• ISRO completed the first Integrated Air Drop Test (IADT-01) for Gaganyaan programme at Satish Dhawan Space Centre (SDSC), Sriharikota on August 24. 

• This test successfully demonstrated the objective of end-to-end performance validation of the critical parachute-based deceleration system of the Crew Module for Gaganyaan mission in one of the typical mission scenarios. 

• This test is part of system level qualification of parachute-based deceleration system, in which a simulated Crew Module, encompassing the deceleration system is dropped using a helicopter.

Gaganyaan Mission

• Prime Minister Narendra Modi announced the Gaganyaan mission in his Independence Day address in 2018.

• Gaganyaan project envisages demonstration of human spaceflight capability by launching a crew of three members to an orbit of 400 km for a three days mission and bring them back safely to Earth, by landing in Indian sea waters.

• For the first human spaceflight, four Indian Air Force pilots have been selected and are undergoing extensive training for the mission.

• A budget of Rs 9,023 crore is allocated towards achieving the objectives of the mission.

• ISRO developed indigenous technologies for the launch vehicle, habitable Crew Module, life support system, Crew Escape System, ground station network, crew training and recovery.

• These technologies are crucial to meet the objectives of Gaganyaan mission and to take up any further interplanetary missions.

• Gaganyaan will not be a one-off mission as the government has given approval for a sustained human spaceflight programme.

• The programme comprises three uncrewed missions and one crewed mission.

• The maiden Gaganyaan uncrewed mission is expected to be launched in December 2025 with a humanoid robot, Vyommitra.

How was the Integrated Air Drop Test conducted?

• In Gaganyaan missions, a parachute-based deceleration system is employed during the terminal phase of Crew Module descent to reduce the touchdown velocity to an acceptable limit for safe landing on sea. 

• The parachute system tested was the same as that of Gaganyaan missions and comprised ten parachutes — two Apex Cover Separation (ACS), two drogue, three pilot and three main canopies.

• The 4.8-tonne simulated Crew Module was released from about 3 km altitude using the Indian Air Force’s Chinook heavy-lift helicopter. 

• The deceleration system initiation began with firing of ACS Mortar, which deploys the 2.5 m ACS parachutes, which is followed by the separation of apex cover.

• Drogue parachutes provided the first stage of deceleration, before being released to allow three pilot parachutes to deploy the three main parachutes of 25 metres diameter.

• Further, main parachutes reduced the terminal velocity of the simulated Crew Module to about 8m/s. 

• After touchdown, the main parachutes were released using parachute releasers. 

• These parachutes, totalling 10 in number, deployed in a precise sequence to gradually decrease the velocity of the Crew Module for safe touchdown.

• The test simulated a possible abort scenario on the launch pad, with onboard avionics commanding the deceleration sequence and telemetering data to ground.

• Post splashdown, the simulated Crew Module was successfully recovered and ferried back on INS Anvesha to Chennai port.

(The author is a trainer for Civil Services aspirants.)