'There's too much coincidence in back-to-back failures of missions critical to national security.'
India's space programme suffered a major setback on Sunday, May 18, 2025, as the Polar Satellite Launch Vehicle-XL (PSLV-XL) mission failed mid-flight, resulting in a loss of approximately ₹850 crore (Rs 8 billion).
The mission, designated PSLV-C61, was intended to deploy the Earth Observation Satellite EOS-09, a key surveillance asset with strategic importance.
This was the 101st launch from ISRO's spaceport at Sriharikota.
EOS-09, equipped with a synthetic aperture radar (SAR), was designed to strengthen India's surveillance capabilities, similar in function to EOS-04 launched in 2022. The 1,696.24 kg satellite had an expected mission life of five years.
The PSLV-XL rocket, standing 44.5 metres tall and weighing 321 tons, lifted off at 5:59 am IST. About six minutes into the flight, soon after ignition of the third stage powered by solid fuel, the rocket veered off course. Visuals from the Mission Control Centre confirmed the deviation.
ISRO Chairman V Narayanan stated that while the first two stages functioned nominally, the third stage experienced a drop in chamber pressure, leading to mission failure. 'There was an observation in the third stage,' he said, without elaborating further.
ISRO later tweeted: 'Today's 101st launch was attempted. PSLV-C61 performance was normal till the 2nd stage. Due to an observation in the 3rd stage, the mission could not be accomplished.'
This failure marks the second consecutive loss of a mission with strategic implications.
In January 2025, the ₹300 crore (Rs 3 billion) GSLV mission carrying the NVS-02 navigation satellite failed to reach its intended orbit due to a pyro valve malfunction.
The valve failed to open, preventing oxidizer flow despite the fuel pumps functioning properly.
A retired senior ISRO official suggested the PSLV-C61 third stage issue could stem from a faulty valve or electrical connector, leading to the pressure drop.
"There's too much coincidence in back-to-back failures of missions critical to national security," he said.
The NVS-02 was supposed to replace the ageing IRNSS-1E satellite, part of India's regional navigation system.
Despite having full redundancy in valves and electronics, experts suspect a failure in power supply to the valve, potentially due to an unconnected power line after final testing.
It remains unclear whether the Failure Analysis Committee report for the NVS-02 incident has been completed or made public.
The PSLV, a four-stage rocket using alternating solid and liquid fuels, has a strong success record.
Sunday's failure is only the third in its history, following failures in 1993 and on August 31, 2017.
The 2017 failure baffled ISRO when the rocket's heat shield did not separate, trapping the IRNSS-1H satellite inside.
ISRO later attributed the problem to a malfunction in the pyro separation system.
There have been earlier concerns with PSLV hardware as well. The 2010 launch of IRNSS-1A was delayed due to a faulty actuator in the second stage, and ISRO had to dismantle a fully assembled PSLV to replace a gas motor in another instance.
While the PSLV-XL failure may cause only a minor dent in ISRO's reputation in the global small- and medium-satellite launch market, the repeated failures of strategic missions are more troubling.
These not only represent financial losses but also missed opportunities in critical national security areas.
The EOS-09 mission alone was estimated to cost ₹550 crore (₹5.5 billion) for the satellite and ₹300 crore (₹3 billion) for the rocket.
With growing international competition in space and increasing reliance on space-based intelligence and navigation, ISRO must now urgently address these recurring failures--especially in missions tied to India's strategic interests.
Venkatachari Jagannathan can be reached at venkatacharijagannathan@gmail.com
Feature Presentation: Rajesh Alva/Rediff
© 2025