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S5.142

9/3/2026

The S5.142 (AKA DST-25) is a liquid pressure-fed rocket engine burning N2O4/UDMH with an O/F of 1.85. It is used for crew-rated spacecraft propulsion applications. It was used in KTDU-80 propulsion module from the Soyuz-TM to the Soyuz-TMA-M, as the low thrust thruster (DPO-M). As of the Soyuz MS, KTDU-80 does not use DPO-M anymore. The S5.142 generates 25 N (5.6 lbf) of thrust with a chamber pres

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The S5.142 (AKA DST-25) is a liquid pressure-fed rocket engine burning N2O4/UDMH with an O/F of 1.85. It is used for crew-rated spacecraft propulsion applications. It was used in KTDU-80 propulsion module from the Soyuz-TM to the Soyuz-TMA-M, as the low thrust thruster (DPO-M). As of the Soyuz MS, KTDU-80 does not use DPO-M anymore. 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). 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).

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This article is an automated import of the Wikipedia article "S5.142", available at https://en.wikipedia.org/wiki/S5.142 . Text is licensed under CC BY-SA 4.0.