Sukhoi-Gulfstream S-21 was a projected Russian-American supersonic business jet.
In the early 1990s, Gulfstream Aerospace and the Sukhoi Design Bureau of Moscow 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 wavered 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 associated with near Mach 1 air speeds.
Specifications (S-21) 
- Crew: 2
- Capacity: 6–10
- Length: 124.2 ft (37.86 m)
- Wingspan: 65.4 ft (19.93 m)
- Wingsweep: 32° unswept (68° swept)
- Height: 27.1 ft (8.26 m)
- Empty weight: 54,167 lb (24,570 kg)
- Useful load: 2,000 lb (907 kg)
- Max. takeoff weight: 114,200 lb (51,800 kg)
- Fuel: 58,465 lb (26,519 kg)
- Powerplant: 3 × Aviadvigatel D-21A1 turbofan, 16,535 lbf (73.55 kN) each
- Maximum speed: 1,483 mph (2,386 km/h)
- Cruise speed: 1,483 mph (2,386 km/h)
- Range: 4,600 mi (7,403 km)
- Range (Mach 1.4): 2,715 mi (4,369 km)
- Range (Mach 0.95): 4,600 mi (7,403 km)
- Service ceiling: 63,900 ft (19,477 m)
- Thrust/weight: 0.43
See also 
- Aircraft of comparable role, configuration and era
- Related lists
External links 
Media related to Sukhoi S-21 at Wikimedia Commons