ISRO to use PSLV stage four as orbital platform, create history

Describing the development, an ISRO scientist, on condition of anonymity, said that this was the first time in the world that such a technique is being used.

Published: 18th January 2019 06:11 AM  |   Last Updated: 18th January 2019 06:11 AM   |  A+A-

ISRO, Satellite, Rocket

Image used for representational purpose only. (File | PTI)

Express News Service

BENGALURU:  When India’s Polar Satellite Launch Vehicle (PSLV) with its new configuration — PSLV-DL — is launched from Satish Dhawan Space Centre in Sriharikota later this month, Indian Space Research Organisation (ISRO) will aim to achieve a first in the history of satellite technology. 

Unlike other launch vehicles, where each stage of the launcher plunges back to Earth, the last stage of this launcher will serve as an ‘orbital platform’ and will help in a variety of tasks designed for the satellite mounted on the platform. The newly configured PSLV C-44 will be launched into orbit carrying two satellites on January 24.

Describing the development, an ISRO scientist, on condition of anonymity, said that this was the first time in the world that such a technique is being used. “Only India could have done it as our primary objective is to maximise the benefits with the resources available with us,” he said.

In a normal launch vehicle, each stage falls off after fuel completes burn-off, triggering the burn in the next stage. The PSLV-DL, which is a four-stage launcher, will follow the same pattern, except for the fact that the fourth stage won’t fall off after launching the satellite into its orbit. 

“The fourth stage will serve as a platform or a vehicle for the satellite. For instance, we can deploy solar panels or other tools to aid the satellite riding on the platform or to manoeuvre it to different positions along its orbit,” he said.

The new variant will have alternating solid and liquid stages, with the last stage of the launch vehicle containing both solid and liquid fuel. PSLV-C44 will launch KalamSat — a student satellite — and Microsat-R — an imaging satellite. While Microsat-R will be launched into a different orbit, KalamSat, designed for communication capabilities, will be the first to use the fourth stage as a platform.

-After launch, when the rocket lifts off for a few kms, the first stage detaches and falls back to earth.
-Second and third stages too fall off one after the other.
-Normally, the fourth stage firing takes the satellite close to its orbit and releases before falling back to earth.
-For the first time, the fourth stage will remain with satellite throughout its mission life
-Fourth stage will be provided with solar panels and will use its boosters for any changes in orbit.
-No space agency in the world has ever used a fourth stage booster for this purpose.


Disclaimer : We respect your thoughts and views! But we need to be judicious while moderating your comments. All the comments will be moderated by the editorial. Abstain from posting comments that are obscene, defamatory or inflammatory, and do not indulge in personal attacks. Try to avoid outside hyperlinks inside the comment. Help us delete comments that do not follow these guidelines.

The views expressed in comments published on are those of the comment writers alone. They do not represent the views or opinions of or its staff, nor do they represent the views or opinions of The New Indian Express Group, or any entity of, or affiliated with, The New Indian Express Group. reserves the right to take any or all comments down at any time.

flipboard facebook twitter whatsapp