The success of the Chandrayaan-3 mission to the Moon has increased the expectations from ISRO. The Gaganyaan programme by ISRO will allow humans to access space on local hardware, throwing open the gates to space and paving the way for missions beyond Earth orbit, as well as India's own space station. ISRO however, is committed to thoroughly testing the brand new hardware before the first crewed mission.

One question that ISRO personnel are asked all the time is when India will send humans into space. ISRO is working towards the goal with the ambitious Gaganyaan program, which will not only allow the space agency to develop the capabilities of ferrying humans to Earth orbit, but will do so on hardware that is locally designed and produced in India. ISRO has an extremely reliable rocket fleet, and the reason that the performance on the flights are normal, is because of extensive on-ground testing and developmental flights ahead of the mission.


The brand new hardware that ISRO is developing for the Gaganyaan program has already undergone an extensive battery of testing. A higher thrust was necessary from the LVM3 launch vehicle, with the rocket engines modified accordingly and tested. All the stages of the rocket have been extensively tested on the ground to ensure their performance for a human-rated mission. With Indian astronauts on board the rocket, ensuring the safety of the crew is absolutely critical.

In case the rocket veers off course or in the event of a flight that is not nominal, then ISRO needs to eject the crew module (CM) containing the humans, and recover them safely. To jettison the CM, ISRO uses specialised crew escape system (CES) motors. As the rocket engines perform differently at various altitudes because of atmospheric conditions, there is a low-altitude escape motor (LEM) as well as a high-altitude escape motor (HEM), along with a CES jettisoning motor (CJM). ISRO has already completed testing all of these components.





ISRO has procured a number of simulated crew modules, which are mock-ups with the same dimensions, weight and attachments as the CM that ISRO is expected to use on the first crewed flight. These are unpressurised crew modules, while the CM used in the final flight will be pressurised, that is isolated from the environment with a life support system carefully regulating the air inside the CM. The on-board propulsion system of the CM, to change its orientation, as well as the sequence of parachutes necessary to allow the CM to safely descend, have also been tested.

The tests in preparation for the eventual Gaganyaan mission have been proceeding for over a decade now. The most well-known of the early tests towards the program was the Crew module Atmospheric Re-entry Experiment (CARE) mission conducted in December 2014, which was followed by a pad abort test in 2018. The hot tests for the propulsion system on the CM was conducted in August 2021. Qualification tests for the human-rated cryogenic engine were completed in January 2022. A parachute air-drop test was conducted in November 2022.

The testing campaign in 2023 got more intensive, with the parachutes tested on a sled on rails, powered by rockets, in March. The thrusters on the CM were tested in April 2023, with the test campaign for the human-rated Vikas engines also completed in the same month. The on-board propulsion system of the CM was qualified in May 2023. In August 2023, there was a rocket sled test of the drogue parachute system, which pulls out the primary parachutes. In September 2023, hot tests were conducted for the upgraded CE20 engine.

During all this time, ISRO has also been training astronaut designates drawn from the Indian Air Force (IAF) using new facilities set up in Bengaluru specifically for that purpose. The training program has a syllabus designed by ISRO, DRDO and IAF, guided by Wg Cdr (Retd) Rakesh Sharma and Air Cmde (Retd) Ravish Malhotra, both of whom received training from the Soviet INTERCOSMOS program. ISRO has also started trials for the recovery operations, to bring back the CM to the ground after an ocean splashdown, which is being led by the Indian Navy.

ISRO Is Committed To Testing The Brand New Hardware Before The First Crewed Gaganyaan Flight

Now ISRO is ready to begin a series of uncrewed flights for the Gaganyaan program. The first of these is scheduled to take place on October 21, using a specially modified single-stage rocket. The flight will be used to simulate a failure condition during the launch, and ensure that the CM can eject and safely return the astronauts on board to the Earth, with an ocean splashdown. During the Flight Test Vehicle Abort Mission-1 (TV-D1), the simulated abort will take place at an altitude of 17 kilometres, at Mach 1.2, during a flight that will match the trajectory of the planned Gaganyaan flights.

After the TV-D1 mission, ISRO will conduct three additional demonstration flights, numbered D2 through D4, to qualify various systems and subsystems on the brand new hardware, ahead of the first crewed flight. While other space agencies used dogs, monkeys and chimpanzees to evaluate the impact of spaceflight on humans, ISRO is opting for the much more humane approach of using a gynoid loaded with sensors, known as Vyommitra. A mock-up crew module will also be used on an air drop test, where it will be dropped from an IAF helicopter.

The remaining milestones for the Gaganyaan program before the first crewed flight are a series of integrated air drop tests, the four demonstration flights for the test vehicle, the pad abort tests, and a series of uncrewed flights, where the entire sequence from launch, to orbital insertion, to ocean splashdown, and recovery will be rehearsed. It is only after ISRO can absolutely ensure the safety of the personnel on board, will the first crewed Gaganyaan flight take place.