Vikas (rocket engine)
Indian rocket engine
The Vikas engine (a portmanteau from initials of VIKram Ambalal Sarabhai ) is a family of hypergolic liquid fuelled rocket engines conceptualized and designed by the Liquid Propulsion Systems Centre in the 1970s. The design was based on the licensed version of the Viking engine with the chemical pressurisation system. The early production Vikas engines used some imported French components which were later replaced by domestically produced equivalents. It is used in the Polar Satellite Launch Vehicle (PSLV), Geosynchronous Satellite Launch Vehicle (GSLV) and LVM3 for space launch use.
Vikas engine is used to power the second stage of PSLV, boosters and second stage of GSLV Mark I and II and also the core stage of LVM3. The propellant loading for Vikas engine in PSLV, GSLV Mark I and II is 40 tons, while in LVM3 is 55 tons.
01History
In 1974, Societe Europeenne de Propulsion agreed to transfer Viking engine technology in return for 100 man-years of engineering work from ISRO. The first engine built from the acquired technology was tested successfully in 1985 by Nambi Narayanan and his team at ISRO and named it Vikas. Most components for the VIKAS engine were made formerly by KELTEC, before being subsumed by Brahmos Aerospace.

02Technical details
The engine uses up about 40 metric tons of UDMH as fuel and nitrogen tetroxide (N2O4) as oxidizer with a maximum thrust of 725 kN. An upgraded version of the engine has a chamber pressure of 58.5 bar as compared to 52.5 bar in the older version and produces a thrust of 800 kN. The engine is capable of gimballing.
For launches from 2018 a 6% increased thrust version of the Vikas engine was developed. It was demonstrated on 29 March 2018 in the GSAT 6A launch second stage. It will be used for the four Vikas engines first-stage boosters on future missions. Tests were conducted on the Vikas engine in 2025 for future applicability to VTVL technologies.
03Variants
| Type | Nozzle
Diameter (m) |
Length
(m) |
Nozzle
Area Ratio |
Chamber
pressure (MPa) |
Fuel | Mix Rate | Flow rate
(kg/s) |
Thrust (kN) | Specific Impulse (Ns/kg) | Launcher Stages | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea Level | Vacuum | Sea Level | Vacuum | |||||||||
| Booster/first stage | ||||||||||||
| Vikas-1 | ~1.00 | ~2.75 | 13.9 | 5.30 | UDMH / N2O4 | 1.86 | 246.9 | 600.5 | 680.5 | 2432 | 2756 | GSLV Mk.I L40H Strapon |
| Vikas-1+ | ~1.00 | ~2.75 | 13.9 | 5.30 | UH 25 / N2O4 | 1.87 | 271 | 677.7 | 765.5 | 2501 | 2824 | GSLV Mk.II L40H Strapon |
| Vikas-X | ~1.80 | ~3.75 | UH 25 / N2O4 | 285.7 | 736.8 | 821.0 | 2579 | 2873 | LVM3 L110 stage | |||
| Second stage | ||||||||||||
| Vikas-2 | ~1.50 | ~3.50 | 5.35 | UDMH / N2O4 | 1.86 | 249.8 | - | 725.0 | 2903 | GSLV Mk.I GS2 stage, PSLV PS2 stage | ||
| Vikas-2B | ~1.80 | ~3.70 | 5.85 | UH 25 / N2O4 | 1.71 | 271.6 | - | 804.5 | 2962 | GSLV Mk.II GS2 stage, PSLV PS2 stage | ||
| References: | ||||||||||||
Sources and credits
This article is adapted from the Wikipedia article “Vikas (rocket engine)”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.
Images, from Wikimedia Commons:
- Vikas engine of ISRO.JPG by Anirvan Shukla, CC BY-SA 3.0
- PSLV C50 second stage with Vikas engine.jpg by ISRO, GODL-India
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