S5.142
The S5.142 (AKA DST-25) is a liquid pressure-fed rocket engine burning N2O4/UDMH with an O/F of 1.85.[1] It is used for crew-rated spacecraft propulsion applications.[5] It was used in KTDU-80 propulsion module from the Soyuz-TM to the Soyuz-TMA-M, as the low thrust thruster (DPO-M).[3] As of the Soyuz MS, KTDU-80 does not use DPO-M anymore.[6]
| Country of origin | Russia | 
|---|---|
| Date | 1990-1996 | 
| First flight | 1996-02-21 (Soyuz TM-23) | 
| Designer | KB KhIMMASH | 
| Application | attitude control thruster | 
| Predecessor | 11D427M | 
| Status | Retired | 
| Liquid-fuel engine | |
| Propellant | N2O4 / UDMH | 
| Mixture ratio | 1.85 | 
| Cycle | pressure fed | 
| Configuration | |
| Chamber | 1 | 
| Nozzle ratio | 45 | 
| Performance | |
| Thrust, vacuum | 25 N (5.6 lbf) | 
| Chamber pressure | 0.88 MPa (128 psi) | 
| Specific impulse, vacuum | 285 s (2.79 km/s) | 
| Burn time | 25,000 seconds | 
| Restarts | 300,000 | 
| Dimensions | |
| Length | 180 mm (7.1 in) | 
| Diameter | 136 mm (5.4 in) | 
| Dry weight | 0.9 kg (2.0 lb) | 
| Used in | |
| KTDU-80 | |
| References | |
| References | [1][2][3][4][5][6] | 
The S5.142 generates 25 N (5.6 lbf) of thrust with a chamber pressure of 0.88 MPa (128 psi) and a nozzle expansion of 45 that enables it to achieve a specific impulse of 285 s (2.79 km/s).[1] It is rated for 300,000 starts with a total firing time of 25,000 seconds and can do single burns from 0.03 seconds to 4,000 seconds. Each unit weights 0.9 kg (2.0 lb).[1][5]
Versions
    
This engine has been used in manned Russian space program since the Soyuz TM-23.[1] There are two versions:[4]
See also
    
    
References
    
- "ЖРДМТ от 0,5 кгс до 250 кгс" [Small thrust jet engine from 0.5 kgf to 250 kgf] (in Russian). KB KhIMMASH. Retrieved 2015-07-25.
- "Двигатели 1944-2000: Аавиационные, Ракетные, Морские, Промышленные" [Aviadvigatel 19442-2000: Aviation, rocketry, naval and industry] (PDF) (in Russian). pp. 75–81. Retrieved 2015-07-25.
- Pillet, Nicolas. "Le système de propulsion du vaisseau Soyouz" [The propulsion system of the Soyuz spacecraft] (in French). Kosmonavtika.com. Retrieved 2015-07-14.
- "Основные двигатели разработки КБХМ" [The main engines produced by KbKhA] (in Russian). Retrieved 2015-07-25.
- RKK Energia (June 1999). "3.17. Комбинированная Двигательная Установка (КДУ) (Combined Propulsion System)". Soyuz Crew Operations Manual (SoyCOM) (ROP-19) Final. NASASpaceFlight.com. pp. 122–129.
- Zak, Anatoly (2016-07-07). "Propulsion system for the Soyuz MS spacecraft". Russian Space Web. Retrieved 2016-07-06.
