4 months ago
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The communicative truthful far:
On January 12, the Indian Space Research Organisation’s (ISRO) PSLV-C62 ngo lifted disconnected from Sriharikota carrying the EOS-N1 outer on with 15 co-passenger satellites. Within minutes, ISRO said the ngo had “encountered an anomaly during extremity of the PS3 stage”, and that a elaborate investigation was initiated.
What was the anomaly?
In a televised briefing aft the launch, ISRO chairman V. Narayanan described what ngo power was seeing: that show was “as expected” up to adjacent the extremity of the rocket’s 3rd stage, called PS3, past that determination was accrued “disturbance successful the conveyance rotation rates”, followed by a deviation successful the formation path. In different words, towards the extremity of the 3rd stage, the rocket was spinning uncontrollably, capable for it to not beryllium capable to proceed connected its planned path. As of January 16, ISRO hasn’t published a connection astir the basal origin of the mishap.
Following the incident, Thailand’s abstraction agency GISTDA, whose THEOS-2A outer was connected board PSLV-C62, said a malfunction precocious successful the 3rd signifier caused an attitude-control abnormality and the conveyance deviated from its trajectory, preventing the rocket from deploying the satellites it was carrying. GISTDA also said the rocket and satellites were expected to autumn backmost and pain up implicit the confederate Indian Ocean. The anomaly resembled the events preceding the nonaccomplishment of the PSLV-C61 ngo connected May 18, 2025.
What happened to PSLV-C61?
ISRO’s PSLV-C61 ngo was carrying the EOS-09 satellite. The rocket failed aft the archetypal 2 stages, with the 3rd signifier not performing nominally. ISRO noted a driblet successful enclosure unit successful the third-stage centrifugal lawsuit during the PS3 operation, aft which it said the ngo “could not beryllium accomplished”.
Based connected what has been reported publically truthful far, some the C62 and the C61 missions suffered decisive anomalies connected PS3 aft a nominal aboriginal ascent and neither could deploy their payloads into the designated orbit (with a qualification for the KID payload). In C62, the main grounds was a “roll complaint disturbance” precocious successful the PS3 signifier operation; successful C61, the grounds was a chamber-pressure driblet successful the PS3 centrifugal casing.
ISRO’s initial communications successful some cases besides stressed that an anomaly had occurred and that investigation was underway, but it did not people a elaborate database of corrective actions it would person to take. After the C61 ngo failed, Dr. Narayanan constituted a Failure Analysis Committee (FAC) to look into the causes of the mishap. The FAC submitted its study to the Prime Minister’s Office successful mid-2025.
What does the FAC do?
The FAC is not a lasting assemblage of experts within ISRO but alternatively an entity the ISRO chairman constitutes successful the lawsuit of a large incident. Its work is to reconstruct the concatenation of events starring up to the nonaccomplishment utilizing telemetry and subsystem information and successful speech with radical progressive successful that mission. It’s expected to place the causes, and urge corrective enactment earlier the conveyance is cleared for a ‘return to flight’.
The Committee members see experts within ISRO as good arsenic applicable experts from academia. It has besides been known to see former ISRO chairmen. The FAC submits its last study to the Indian government. The ISRO chairman is Secretary to the Department of Space, which functions straight nether the PMO.
The aftermath of the GSLV-F10 ngo provides an instructive model into the FAC’s efforts. After that ngo failed successful 2021, here’s an excerpt of what the FAC found: “The FAC concluded that the little liquid hydrogen vessel unit astatine the clip of cryogenic precocious signifier motor ignition, caused by the leakage of vent and alleviation valve resulted successful the malfunctioning of the substance booster turbo pump, starring to ngo abort bid and consequent nonaccomplishment of the mission.”
Where is the PSLV-C61 FAC report?
Although the PSLV-C61 FAC submitted its study to the PMO, the PMO hasn’t cleared it for nationalist merchandise yet. Independent experts criticised the determination to withhold it after PSLV-C62 besides suffered an anomaly successful its 3rd stage. ISRO has besides not said whether it has constituted an FAC for the C62 mission, though a abbreviated connection connected its website says “a elaborate investigation has been initiated”. On November 15, 2025, during an unrelated lecture, Vikram Sarabhai Space Centre manager A. Rajarajan had attributed the nonaccomplishment of the PSLV-C61 ngo to a “slight manufacturing error”.
That said this isn’t the archetypal clip details of the FAC’s findings of a mishap person been withheld. Previous instances see the PSLV-C39 ngo successful 2017. ISRO has besides been terse astir the issues starring up to the underperformance of the NVS-02 satellite.
Earlier, adjacent erstwhile the FAC study hadn’t been released into the nationalist domain, ISRO had issued statements with elaborate summaries of the FAC’s findings, for example, aft the GSLV-F10 ngo successful 2021 and the GSLV-F02 ngo successful 2006. The aftermath of PSLV-C61 is simply a interruption from the past successful this consciousness arsenic well, since nary specified statements person been issued.
What happened to satellites on PSLV-C62?
The mission’s superior payload was EOS-N1, a surveillance outer from the Defence Research and Development Organisation. The co-passengers comprised payloads involving Thailand, the U.K., Nepal, France, Spain, and Brazil, positive 7 satellites from Indian enterprises.
The PSLV has failed 4 times truthful far, but PSLV-C62 was the archetypal clip it failed portion carrying lawsuit satellites provided by Indian and overseas entities. The ngo had been facilitated by ISRO’s commercial arm, NewSpace India, Ltd. While the ISRO didn’t accidental whether the ngo had failed aft the anomaly connected January 12, the connection from Thailand’s GISTDA suggested that the rocket’s remaining stages and the payloads would autumn backmost down towards the world and pain up.
The KID payload was a reentry demonstrator — a instrumentality designed to autumn backmost down from orbit and splash into the confederate Pacific Ocean. In a connection released aft January 12, Orbital Paradigm, its Spain-based co-developer, said KID had transmitted “off-nominal” information for astir 3 minutes.
GISTDA said its THEOS-2A outer had been insured. The Indian backstage assemblage payloads onboard PSLV-C62 reportedly hadn’t been insured, truthful the outgo of the nonaccomplishment would person been absorbed by the developers of each satellite. The outgo of losing EOS-N1 volition beryllium borne by India.
