Isro to use own cryogenic technology for tomorrow’s INSAT-3DR launch

India will for the first time be using an indigenous cryogenic engine on an operational GSLV flight when the Indian Space research Organisation (Isro) launches a GSLV-MkII rocket to place one of the heaviest satellites in the INSAT/GSAT series on orbit tomorrow.

The GSLV MkII rocket powered by indigenous cryogenic engine CE-7.5 will be used to launch the INSAT-3DR satellite, which has a mass of 2,211 kg, including 1,255 kg of propellants.

The GSLV-MkII rocket will lift off from the second launch pad at the Sriharikota spaceport on 8 September at 4.10 pm and place the INSAT-3DR satellite on a geostationary transfer orbit around Earth.

The mission designated F05, will be Isro's ninth flight using cryogenic engines after a failed test in 2001. Eight flights have been conducted after that over the following 14 years. These included five using Russian cryogenic engine onboard and three others using indigenously developed ones. Of these, three succeeded, four failed and one was a partial success.

Isro successfully test-flew a rocket using indigenously developed cryogenic engine in January 2014.

In tomorrow's launch, the cryogenic engine will be used in the third or upper stage of the 3-stage GSLV rocket, which will carry the 2,211kg INSAT-3DR, which is an advanced weather satellite.

Isro scientists are now confident about the technology and they have declared that Thursday's launch will not be testing any engine parametres and that the only test is about accuracy of delivering the payload with precision.

The GSLV rocket has three variants, which include Mk-I, Mk-II and Mk-III. All three have a solid-fuel first stage and a liquid-fuel second stage. The Mk-I uses cryogenic engines of Russian make for the third stage.

The Mk-II uses four liquid-fuel strap-on boosters in addition to the first stage and the CE-7.5 indigenous cryogenic engine for the third. The Mk-III will use two solid-fuel boosters for the first stage and the CE-20 indigenous cryogenic engine for the third.

Isro had planned to develop a cryogenic engine for use in its rockets as far back as in 1986. But the selection of a partner from erstwhile Soviet Union over costly US and French technology proved disastrous for India's cryogenic quest.

Isro's selection of a company called Glavkosmos from the erstwhile Soviet Union, annoyed the US, which imposed sanctions on India and Russia after Isro and the Russian company refused to call off their deal.

Eventually, the Boris Yeltsin government in Russia pressured Glavkosmos to call off its partnership leaving 

Isro to fend for itself. But, the seven cryogenic engines supplied by Glavkosmos helped Isro to develop indigenous engines.

The cryogenic engine will allow GSLV to lift upwards of 1,500 kg to the geostationary transfer orbit. The PSLV rocket cannot reach this orbit with anything heavier than 1,400 kg.

The INSAT-3DR satellite is a follow up of INSAT-3D satellite, which was launched in 2013. Both are meteorological satellites and are upgrades of the KALPANA-1 and the INSAT-3A. KALPANA-1 and INSAT-3A satellites.

The F05 mission on 8 September will see the GSLV-MkII launch the INSAT-3DR into the geostationary transfer orbit. From there, the satellite will use its built-in propulsion systems to manoeuvre into its eventual geosynchronous orbit.

The INSAT-3DR will be capable of mapping vertical changes of humidity, temperature and ozone content in Earth's atmosphere measurements – as well as capture better images of night-time clouds, and better measure sea surface temperature. Like INSAT-3D, the INSAT-3DR will also include a search-and-rescue transponder, used to pinpoint the location of distressed vessels at sea.

The 3D will operate until 2021. The 3DR will last till around 2024. A second successor, INSAT-3DS, is expected to operate from 2022 to 2029. The 3B and 3C are not operational.