Sukhoi Su-57 at the Russian Khmeimim air base in Syria. The aircraft were deployed along with four Sukhoi Su-35 fighters, four Sukhoi Su-25s, and one Beriev A-50 AEW&C aircraft. Three days later two more Su-57s were reported to have arrived in Syria. The deployment was criticised by some experts as overly risky, especially after reports of drones attack at Khmeimim air base.Military correspondent of "Komsomolskaya Pravda" was cited as saying that according to his information the Su-57s have "excellently" carried out their mission in Eastern Ghouta. On 1 March 2018, the Russian Defence Minister Sergey Shoygu confirmed that the two Su-57s indeed
Sukhoi-Gulfstream S-21 Sukhoi-Gulfstream S-21 Sukhoi-Gulfstream S-21 was a projected Russian-American supersonic business jet. In the early 1990s, Gulfstream Aerospace and the Sukhoi Design Bureau began a joint effort to develop a supersonic small business jet, code named the S-21. Due to questionable market demand for commercial supersonic air travel, commitment to the project weakened and delays mounted. Gulfstream eventually dissolved the partnership, although Sukhoi continued work on the S-21. The S-21 would be capable of sustained cruise at Mach 2+ and much research and development has gone into the management of the troublesome transonic effects phenomena associated with near Mach 1 air