 Liftoff of the TV-D1 mission October 21 to demonstrate the crew escape system for the Gaganyaan spacecraft. (credit: ISRO) |
ISRO prepares for human spaceflight
by Gurbir Singh
Monday, October 23, 2023
In 2025, India is planning its first crewed spaceflight, carrying astronauts on an Indian launch vehicle, launched from India. On October 21, ISRO conducted an uncrewed in-flight abort test. One minute into the flight, the Crew Escape System fired for just over two seconds, pulling the crew module away from the launch vehicle. The momentum took the crew module to an altitude of 17 kilometers, where the Crew Escape System itself separated from the crew module. Neither the launch vehicle nor the Crew Escape System were recovered. The crew module descended to a safe splashdown ten kilometers downrange, first using a pair of drogue parachutes and then three main parachutes. About nine minutes after launch the mission concluded having met all the mission objectives successfully.
| Since Yuri Gagarin’s first human spaceflight in 1961, launch escape systems have been activated in three instances and saved the lives of the crew in each case. |
ISRO concluded this in-flight abort test a complete success despite the poor weather that obscured the launch and the descent. Infrared cameras and the telemetry provided ISRO with the data it required. The ISRO chairman explained that the unexpected hold at T-5 seconds during the first launch attempt was due to the automatic launch sequence detecting a weather threshold breach. The rescheduled launch attempt 45 minutes later was successfully completed despite the crew capsule initially floating upside down. This is not an unexpected outcome for NASA, as the Apollo 11 crew capsule was discovered just after splashdown in July 1969. NASA referred to this position as “Stable 2”.
In emergencies, ships have lifeboats and aircraft have inflatable evacuation slides. Most crewed launch vehicles heading for space have launch abort or escape systems. They can be activated on the launchpad before launch or soon after launch. Like an ejection seat used by a fighter pilot in an emergency, small but fast-acting solid motors separate the crew module from the rest of the launch vehicle for a safe evacuation. Since Yuri Gagarin’s first human spaceflight in 1961, launch escape systems have been activated in three instances and saved the lives of the crew in each case.
In April 1984, Rakesh Sharma, India's first astronaut, spent a week on board Salyut 7 as part of the USSR's Interkosmos program. Six months earlier, on September 26, 1983, flight engineer Gennady Strekalov and his commander Vladimir Titov survived the fire that broke out moments before the launch of Soyuz T-10-1. The crew escape system fired, separating the crew module from the inferno that engulfed the launch vehicle seconds later. The crew module landed safely four kilometers away. The commander and engineer were bruised and shaken but fully recovered, aided by cigarettes and vodka.
Both Rakesh Sharma and Ravish Malhotra watched this drama unfold in real time, as the next Soyuz flight would be theirs. On April 2, 1984, Gennady Strekalov and Rakesh Sharma were part of the crew launched on the successful Soyuz T-11 mission to Salyut 7. Sharma and Malhotra had been in training in Star City since September 1982. Both were Indian Air Force test pilots and familiar with high-risk missions. Sharma recalled he did not tell his wife about witnessing this launch failure “as had been my practice right through my flying and testing career.”
Soyuz-T-10 was the second use of a launch abort system, the first took place during the Soyuz 7K-T No.39 mission almost a decade earlier. It was taking a crew of two to the Salyut 4 space station on April 5, 1975. About five minutes after launch, separation between stage two and stage three did not go as planned, compromising the mission. The Soyuz activated the escape system separating the crew module from the launch vehicle. Twenty minutes after launch the crew landed safely in the USSR on a snow-covered hillside close to the Chinese border. Thinking they may have landed in China, the crew destroyed sensitive documents associated with the military experiments they intended to conduct in orbit. Thanks to their survival suits and training, they endured the freezing temperature overnight and were recovered on the following day.
The third incident took place on October 11, 2018, when Soyuz MS-10 experienced a booster separation issue a few minutes after launch. This meant NASA astronaut Nick Hague and Russian cosmonaut Aleksey Ovchinin would not reach their destination, the International Space Station. The Soyuz initiated the abort, separating the crew module from the launch vehicle and landed safely about 20 minutes after launch. Despite experiencing a force of around 7 g’s, both crew members were safely recovered in good health and returned to Baikonur. Soyuz MS-12 launched in March 2019 and successfully completed the mission objectives originally planned for the MS-10 mission.
| It may well be that the next Indian astronaut to fly in space will be on the ISS, before Gaganyaan. |
Developing and testing Gaganyaan’s Crew Escape System is one of the many prerequisite critical systems ISRO must develop and demonstrate prior to the first crewed flight. India's human spaceflight program has had a checkered history. The first public report of India's intention to develop a human spaceflight program came in 2007. The program was formalized and announced in 2009 but not really funded. At that time, the close relationship between ISRO and Roscosmos was expected to deliver results by 2016. That timeline did not materialize but ISRO has been quietly developing many of the critical systems required for the Gaganyaan program since. The formal political announcement came from the prime minister on India’s independence day, August 12, 2018. The goal then was the first crewed flight in 2022 to mark India’s 75th year of independence. Many delays, including from Covid, have shifted the first launch to at least 2025. In the meantime, ISRO has been developing critical technologies including environmental control systems, prototypes of spacesuits, and human-rating the LVM3. It has also conducted a drop test of the crew module from a helicopter and the recovery procedure after splashdown.
On July 5, 2018, ISRO conducted a pad abort test. Whilst stationary at the launch pad, the crew module was pulled away to an altitude of about three kilometers and safely splashed down less than five minutes later in the Bay of Bengal. ISRO has also conducted two flights that have involved recovering a spacecraft ISRO has launched. During a short 20-minute suborbital flight on December 18, 2014, ISRO conducted the Crew Module Atmospheric Re-entry Experiment (LVM3-X/CARE). This was an experimental suborbital flight powered only by the first and second stages of an LVM3. In January 2007, ISRO launched the Space Recovery Experiment. After 12 days in orbit, the SRE-1 was commanded to reenter allowing ISRO to test procedures for de-orbit, navigation, guidance, thermal protection, parachutes, and recovery from a predesignated point in the Indian Ocean. That 2007 recovered module is now in an ISRO museum.
ISRO tends to avoid launches in October when the monsoon season is still active. The poor visibility, the unexpected hold during the first launch attempt, the recovery of the capsule by the Indian Navy from an initial “stable 2” position all made a positive contribution to this rehearsal towards an actual crewed mission. In June 2023, India signed NASA’s Artemis Accords. It included a potential flight of an Indian astronaut to the ISS in 2024. It is unlikely but, if that happens, the astronaut selected will be one of four Indian Air Force test pilots already trained in Star City in preparation for the Gaganyaan mission. So, it may well be that the next Indian astronaut to fly in space will be on the ISS, before Gaganyaan.
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