Glitch holds up India's first navigation satellite launch

An electrical glitch in the rocket Saturday forced the Indian space agency to put off its first regional navigation satellite (IRNSS-1A) launch June 12 by two weeks from its spaceport at Sriharikota.

"During the checks of the polar launch satellite vehicle rocket (PSLV-C22), an anomaly was observed in one of the electro-hydraulic control actuators in the second stage," the state-run Indian Space Research Organisation (ISRO) said in a statement here.

As the replacement of the actuator will need two weeks of activity at the rocket's launch pad and the vehicle assembly area, the satellite launch has been delayed by a fortnight and will be rescheduled to June 26 from the spaceport, about 90 km from Chennai.

"Though the satellite has gone through all electrical checks after it was integrated with the rocket and was ready for propellant filling, the timely detection of the glitch has made us revisit the critical component," the statement added.

The 1,425 kg navigational satellite is intended to provide terrestrial, aerial and marine navigation services and help in disaster and fleet management across the region, after it is positioned in geostationary equatorial orbit about 36,000 km away from the earth.

"A constellation of the seven navigation satellites system will provide two types of services - standard positioning service for civilian use and restricted service, which is encrypted for authorised users (military and security)," a space official said.

In the run-up to the scheduled launch, the space agency opened May 28 a navigation centre in its Deep Space Network complex at Byalalu, about 40 km from this tech hub.

"The navigation centre will function as the main ground station for the regional navigation satellite system, as it is equipped with high precision atomic clocks and transmit navigation signals to multiple users round the clock," the official noted.

The navigation centre will also be responsible for the time reference, generation of navigation messages and monitoring and control of ground facilities, including ranging stations.

Key to the global positioning system (GPS)-based navigation support is the time reference to which all ground-based systems and satellite clocks are synchronised.

A network of 21 ranging stations located across the country will provide data for the orbit determination of the satellites and monitoring of the navigation signal.

The navigational satellites will provide an accurate real time position, navigation time (PNT) services to users in air, sea and land on a variety of platforms under all weather conditions.