By Express News Service

THIRUVANANTHAPURAM: If things go as planned, the Indian Space Research Organisation (ISRO) will flight-test the semi-cryogenic engine, which uses refined kerosene as propellant, by 2021.

With the success of the Geosynchronous Satellite Launch Vehicle Mk-III (GSLV Mk-III), ISRO’s Liquid Propulsion Systems Centre (LPSC) here at Valiyamala is now focusing on the next level - the development of the much-delayed semi-cryogenic technology.

Unlike the cryogenic engine which uses a combination of liquid hydrogen (LH2) and liquid oxygen (LOX) as propellant, the semi-cryogenic engine replaces liquid hydrogen with refined kerosene (Isrosene as ISRO calls it). LOX will be retained as oxidiser.

"Various tests are in progress on the engine. Of the four turbo pumps in it, three have undergone tests at the ISRO Propulsion Complex, Mahendragiri. We plan to have the engine ready by 2019 end, the stage by 2020-end and the first flight by 2021,’’ S Somanath, director, LPSC, said.

LPSC had developed the cryogenic engine for the GSLV Mk-II and the much powerful one for the GSLV Mk-III. The idea is to replace the second stage of the GSLV Mk-III, which now uses a liquid stage, with the semi-cryo. The rocket will retain the cryogenic upper, third stage.

The advantage of inducting the semi-cryogenic stage is the payload capacity of the GSLV Mk-III will increase from four tonnes to six tonnes. Using refined kerosene as fuel has quite a few advantages: It is eco-friendly and cost-effective.

Also, unlike liquid hydrogen - which has to be stored at (-)253 degree Celsius, it is stable at normal temperature. The Union Cabinet had cleared the semi-cryogenic engine project in 2008 at an estimated cost of Rs 1798 crore. Although the idea was to develop the technology 2014, the project got delayed.

Fingers crossed

Semi-cryogenic engine uses refined kerosene as propellant

It’s eco-friendly and cheaper

The Union Cabinet had cleared the project in 2008

ISRO hopes to flight-test it in 2021

Engine to be ready by 2019-end