The deployment took place in two stages -- first by firing an explosive device to release the sail-boom assembly and later operating a motor for about 15 minutes to ensure a controlled deployment, an ISRO press release here today said.

With this, the satellite is in the 3-axle stabilised final configuration with earth orientation, and the stage is set for turning on the payloads, the release said.

The sail and boom are indigenously designed, developed and manufactured at ISRO Satellite Centre, Bangalore, followed by extensive testing in simulated zero-gravity conditions.

The release said this deployment was preceded by turning on the momentum wheels onboard the satellite, and running them up to a speed of 4,800 revolutions per minute.

The momentum wheels are used for maintaining the precise orientation of the satellite required for thecommunication and meteorological payloads.

During launch, the sail-boom assembly is kept compactly packed. It just occupies about 1/50th of its final deployed length. The boom is made of ultra light-weight glass fibre structure weighing about 3.5 kg. The sail measuring 2 m across and 5 m tall weighs less than a kilogram.

Insat-2E carries a meteorological payload, which requires the detector to be maintained at an extremely low pressure. This precludes the use of solar arrays symmetrically on both north and south faces. To counteract the torque generated by the sun's radiation falling on the solar array on the south side, the solar sail mounted on a boom is incorporated in the design of Insat-2E on the north side.