| Manufacturer | TsSKB-Progress |
|---|---|
| Country of origin | Russia |
| Used on | Soyuz-U |
| Associated stages | |
| Derivatives | Volga |
| Launch history | |
| Total launches | 6[1] |
| Successes (stage only) | 6 |
| First flight | 9 February 1999 Soyuz-U (Globalstar 23/36/38/40) |
| Last flight | 22 November 1999 Soyuz-U (Globalstar 29/34/39/61) |
| General characteristics[2][3] | |
| Height | 2.56 m (8 ft 5 in) |
| Diameter | 2.72 m (8 ft 11 in) |
| Empty mass | 820 kg (1,810 lb) |
| Gross mass | 3,164 kg (6,975 lb) |
| Propellant mass | 2,310 kg (5,090 lb) |
| Powered by | 1 ×S5.144 |
| Maximum thrust | 2.943 kN (662 lbf) |
| Specific impulse | 326 s (3.20 km/s) |
| Burn time | Up to 600 seconds (up to 50 starts) |
| Propellant | N2O4 /UDMH |
TheIkar was a Russian rocketupper stage introduced byTsSKB Progress in 1999 for use with itsSoyuz-U rocket. It was derived from the propulsion module which had been used successfully on more than 30Yantar reconnaissance satellites, leveraging existing equipment and subsystems to minimize new development. Modifications were limited to updates in command and control systems and adjustments to mechanical and electrical interfaces with payloads.[3]
Weighing 820 kilograms (1,810 lb), the Ikar was situated beneath the payload fairing. It featured an in-flight restart capability of up to 50 times, enabling the deployment of multiple satellites into different orbits. The stage could operate autonomously or be controlled from the ground. It was powered byS5.144 engine, delivering a vacuum thrust of 2.943 kilonewtons (662 lbf), supported by 16vernier thrusters for precise flight control. The propulsion system usedunsymmetrical dimethylhydrazine (UDMH) fuel anddinitrogen tetroxide (N2O4) as its oxidizer.[3][4][5]
The Ikar could deliver payloads of 750 to 3,920 kilograms (1,650 to 8,640 lb) to orbits between 250 and 1,400 kilometres (160 and 870 mi) in altitude. While its performance was lower than that of the competingFregat upper stage, the Ikar offered more precise maneuvering capabilities and a longer autonomous operation time.
The Ikar was used in six launches in 1999, each carrying fourGlobalStar satellites.[1] It was replaced by the improvedVolga upper stage, which remains in use on theSoyuz-2 rocket.
 | This rocketry article is astub. You can help Wikipedia byexpanding it. |