With an eye on cutting costs and having on demand launch, ISRO on Sunday said it was preparing Small Satellite Launch Vehicle rockets to launch payloads in three days with the help of just three to six people.

"The interesting aspect of the Small Satellite Launch Vehicle (SSLV) is that it can be readied on demand with a minimum launch infrastructure," ISRO chairman K Sivan said.

He said it takes about 300 to 400 people between 45 to 60 days to prepare major satellite vehicles.

But the SSLV would require only 72 hours and three to six people.

"We need to integrate the vehicle and launch it. It is innovative and provides an opportunity for commercial launches for other countries. Autonomy is more in this vehicle.

Already the vehicle is in the design phase... there is an opportunity for commercial launch," he said.

Sivan revealed ISRO's commercial plans during an interaction with reporters on the sidelines of a function to mark the 127th birth anniversary of Dr Vikram Sarabhai, the architect of India's space mission.

Sivan said the important demonstration flight of SSLV would be carried out sometime in May or June next year.

"The speciality of this mission is the cost of the vehicle, which is one-tenth of PSLV. The payload will be 500 to 700 KG and it will be launched in a lower orbit.

The length of the vehicle would be 34 metres, with a 2-metre diameter. It is an on-demand launch with a minimum launch infrastructure," said Sivan.

Commercial production of this vehicle will be taken up by Antrix the commercial arm of ISRO, once the design is complete and development was ready by mid 2019, he added.