DR.NAMBI NARAYANAN SIRS' ENGINE EXPLINATION

 The Vikas (a portmanteu from initials of VIKRAM AMBALAL SARABHAI ) is a family of liquid fuelled rocket engine conceptualized and designed by the Liquid propulsion system centere  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 satelite launch vehicle (PSLV) and the Geosynchronous satellite launch vehicle    (GSLV) series of expendable launch vehicles 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 GSLV MARK III . The propellant loading for Vikas engine in PSLV, GSLV Mark I and II is 40 tons, while in GSLV Mark III is 55 tons.

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.