The Indian Space Research Organisation (ISRO) is targeting the launch of its navigation satellite NVS-03 between October 15 and 20, a mission that could reactivate NavIC’s standalone positioning service and provide a major boost to India’s security forces.

India’s Navigation with Indian Constellation (NavIC), formerly known as the Indian Regional Navigation Satellite System (IRNSS), currently has only three operational satellites: IRNSS-1B, IRNSS-1I and NVS-01.

The constellation requires at least four operational satellites to provide a standalone positioning service. As a result, NavIC’s positioning capability is presently unavailable, although its timing service remains functional.

This limitation affects the armed forces’ ability to use an indigenous navigation network for missile navigation, precision positioning, warship coordination, troop movement and combat-aircraft operations.

NVS-03 is the next satellite in NavIC’s second-generation constellation. It is expected to be launched aboard a GSLV Mk II rocket from the Satish Dhawan Space Centre in Sriharikota.

The launch campaign reportedly began on September 14, with the first stage of the GSLV MK-II already stacked. NVS-03 is also understood to be ready and positioned at the spaceport, reducing the possibility of a delay caused by satellite readiness.

Isro has not successfully launched a navigation satellite since May 29, 2023, when NVS-01 was placed in orbit.

The subsequent NVS-02 mission, launched aboard GSLV-F15 on January 29, 2025, failed to reach its designated orbit. The satellite was injected into an elliptical transfer orbit measuring approximately 170 km by 37,785 km, with an inclination of 20.8 degrees.

After separation from the launch vehicle, NVS-02 successfully deployed its solar panels and stabilised its attitude. However, its orbit-raising manoeuvre could not be carried out because the propulsion system failed to ignite.

An investigation by Isro’s apex committee traced the problem to the pyro system. The drive signal did not reach the pyro valve in the oxidiser line of the engine intended for orbit-raising operations.

The committee concluded that at least one contact in each of the main and redundant connector paths had probably disengaged. Consequently, the electrical command needed to activate the pyro valve did not reach the engine, despite the system’s built-in redundancy.

Isro has said that corrective measures recommended by the committee have been implemented to improve redundancy and reliability in future pyro-system operations. The measures were also incorporated and tested in subsequent spacecraft systems.

A successful NVS-03 mission would restore NavIC’s basic stand-alone positioning service by taking the constellation back to the minimum strength of four operational satellites.

A navigation receiver generally needs signals from at least four satellites to determine its precise three-dimensional position and correct the timing error in its internal clock. Three satellites can theoretically determine a position if the receiver already knows its altitude, but ordinary phones, vehicles and navigation devices do not carry the highly accurate atomic clocks needed to eliminate clock-error calculations.

NavIC provides two services. The Standard Positioning Service is available for civilian users, while the encrypted Restricted Service is reserved for authorised strategic users, including the armed forces and security agencies.

The system is designed to cover India and an area extending up to 1,500 km beyond the country’s borders. Its signals are provided in the L5 and S bands.

For India’s security forces, an operational NavIC would strengthen strategic autonomy by reducing dependence on foreign-operated navigation networks such as the US Global Positioning System (GPS).

Foreign navigation services can theoretically be restricted, degraded, denied or selectively prioritised during a conflict. India’s experience during the 1999 Kargil War reinforced concerns about dependence on systems controlled by other countries.

An indigenous positioning, navigation and timing network is particularly important for ballistic missiles, precision-guided munitions, military aircraft, naval vessels and encrypted operational networks. Reliable PNT data supports accurate targeting, movement, coordination and timing across these systems.

NavIC would therefore provide the armed forces with a secure alternative for navigation and targeting data, while helping maintain operational capability during geopolitical crises or a military confrontation.

Union Minister of State for Space Jitendra Singh informed the Lok Sabha in July that NVS-03 was ready for launch, while NVS-04 and NVS-05 were at an advanced stage of realisation. Another satellite is planned thereafter to help rebuild the seven-satellite base-layer constellation.

The October mission is consequently important not only for restoring NavIC’s immediate positioning service, but also for rebuilding confidence in India’s indigenous satellite-navigation architecture after the NVS-02 setback.

Agencies