by 1995; two static-test aircraft was also constructed (T10M-0 and T10M-4). The aircraft did not enter mass production. Su-37Technology demonstrator, converted from the eleventh developmental Su-27M (T10M-11). The Su-37 featured a digital fly-by-wire flight-control system, a glass cockpit, the N011M radar, and AL-31FP engines with thrust-vectoring nozzles. The aircraft was later fitted with standard-production AL-31F engines, and had its flight-control system and cockpit systems revised. Su-35UB Two-seat trainer designed and built by KnAAPO. The single aircraft (T-10UBM-1) featured the canards and taller vertical tails of the Su-27M and a forward fuselage similar to the Su-30MKK. The Su-35UB also shared the avionics suite of the Su-30MKK, although it had a different fly-by-wire flight-control system to accommodate the canards. The aircraft was powered by AL-31FP engines with thrust-vectoring nozzles. Although a training aircraft, the Su-35UB was designed to be fully combat-capable. Su-35BM Single-seat fighter that is a major redesign of the original Su-27. The type features significant modifications to the airframe, including the removal of canards and dorsal air brake as found on the Su-27M. It features the updated N035 Irbis-E radar and a redesigned cockpit. The aircraft is powered by thrust-vectoring AL-41F1S turbofan engines that are capable of supercruise. Also known as T-10BM (Bolshaya Modernizatsiya, "Major Modernization"), Su-35BM is not the actual designation used by Sukhoi, who markets the aircraft as "Su-35". Su-35S Designation of production T-10BM design for the Russian Air Force. According to Aviation Week & Space Technology, "S" stands for Stroyevoy ("Combatant"). Operators People's Liberation Army Air Force – 24 aircraft in inventory. 6th Aviation Brigade – Suixi air base, Guangdong Russian Air Force – 110 aircraft in inventory as of December 2022. The third order for 30 aircraft finalised in August 2020 is to increase the total number to 128. 23rd Fighter Aviation Regiment – Dzyomgi Airport, Khabarovsk Krai 22nd Guards Fighter Aviation Regiment – Centralnaya Uglovaya Air Base, Primorsky Krai 159th Fighter Aviation Regiment – Besovets Air Base, Republic of Karelia 790th Fighter Aviation Regiment – Borisovsky Khotilovo Air Base, Tver Oblast 4th Centre for Combat Employment and Retraining of Personnel – Lipetsk Air Base, Lipetsk Oblast 929th State Flight-Test Centre – Vladimirovka Air Base, Astrakhan Oblast Khmeimim Air Base, Latakia, Syria 24 on order for IRIAF or IRGC-AF Notable accidents The fourth Su-35BM prototype was destroyed in a high-speed taxi run on 26 April 2009 due to brake failure. The aircraft crashed into the barrier