Experts from Intelegrid, Thiruvananthapuram, a firm specialising in the cyber-physical security of critical infrastructure, on Monday called for a comprehensive forensic review of ground-station and antenna systems following the third-stage anomaly in ISRO’s PSLV-C62 mission.

The experts said the recurrence of similar third-stage deviations in recent PSLV flights raises concerns about a possible emerging pattern rather than an isolated technical failure.

ISRO has confirmed that the PSLV-C62 launch experienced a deviation during the third stage of flight, which ultimately prevented the successful insertion of the payload into its intended orbit.

While the national space agency has initiated a detailed technical investigation into the anomaly, Intelegrid experts pointed out that another recent PSLV mission had also reported a guided-phase anomaly, indicating that the issue may no longer be viewed purely as a one-off malfunction.

“The back-to-back occurrence of third-stage deviations suggests the possibility of a repeatable failure mode rather than unrelated faults,” an Intelegrid spokesperson said.

“That makes it essential to examine not only onboard hardware and propulsion systems but also the ground-segment command, navigation, and telemetry systems that guide the vehicle during powered flight.”

The firm explained that during the third stage of flight, PSLV relies on a fusion of inertial sensors and satellite-based navigation inputs to maintain its trajectory, while mission control sustains telemetry downlinks and limited command uplinks through ground antennas.

Any disruption, delay, or distortion in this data chain, including issues related to antenna performance, timing accuracy, or command-generation systems, could affect the launch vehicle’s trajectory even if the propulsion systems themselves function normally.

Intelegrid further pointed to the growing global use of GPS and navigation spoofing techniques in electronic and cyber warfare, warning that corrupted navigation or timing data can mislead onboard guidance computers.

Such interference, the experts said, can produce precisely the kind of trajectory deviation observed during the third stage of the PSLV-C62 mission.

The experts recommended that ISRO’s post-flight analysis should include a thorough verification of antenna and uplink logs, command authentication records, GNSS reference data and timing sources, as well as detailed consistency checks between telemetry received on the ground and the onboard flight memory.

These steps, they said, are necessary to conclusively rule out any data-integrity, signal-interference, or cyber-related issues affecting the mission.

ISRO, however, has not suggested any possibility of external interference and has stated that it is closely analysing all available flight data to determine the precise cause of the third-stage anomaly encountered during the PSLV-C62 mission.