NVS-03 operated with three pyro valves open to overcome past technical hurdles, says ISRO chief

ISRO chief V Narayanan said on Saturday that the NVS-03 satellite was operated with “three pyro valves open” to ensure mission reliability and overcome technical hurdles encountered in the past.

Pyro valves are crucial in spacecraft propulsion, and it may be recalled that the NVS-02 (launched in 2025), the second spacecraft in the NVS series, was a failure.

A high-level panel, after thorough analysis, concluded that "the drive signal did not reach the pyro valve of the oxidiser line of the engine meant for orbit raising."

In February 2026, ISRO, quoting the panel, announced that the most likely cause was the disengagement of at least one contact (in each of the main and redundant paths) of the connector.

Against this background, Narayanan said that with four satellites, including NVS-01 now active in India's navigation satellite system, ISRO plans to launch NVS-04 in five months, and NVS-05 in 10 months to further bolster the constellation.

Narayanan highlighted the exceptional accuracy of the flight. "Against (the planned) perigee (point when it is closest to the Earth) of 170.36 km; we have got 170.31 kilometres," Narayanan said.

"Against (the planned) Apogee (point farthest away from the Earth) of 37,247 kilometres, we achieved 38,080 kilometres," he noted. "This is one of the best accuracy of any of the launch vehicles in the world we can think of," he added.

The successful deployment has restored India's NavIC (Navigation with Indian Constellation) to its minimum operating configuration of four satellites, bolstering both strategic and civilian location services across the subcontinent.

The NVS-03 satellite weighs 2,240 kg.

Executing its fastest-ever turnaround for a heavy-lift rocket, the ISRO successfully placed the next-generation navigation satellite NVS-03 into a highly precise orbit using the GSLV-F18 launch vehicle early Saturday.

He said: "To ensure mission reliability and bypass previous technical hurdles, ISRO flew the satellite with three pyro valves already open. Narayanan revealed that this bold technical decision was validated after rigorous vibration and shock testing by a national-level committee chaired by former ISRO chief Kiran Kumar."

Elaborating on NavIC's civilian applications, the ISRO chief said 10,400 locomotives and 64,000 fishing vessels are currently tracked in real-time. Under the Pradhan Mantri Matsya Sampada Yojana, the agency aims to expand this to 1 lakh fishing vessels within the next six months. In total, 15 lakh tracking devices have been fitted across vehicles. When asked when NavIC would be available on civilian mobile phones, Narayanan stated this would happen once the full seven-satellite constellation is completed.

Looking ahead to a packed manifest, the ISRO Chairman outlined the space agency's immediate goals. ISRO plans to accomplish five more launches during this financial year, which will include the first uncrewed Gaganyaan mission (G1) and small satellite missions.