Gaganyaan: From astronauts’ training to tech upgrade, ISRO making leaps to meet 2025 target for manned mission

The theoretical courses trained them in the basics of spaceflight, propulsion, aerodynamics, and details of the launch vehicle and spacecraft. The practical training included flying practice, aero-medical training, yoga, and virtual reality training focused on familiarising the crew to the hardware and interiors of the crew module and operating it during the mission.

Minister of State for Space Jitendra Singh had earlier said that the space agency will undertake two test vehicle missions to demonstrate crew escape systems mid-flight and the retrieval of the crew module once it splashed down in the ocean. This will be followed by the first unmanned Gaganyaan mission that will carry an unpressurised crew module. The space agency is trying to carry out at least one unmanned mission this year depending on the performance during the test vehicle missions.

The test vehicle mission will use a single-stage rocket to take the orbital module to space and then test the crew abort and escape parachute systems, the deceleration and splashdown of the spacecraft, systems to keep the spacecraft upright after splashdown, and processes to get the astronauts out from the module.

Subsequently, there will be two more test vehicle missions to check all systems before the second unmanned flight. As of now, the final manned flight is scheduled for 2025.

Missions for the year

The ISRO report states that the space agency has planned 15 satellite and launch vehicle missions this year, including the launch of the recently operationalised small satellite launch vehicle and three space science missions.

Other than the human spaceflight, several other big ticket missions of the space agency have been on hold owing to the pandemic, including the third lunar mission, the first solar mission, and another space observatory mission.

The report states that there will be one mission of the heavy rocket LVM3, which is likely to carry on-board Chandrayaan-3. ISRO chairperson S Somanath had earlier said that Chandrayaan-3 mission is likely by mid-2023. The mission will complete the objectives of Chandrayaan-2, attempting a soft landing and then roving on the lunar surface close to the south pole of the celestial body.

The report states that high-pressure leak checks of gas bottles and propellant tanks have already been carried out. A leak in the helium gas bottle, used to pressurise the cryogenic fuel in the rocket’s upper stage, had resulted in Chandrayaan 2 mission being halted on the launch pad minutes before the launch.

According to officials, everything for Chandrayaan-3 mission is ready and the systems are undergoing final checks. “A battery of tests is being conducted to check the robustness of the systems. The systems are being tested under various simulated scenarios such as what happens if there is a dust cloud during landing, what happens if there are pebbles at the landing site.”

The Aditya L1 mission, the ISRO chairperson had previously said, is likely to take place in June or July in 2023 on board the workhorse PSLV. The report states that all payloads are at an advanced stage of development to meet the launch schedule. “Three of the payloads of the mission have already been delivered for assembly, integration and testing.”

The report states that nine missions were carried out in total during the financial year 2022-23. The previous year’s report had estimated a total of 19 missions, including one launch under the Gaganyaan mission and three space science missions, none of which happened during the year.

Gaganyaan preparedness

India’s heaviest rocket LVM3 has be human-rated for the Gaganyaan mission, meaning more redundancies and margins have to be added to ensure safety of the crew. The rocket uses two solid boosters, the core liquid fuel-based stage, and the cryogenic upper stage. The human-rated solid boosters were used during the March launch of OneWeb satellites.

Towards the qualification of the core stage, eight tests have been carried out, firing the engine for medium duration, long durations, and under conditions that are not ideal. Similarly, for the qualification of the upper cryogenic stage, eight tests have already been carried out. Three more hot tests scheduled for the second quarter of 2023 will qualify the engine as human-rated, as per the report.

With two test vehicle demonstration due before the first unmanned Gaganyaan mission, ISRO in its report said the first single-stage vehicle has already been manufactured and transported to the spaceport in Sriharikota. The launch was scheduled for the first quarter of the year. The manufacturing of the second test vehicle is also underway, the report said.

Important spacecraft systems

One of the most important systems being developed for the human spaceflight is Environment Control and Life Support System, which is tasked with maintaining pressure, temperature, humidity and gas exchange for the crew. The report says the design and configuration of several of the components of the system have been finalised. “Preliminary accommodation of the ECLSS system and half-humanoid in G1 (first unmanned mission) is completed,” the report says. ISRO will send a half-humanoid in the unmanned mission to assess likely impacts on human beings.

The space agency has also been working to qualify the parachute systems that will ensure that crew module slows down and safely splashes in the water after the mission. A ten-parachute system will be used for the crew module, with three main ones, two of which would be sufficient to bring the astronauts back safely. A total of 13 “drop tests” have been planned to test the deployment of the parachutes and simulate failure conditions, of which at least three have been completed successfully.

Other than that, various institutes have also been working on five micro-gravity experiments that will be carried onboard the uncrewed flights. This includes experiments such as how spaceflight changes in kidney stone formation in fruit fly, crystallisation of two active pharmaceutical ingredients or API with neutraceuticals in space, and instabilities in micro-gravity conditions.

Crew escape and recovery

The crew escape system for pad abort — where the mission needs to be aborted and the crew taken out safely from the rocket while on the launch pad — has already been demonstrated in 2018. The performance of the system will be demonstrated for escape of the crew while at different Mach speeds during the test vehicle missions. Static tests for the five quick acting solid motors that will be used to jettison the crew out of the main module have already been carried out, as per the report. Three sets have been manufactured to test the structure of the crew escape system.

The space agency is modifying the existing control centre to make the Gaganyaan Control Facility with a different configuration of display and consoles. An ‘umbilical tower’ – which can be used for maintenance of the launch vehicle while on the launch pad – has been created in the second launch pad and a trial for high speed bubble lift was carried out. The white room and crew access arm – from where the astronauts walk into the spacecraft – is also being developed.

Other than that the space agency is also working to create a network of ground stations that will allow direct-to-ground communication. Support for this has been finalised from European ground stations. Ship-borne terminals will also be required for telemetry, tracking and communication with the spacecraft during the ascent phase of the mission. A transportable terminal will be set up at Cocos Island, Australia, for which arrangements have been made.