heavily involved in the Soviet war in Afghanistan , flying counter - insurgency missions against the Mujahideen . The Iraqi Air Force employed Su - 25s against Iran during the 1980 – 89 Iran – Iraq War . Most were later destroyed or fled to Iran in the 1991 Persian Gulf War . Abkhazian separatist s used Su - 25s in 1993 against Georgians during the Abkhazian War . The Macedonian Air Force used Su - 25s against Albanian insurgents in the 2001 Macedonia conflict and , in 2008 , Georgia and Russia both used Su - 25s in the Russo - Georgian War . African states , including the Ivory Coast , Chad , and Sudan have used the Su - 25 in local insurgencies and civil wars . Development . In early 1968 , the Soviet Ministry of Defence decided to develop a specialised " shturmovik " armoured assault aircraft in order to provide close air support for the Soviet Ground Forces . The idea of creating a ground - support aircraft came about after analysing the experience of ground - attack ( " shturmovaya " ) aviation during the 1940s , 1950s , and 1960s . The Soviet fighter - bombers in service or under development at this time ( Su - 7 , Su - 17 , MiG - 21 and MiG - 23 ) did not meet the requirements for close air support of the army . They lacked essential armour plating to protect the pilot and vital equipment from ground fire and missile hits , and their high flight speeds made it difficult for the pilot to maintain visual contact with a target . Having taken into account these problems , Pavel Sukhoi and a group of leading specialists in the Sukhoi Design Bureau started preliminary design work in a comparatively short period of time , with the assistance of leading institutes of the Ministry of the Aviation Industry and the Ministry of Defence . In March 1969 , a competition was announced by the Soviet Air Force that called for designs for a new battlefield close - support aircraft . Participants in the competition were the Sukhoi Design Bureau and the Design Bureaus of Yakovlev , Ilyushin and Mikoyan . Sukhoi finalised its " T - 8 " design in late 1968 , and began in work on the first two prototypes ( T8 - 1 and T8 - 2 ) in January 1972 . The T8 - 1 , the first airframe to be assembled , was completed just before a major national holiday on 9 May 1974 . However , it did not make its first flight until 22 February 1975 , after a long series of test flights by Vladimir Ilyushin . The Su - 25 surpassed its main competitor in the Soviet Air Force competition , the Ilyushin Il - 102 , and series production was announced by the Ministry of Defence . During flight - testing phases of the T8 - 1 and T8 - 2 prototypes ' development , the Sukhoi Design Bureau ' s management proposed that the series production of the Su - 25 should start at Factory No . 31 in Tbilisi , Soviet Republic of Georgia , which at that time was the major manufacturing base for the MiG - 21 UM " Mongol - B " trainer . After negotiations and completion of all stages of the state trials , the Soviet Ministry of Aircraft Production authorised manufacture of the Su - 25 at Tbilisi , allowing series production to start in 1978 . In the late 1980s and early 1990s , several Su - 25 variants appeared , including modernised versions , and variants for specialised roles . The most significant designs were the Su - 25UB dual - seat trainer , the Su - 25BM target - towing variant , and the Su - 25T for antitank missions . In addition , an Su - 25KM prototype was developed by Georgia in co - operation with Israeli company Elbit Systems in 2001 , but so far this variant has not achieved much commercial success . The Su - 25 is the only armoured aircraft still in production in 2007 . The Russian Air Force , which operates the largest number of Su - 25s , had planned to upgrade older aircraft to the Su - 25SM variant , but funding shortfalls have slowed the progress ; by early 2007 only seven aircraft had been modified . Design . Overview . The Su - 25 has a normal aerodynamic layout with a shoulder - mounted trapezoidal wing and a conventional tailplane and rudder . Several different metals in differing amounts are used in the construction of the airframe : 60 % aluminium , 19 % steel , 13 . 5 % titanium , 2 % magnesium alloy , and 5 . 5 % other materials . All versions of the Su - 25 have a metal cantilever wing , of moderate sweep and high aspect ratio , and equipped with high - lift devices . The wing consists of two cantilever sections attached to a central torsion box , forming a single unit with the fuselage . The air brakes are housed in separate fairings at the tip of each wing . Each wing has five hardpoints for weapons carriage , with the attachment points mounted on load - bearing ribs and spars . Each wing also features a five - section leading edge slat , a two - section flap , and an aileron . The flaps are mounted by steel sliders and rollers , attached to brackets on the rear spar . The trapezoidal ailerons are located near the wingtips . The fuselage of the Su - 25 has an ellipsoidal section and is of semi - monocoque , stressed - skin construction , arranged as a longitudinal load - bearing framework of longerons , beams and stringers , with a transverse load - bearing assembly of frames . The one - piece horizontal tailplane is attached to the load - bearing frame at two mounting points . Early versions of the Su - 25 were equipped with two R95Sh non - afterburning turbojets , in separate compartments on either side of the rear fuselage . The engines , sub - assemblies , and surrounding fuselage structure are cooled by air provided by the cold air intake s located on top of the engine ' s nacelles . A drainage system collects oil , hydraulic fluid residues , and fuel from the engines after flight or after an unsuccessful start . The engine control systems allows independent operation of each engine . The latest versions ( Su - 25T and TM ) are equipped with improved R - 195 engines . The cannon is located in a compartment beneath the cockpit , mounted on a load - bearing beam attached to the cockpit floor and the forward fuselage support structure . The nose is fitted with distinctive twin pitot probes and hinges up for service access . Cockpit . The pilot flies the aircraft by means of a centre stick and left hand throttle s . The pilot sits on a Zvezda K - 36 ejection seat ( similar to the Sukhoi Su - 27 ) , and has standard flight instruments . At the rear of the cockpit is a 6 mm ( 0 . 24 in ) thick steel headrest , mounted on the rear bulkhead . The cockpit has a bathtub - shaped armoured enclosure of welded titanium sheets , with transit ports located in the walls . Guide rails for the ejection seat are mounted on the rear wall of the cockpit . The canopy hinges open to the right , and the pilot enters using the flip - down ladder . Once inside , the pilot sits low in the cockpit , protected by the bathtub assembly , which makes for a cramped cockpit . Visibility from the cockpit is limited , being a trade - off for improved pilot protection . Rearwards visibility is very limited , though a periscope is fitted on top of the canopy to compensate . On the left - hand rear side of the cockpit , a built - in ladder provides access to the cockpit , the upper part of the engine nacelles , and the wing . Avionics . The base model Su - 25 incorporates a number of key avionics systems . It has no TV guidance , but includes a distinctive nose - mounted laser rangefinder , that is hypothesized to provide for laser - based target designation capability . A DISS - 7 doppler radar is used for navigational purposes ; the Su - 25 can fly at night , in both visual and instrument meteorological conditions . The Su - 25 often has multiple radios installed for air - to - ground and air - to - air communications , including an SO - 69 identification - friend - or - foe ( IFF ) transponder . The aircraft ' s self - defence suite includes various measures , such as flare and chaff dispensers capable of launching up to 250 flares and dipole chaff . Hostile radar uses are guarded against via an SPO - 15 radar warning receiver . An airtight avionics compartment is behind the cockpit and in front of the forward fuel tank . The newer Su - 25TM and Su - 25SM models have an upgraded avionics and weapons suite , resulting in improved survivability and combat capability . Operational history . Soviet war in Afghanistan . The first Soviet Air Forces Su - 25 unit was the 200th Independent Attack Squadron , initially based at Sitalcay air base in the Azerbaijan Soviet Socialist Republic . The first eleven aircraft arrived at Sitalchay in May 1981 . On 19 July 1981 , the 200th Independent Attack Squadron was re - assigned to Shindand Airbase in western Afghanistan , becoming the first Su - 25 unit deployed to that country . Its main task was to conduct air strikes against mountain military positions and structures controlled by the Afghan rebels . Another Soviet Su - 25 unit was the 368th Attack Aviation Regiment , which was formed on 12 July 1984 , at Zjovtnevoye in Ukraine . It was soon also moved east to conduct operations over Afghanistan . Over the course of the Soviet war in Afghanistan , Su - 25s launched a total of 139 guided missiles of all types against Mujahideen positions . On average , each aircraft performed 360 sorties a year , a total considerably higher than that of any other combat aircraft in Afghanistan . By the end of the war , nearly 50 Su - 25s were deployed at Afghan airbases , carrying out a total of 60 , 000 sorties . Between the first deployment in 1981 and the end of the war in 1989 , 21 aircraft were lost in combat operations . Iran – Iraq War . The Su - 25 also saw combat during the Iran – Iraq War of 1980 – 1988 . The first Su - 25s were commissioned by the Iraqi Air Force in 1987 and performed approximately 900 combat sorties throughout the course of the war , carrying out the bulk of Iraqi air attack missions . During the most intense combat of the war , Iraqi Su - 25s were performing up to fifteen sorties per day each . In one recorded incident , an Iraqi Su - 25 was shot down by an Iranian Hawk surface - to - air missile , but the pilot managed to eject . This was the only confirmed successful Iranian attack against an Iraqi Su - 25 . After the war , Saddam Hussein decorated all of the Iraqi Air Force ' s Su - 25 pilots with the country ' s highest military decoration . Persian Gulf War . During the Gulf War ( Operation Desert Storm ) , the air superiority of the coalition forces was so great that the majority of Iraqi Su - 25s did not even manage to get airborne . On 25 January 1991 , seven Iraqi Air Force Su - 25s fled from Iraq and landed in Iran . On the evening of 6 February 1991 , two US Air Force F - 15C Eagle fighters of the 53rd Tactical Fighter Squadron , operating out of Al Kharj Air Base in Saudi Arabia , intercepted a pair of Iraqi MiG - 21s and a pair of Su - 25s . All four Iraqi aircraft were shot down , with both Su - 25s coming down in the desert not far from the Iraqi border with Iran . This was the Iraqi Su - 25 ' s only air combat of the war . First Chechen War . Russian Su - 25s were employed during the First Chechen War . Together with other Russian Air Force air assets , they achieved air supremacy for Russian Forces , destroying up to 266 Chechen aircraft on the ground . The entire Air Force assets committed to the Chechen campaign between 1994 and 1996 performed around 9 , 000 air sorties , with around 5 , 300 being strike sorties . The 4th Russian Air Army had 140 Su - 17 Ms , Su - 24 s and Su - 25s in the warzone supported by an A - 50 AWACS aircraft . The employed munitions were generally unguided bombs and rockets with only 2 . 3 % of the strikes using precision - guided munitions . In the first war , the Russian forces were not able to properly take advantage of the achieved air supremacy due to obsolete air tactics that focused the Air Force on useless tasks in this type of war such as Combat Air Patrols . The Russian air losses were low since no integrated air defense was fielded by the Chechens . The Russian forces lost four Su - 25s to various causes during the war . On 4 February 1995 , a Russian Su - 25 was shot down by antiaircraft fire over Belgatoi Gekhi , five kilometers southeast of Grozny . The pilot ejected , but died impacting the ground with his parachute not deploying on time . On 4 April 1996 , a Russian Su - 25 was shot down by a MANPADS during a reconnaissance flight over the village of Goiskoye . The pilot ejected and was recovered by a friendly helicopter returning to Khankala Airport , Grozny . On 5 May 1996 , a Russian Su - 25 was shot down near the village of Mairtup . It was the fifth Russian aircraft shot down since the start of the war in December 1994 . Both pilots were killed in the crash . Second Chechen War . Russian Air Force Su - 25s were extensively used during the Second Chechen War in particular during the first phase when Russian forces were invading the self - proclaimed Chechen Republic of Ichkeria . Up to seven Russian Su - 25s were lost , one to hostile fire . On 4 October 1999 , a Su - 25 was shot down by a MANPADS during a reconnaissance mission over the village of Tolstoy - Yurt killing its pilot . The wings of the aircraft were put on a pedestal in the central square in Grozny . Ethiopian - Eritrean War . Su - 25 attack aircraft were used by the Ethiopian Air Force to strike Eritrean targets . On 15 May 2000 , An Ethiopian Su - 25 was shot down by an Eritrean Air Force MiG - 29 , killing the pilot . 2001 insurgency in the Republic of Macedonia . Su - 25s were used by the Macedonian Air Force during the conflict against Albanian separatists . Beginning on 24 June 2001 , the aircraft made multiple attack runs against separatist positions . The most successful operation took place on 10 August 2001 , in the village of Raduša , when Su - 25s attacked Albanian militants who had ambushed and killed 16 Macedonian soldiers over the previous two days . War in Darfur . Sudan has used Su - 25s in attacks on rebel targets and possibly civilians in Darfur . Ivorian - French clashes . During the Ivorian Civil War , Su - 25s were used by government forces to attack rebel targets . On 6 November 2004 , at least one Ivorian Sukhoi Su - 25 attacked a unit of France ' s Unicorn peacekeeping forces stationed in Bouaké at 1300 , killing nine peacekeepers and a U . S . development worker , and wounding 37 soldiers . Shortly afterwards , the French military retaliated by attacking the air base in Yamoussoukro and destroyed the Ivorian air force , including its two Su - 25s . 2008 Russia – Georgia war . In August 2008 , Su - 25s were used by both Georgia and Russia during the 2008 Russia – Georgia war . Su - 25s of the Georgian Air Force participated in providing air support for troops during Battle of Tskhinvali and launched bombing raids on targets in South Ossetia . Russian military Su - 25s struck Georgian forces in South Ossetia , and undertook air raids on targets in Georgia . The Russian military officially confirmed the loss of three Su - 25 aircraft to the Georgian air defense , though the " Moscow Defense Brief " suggests four . Russia estimates that it destroyed three Georgian Su - 25s in the war , none confirmed by Georgia . The three Russian aircraft were reportedly downed by Georgian Buk - M1 air defence units . Georgian Su - 25s were able to operate at night . In early August 2008 , Russian Su - 25s attacked the Tbilisi Aircraft Manufacturing plant , where the Su - 25 is produced , dropping bombs on the factory ' s airfield . Iran . On 1 November 2012 , two Iranian Su - 25s fired at a USAF MQ - 1 Predator drone 16 nautical miles off the Iranian coast . The Iranian government has claimed that the drone violated its airspace . Variants . Su - 25 . The basic version of the aircraft was produced at Factory 31 , at Tbilisi , in the Soviet Republic of Georgia . Between 1978 and 1989 , 582 single - seat Su - 25s were produced in Georgia , not including aircraft produced under the Su - 25K export program . This variant of the aircraft represents the backbone of the Russian Air Force ' s Su - 25 fleet , currently the largest in the world . The aircraft experienced a number of accidents in operational service caused by system failures attributed to salvo firing of weapons . In the wake of these incidents , use of its main armament , the 240 mm S - 24 missile , was prohibited . In its place , the FAB - 500 500 kg general - purpose high - explosive bomb became the primary armament . Su - 25K . The basic Su - 25 model was used as the basis for a commercial export variant , known as the Su - 25K ( " Komercheskiy " ) . This model was also built at Factory 31 in Tbilisi , Georgia . The aircraft differed from the Soviet Air Force version in certain minor details concerning internal equipment . A total of 180 Su - 25K aircraft were built between 1984 and 1989 . Su - 25UB . The Su - 25UB trainer ( " Uchebno - Boyevoy " ) was drawn up in 1977 . The first prototype , called " T - 8UB - 1 " , was rolled out in July 1985 and its maiden flight was carried out at the Ulan - Ude factory airfield on 12 August of that year . By the end of 1986 , 25 Su - 25UBs had been produced at Ulan - Ude before the twin - seater completed its State trials and officially cleared for service with the Soviet Air Force . It was intended for training and evaluation flights of active - duty pilots , and for training pilot cadets at Soviet Air Force flying school s . The performance did not differ substantially from that of the single - seater . The navigation , attack , sighting devices and weapons - control systems of the two - seater enabled it to be used for both routine training and weapons - training missions . Su - 25UBK . From 1986 to 1989 , in parallel with the construction of the main Su - 25UB combat training variant , the Ulan - Ude plant produced the so - called " commercial " Su - 25UBK , intended for export to countries that bought the Su - 25K , and with similar modifications to that aircraft . Su - 25UBM . The Su - 25UBM is a twin seat variant that can be used as an operational trainer , but also has attack capabilities , and can be used for reconnaissance , target designation and airborne control . Its first flight was on 6 December 2008 and it was certified in December 2010 . It will enter operational use with the Russian Air Force later . The variant has a Phazotron NIIR Kopyo radar and Bars - 2 equipment on board . Su - 25UBM ' s range is believed to be 1 , 300 km and it may have protection against infra - red guided missiles ( IRGM ) , a minimal requirement on today ' s battle fields where IRGMs proliferate . Su - 25UTG . The Su - 25UTG ( Uchebno - Trenirovochnyy s Gakom " ) is a variant of the Su - 25UB designed to train pilots in takeoff and landing on a land - based simulated carrier deck , with a sloping ski - jump section and arrester wire s . The first one flew in September 1988 , and approximately 10 were produced . About half remained in Russian service after 1991 ; they were used on Russia ' s sole aircraft carrier , the . This small number of aircraft were insufficient to meet the training needs of Russia ' s carrier air group , so a number of Su - 25UBs were converted into Su - 25UTGs . These aircraft being distinguished by the alternative designation " Su - 25UBP " ( Uchebno - Boyevoy Palubny " ) — the adjective " palubnyy " meaning " deck " , indicating that these aircraft have a naval function . Approximately 10 of these aircraft are currently operational in the Russian Navy as part of the 279th Naval Aviation Regiment . Su - 25BM . The Su - 25BM ( " Buksirovshchik Misheney " ) is a target - towing variant of the Su - 25 whose development began in 1986 . The prototype , designated T - 8BM1 , successfully flew for the first time on 22 March 1990 , at Tbilisi . After completion of the test phase , the aircraft was put into production . The Su - 25BM target - tower was designed to provide towed target facilities for training ground forces and naval personnel in ground - to - air or naval surface - to - air missile systems . It is powered by an R - 195 engine and equipped with an RSDN - 10 long - range navigation system , an analogue of the Western LORAN system . Su - 25T . The Su - 25T ( Tankovy " ) is a dedicated antitank version , which has been combat - tested with notable success in Chechnya . The variant was converted to one - seater , with the rear seat replaced by additional avionics . It has all - weather and night attack capability . In addition to the full arsenal of weapons of the standard Su - 25 , the Su - 25T can employ the KAB - 500Kr TV - guided bomb and the semi - active laser - guided Kh - 25ML . Its enlarged nosecone houses the " Shkval " optical TV and aiming system with the " Prichal " laser rangefinder and target designator . It can also carry " Vikhr " laser - guided , tube - launched missiles . For night operations , the low - light TV " Merkuriy " pod system can be carried under the fuselage . Three Su - 25Ts prototypes were built in 1983 – 86 and 8 production aircraft were built in 1990 . With the introduction of a definitive Russian Air Force Su - 25 upgrade programme , in the form of Stroyevoy Modernizirovannyi " , the Su - 25T programme was officially canceled in 2000 . Su - 25TM ( Su - 39 ) . A second - generation Su - 25T , the " Su - 25TM " ( also designated " Su - 39 " ) , has been developed with improved navigation and attack systems , and better survivability . While retaining the built - in " Shkval " of Su - 25T , it may carry " Kopyo " ( rus . " Spear " ) radar in the container under fuselage , which is used for engaging air targets ( with RVV - AE / R - 77 missiles ) as well as ships ( with Kh - 31 and Kh - 35 antiship missiles ) . The Russian Air Force has received 8 aircraft as of 2008 . Some of the improved avionics systems designed for T and TM variants have been included in the " Su - 25SM " , an interim upgrade of the operational Russian Air Force Su - 25 , for improved survivability and combat capability . The Su - 25TM , as an all - inclusive upgrade programme has been replaced with the " affordable " Su - 25SM programme . Su - 25SM . The Su - 25SM ( " Stroyevoy Modernizirovannyi " ) is an " affordable " upgrade programme for the venerable Su - 25 , conceived by the Russian Air Force ( RuAF ) in 2000 . The programme stems from the attempted Su - 25T and Su - 25TM upgrades , which were evaluated and labeled as over - sophisticated and expensive . The SM upgrade incorporates avionics enhancements and airframe refurbishment to extend the Frogfoot ' s service life by up to 500 flight hours or 5 years . The Su - 25SM ' s all - new PRnK - 25SM " Bars " navigation / attack suite is built around the BTsVM - 90 digital computer system , originally planned for the Su - 25TM upgrade programme . Navigation and attack precision provided by the new suite is three times better of the baseline Su - 25 and is reported to be within 15 m ( 46 ft ) using satellite correction and 200 m ( 660 ft ) without it . A new KA1 - 1 - 01 Head - Up Display ( HUD ) was added providing , among other things , double the field of view of the original ASP - 17BTs - 8 electro - optical sight . Other systems and components incorporated during the upgrade include a Multi - Function Display ( MFD ) , RSBN - 85 Short Range Aid to Navigation ( SHORAN ) , ARK - 35 - 1 Automatic Direction Finder ( ADF ) , A - 737 - 01 GPS / GLONASS Receiver , Karat - B - 25 Flight Data Recorder ( FDR ) , Berkut - 1 Video Recording System ( VRS ) , Banker - 2 UHF / VHF communication radio , SO - 96 Transponder and a L150 " Pastel " Radar Warning Receiver ( RWR ) . The R - 95Sh engines have been overhauled and modified with an anti - surge system installed . The system is designed to improve the resistance of the engine to ingested powders and gases during gun and rocket salvo firing . The combination of reconditioned and new equipment , with increased automation and self - test capability has allowed for a reduction of pre - and post - flight maintenance by some 25 to 30 % . Overall weight savings are around 300 kg ( 660 lb ) . Su - 25SM weapon suite has been expanded with the addition of the Vympel R - 73 highly agile air - to - air missile ( albeit without helmet mounted cuing ) and the S - 13T 130 mm rockets ( carried in five - round B - 13 pods ) with blast - fragmentation and armour - piercing warheads . Further , the Kh - 25 ML and Kh - 29 L Weapon Employment Profiles have been significantly improved , permitting some complex missile launch scenarios to be executed , such as : firing two consecutive missiles on two different targets in a single attack pass . The GSh - 30 - 2 cannon ( 250 round magazine ) has received three new reduced rate - of - fire modes : 750 , 375 and 188 Rounds per Minute . The Su - 25SM was also given new BD3 - 25 under - wing pylons . The eventual procurement programme is expected to include between 100 and 130 kits , covering 60 to 70 percent of the RuAF active single - seat fleet , as operated in the early 2000s . By 2020 , 80 aircraft are to be modernised to SM version . By March 2013 , over 60 aircraft are to be upgraded . In February 2013 , ten new Su - 25SMs were delivered to the Air Force southern base , where operational training is being conducted . Su - 25KM . The Su - 25KM ( " Kommercheskiy Modernizirovannyy " ) , nicknamed " Scorpion " , is an Su - 25 upgrade programme announced in early 2001 by the original manufacturer , Tbilisi Aircraft Manufacturing in Georgia , in partnership with Elbit Systems of Israel . The prototype aircraft made its maiden flight on 18 April 2001 at Tbilisi in full Georgian Air Force markings . The aircraft uses a standard Su - 25 airframe , enhanced with advanced avionics including a glass cockpit , digital map generator , helmet - mounted display , computerised weapons system , complete mission pre - plan capability , and fully redundant backup modes . Performance enhancements include a highly accurate navigation system , pinpoint weapon delivery systems , all - weather and day / night performance , NATO compatibility , state - of - the art safety and survivability features , and advanced onboard debriefing capabilities complying with international requirements . It has the ability to use Mark 82 and Mark 83 laser - guided bombs and air - to - air missiles , the short - range Vympel R - 73 . Su - 28 . The Sukhoi Su - 28 ( also designated " Su - 25UT " – " Uchebno - Trenirovochnyy " ) is an advanced basic jet trainer , built on the basis of the Su - 25UB as a private initiative by the Sukhoi Design Bureau . The Su - 28 is a light aircraft designed to replace the Czechoslovak Aero L - 39 Albatros . Unlike the basic Su - 25UB , it lacks a weapons - control system , built - in cannon , weapons hardpoints , and engine armour . Accidents . The Su - 25 has been involved in the following aviation accidents .