ISRO aces key Air Drop Test for Gaganyaan mission

August 25, 2025

New Delhi: ISRO has successfully completed the Integrated Air Drop Test (IADT-01), a central milestone for the Gaganyaan human space mission. The test was conducted at Satish Dhawan Space Centre, SDSC, Sriharikota on Sunday, in which ISRO, Indian Air Force, DRDO, Indian Navy and Indian Coast Guard jointly participated.

Key highlights
ISRO conducted the first Integrated Air Drop Test for end-to-end demo of parachute-based deceleration system, which is required to ensure safe landing in the terminal phase of CM (Crew Module) descent for Gaganyaan missions.

Test setup
The 4.8 tonne simulated Crew Module with deployable parachute system similar to that in Gaganyaan missions was released by a Chinook heavy-lift helicopter from 3 km altitude.

Deceleration cycle
ACS parachutes deployed from ACS (Apex Cover Separation) Mortar, Apex cover separated, then Drogue parachutes gave the first deceleration step, after which Pilot parachutes deployed three Main parachutes, each Main parachute having a diameter of 25 m.

Downward velocity
The Main parachutes reduced the terminal velocity of the CM to about 8 m/s, and after touchdown the Main parachutes were disabled using releasers.

Abort scenario
The test also simulated a possible abort scenario at the launch pad, with onboard avionics commanding the deceleration sequence and sending telemetry data to the ground.

Recovery & coordination
After splashdown the simulated Crew Module was brought back to Chennai port and recovered on INS Anvesha. Extensive modelling was carried out on the dynamics of the CM and helicopter before clearance by the TAB (Test Authorisation Board).

Further steps
ISRO has said that similar tests in different deployment conditions will be conducted in the forthcoming days.