On this India Today special report, Akshita Nandagopal examines the recent failure of ISRO's PSLV-C62 mission launched from Sriharikota. The bulletin highlights that while the first two stages were successful, a critical pressure drop in the third stage led to 'disturbances in the roll' and a subsequent loss of trajectory. Akshita Nandagopal notes that this follows a similar pattern seen in the PSLV-C61 launch in May 2025. The mission was carrying a DRDO maritime surveillance satellite and 15 co-passenger satellites. Shibu Tripathi, Senior Assistant Editor, joins the discussion to explain that while most payloads were lost, a reentry capsule from a Spanish startup reportedly survived. Despite the setback, the PSLV remains ISRO's workhorse, though back-to-back failures in the third stage have raised concerns regarding manufacturing inconsistencies or micro defects. ISRO is expected to form a committee to investigate the exact cause of the combustion instability.
00:00The unfortunate development yesterday is that Shriharikota, when ISTRO attempted a launch of the PSLV C-62, it failed.
00:08And that setback has brought gloom clouds among Indian space enthusiasts.
00:12But what exactly happened?
00:14What led to that mission failure, which hasn't been deemed officially a failure, by the way, by ISTRO?
00:20I'll break it down for you.
00:22What happened?
00:23Because we saw a successful launch, but it's in the third stage that things went wrong.
00:27The third stage boosts the rocket speed from 14,000 to 26,000 to 28,000 kilometers per hour, which essentially keeps it flying horizontally.
00:37So essentially, this is the Earth's surface.
00:39It will be flying like this.
00:40Now, to avoid it, to falling back on Earth, it has to go horizontal.
00:44And so it also positions it for the final stage.
00:47There's no margin for error here.
00:49It has to follow the specified trajectory.
00:51And a failure here can doom the entire mission, no matter how successful the earlier stages were,
00:56which is what happened in this particular case.
00:58First stage successful, second stage successful, a problem in the third.
01:02But what's happening?
01:03Why is it failing?
01:05The combustion instability can cause a sudden drop in chamber pressure because this is a solid motor.
01:11It can be throttled.
01:12It can be restarted.
01:14ISTRO scientists have said that the suspected reasons, they don't know exactly what it is,
01:18but they suspect it could be a micro defect or even manufacturing inconsistencies.
01:23They're yet to figure it out.
01:24Usually, there's a committee that's set up that looks into what happened.
01:27But in this case, there's a chain reaction of sorts.
01:30The moment the pressure drops, it leads to roll disturbances.
01:34And so it doesn't follow the planned trajectory.
01:36It moves off course.
01:38And so loss of payloads.
01:40In this case, almost 16 satellites.
01:43This isn't, unfortunately, the first time it's happened, which is why there's so much of concern.
01:47The same thing happened last year when there was again a PSLV failure launch.
01:52This was the C61 in 2025, which failed to reach orbital velocity due to a pressure drop in the third stage.
02:00PSLV C62 yesterday again showed a similar pattern.
02:04Third stage, possibly you also see a trajectory deviation.
02:08And that led to an uncontrolled spin.
02:10The common factor between these two failures show the inability to deliver consistent thrust due to pressure anomalies.
02:17This isn't new.
02:19In 1993, PSLV D1 failed at stage 2-3 separation.
02:24In 2017, PSLV C39 failing during payload fairing.
02:28The third stage has essentially emerged repeatedly as the weak link in the PSLV family.
02:34And now, unfortunately, to add to the track record, you have C61, C62, which have proved, again, that decades of experience cannot completely eliminate risk at the critical stage.
02:46ISRO, at this point, hasn't issued any statements on exactly what's gone wrong.
02:50They're still looking into it.
02:52But, important to highlight here, I was talking about 16 satellites.
02:56One of them, a Spanish startup or orbital paradigm, revealed that its satellite has survived what's happened, the trajectory deviation, and that it's very much functioning.
03:08Does this mean ISRO has had a string of failures?
03:10100% no.
03:12PSLV is still Mr. Reliable for ISRO.
03:14But the fact that there have been two back-to-back such incidents is what has raised questions and led to some discourse on whether we need to look at what's gone wrong.
03:23I'll bring in Shibu Tripathi, senior assistant editor of Science, who tracks the space sector very, very closely for us.
03:30Shibu, what surprised me through the course of all that's happened and that in the last 24 hours is that there doesn't seem to be any concrete reasons given by ISRO, or for that matter, status report of what happened.
03:41Akshita, definitely, this is one of the most concerning events that has happened in the last 24 to 48 hours.
03:47This was the second loss of a PSLV class of rocket for India, along with multiple satellites.
03:53Now, this mission, the PSLV C-62, was highly important for India.
03:57India was launching a DRDO satellite which was required for maritime surveillance.
04:02It was being used for defense services for disaster relief and rehabilitation work.
04:06Apart from that, 15 other co-passenger satellites were on it.
04:10The PSLV C-61, which was launched in May 2025, suffered a similar fate.
04:14We saw that there was issue with the third stage of the rocket.
04:18This is a four-stage rocket, the PSLV.
04:20It has been a workhorse in the past.
04:22It still continues to be a workhorse in the future.
04:25And going forward, it looks interesting because ISRO now will have to find out what really went wrong with the rocket.
04:32Surprisingly, there has been no development so far from ISRO at the moment.
04:36They have not told us the exact reasons of what happened.
04:38The only information we got during the live stream was from the ISRO chief, Dr. V. Narayanan,
04:44that there were disturbances in the role due to drop in pressure, which eventually led to the complete loss of mission.
04:51At the moment, the latest information that we have is one of the satellites, as you mentioned, survived that fiery re-entry.
04:58Correct.
04:58So, orbital paradigms, KID.
05:01Now, interestingly, this was a capsule that was designed to test re-entry.
05:06So, had the entire fourth stage come down, it would have come down with it intact.
05:10The latest information also points that the debris might have fallen into the southern Indian Ocean, Akshita.
05:16All right. Thanks, Shibu, for getting us those updates.
05:19We're waiting for a statement from ISRO, and let's hope they go back to their record streaks of non-stop successful launches very, very soon.
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