India’s ambitious Gaganyaan Mission achieved a significant milestone as the Indian Space Research Organisation (ISRO) successfully conducted its first Integrated Air Drop Test (IADT-01) at the Satish Dhawan Space Centre (SDSC), Sriharikota. This critical test validated the end-to-end performance of the parachute-based deceleration system—a key component that ensures the safe return of astronauts to Earth.

Purpose of the Test

In the Gaganyaan mission, the Crew Module (CM)—which will eventually carry astronauts—is designed to safely descend and land in the sea after re-entry. To achieve this, ISRO employs a multi-layered parachute-based deceleration system that gradually reduces the module’s speed during its terminal phase.

The IADT-01 was conducted to simulate one of the mission scenarios and validate how the parachutes deploy in sequence to achieve a safe splashdown.

Parachute Configuration

The deceleration system tested in IADT-01 was identical to what will be used in the actual Gaganyaan mission. It consisted of 10 parachutes deployed in a precise order:

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Apx Coever Separation (ACS) Parachutes – 2 units (Ø 2.5 m each)

Drogue Parachutes – 2 units (Ø 5.8 m each)

Pilot Parachutes – 3 units (Ø 3.4 m each)

Main Parachutes – 3 units (Ø 25 m each)

This layered system ensures progressive reduction of speed for maximum safety.

Test Execution

A simulated Crew Module weighing ~4.8 tonnes was carried to an altitude of about 3 km by the Indian Air Force’s Chinook Heavy-Lift Helicopter.

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The test began with the firing of ACS mortars, deploying the 2.5 m ACS parachutes that separated the apex cover while preventing re-contact with the module.

Next, drogue parachutes were deployed, providing the first stage of deceleration.

The drogues were then released using pyro-based parachute releasers, followed by the deployment of pilot parachutes, which in turn extracted the three main parachutes.

Finally, the massive 25 m main parachutes reduced the crew module’s terminal velocity to about 8 m/s, ensuring a safe and controlled touchdown.

After splashdown, the module was recovered by INS Anvesha and transported to Chennai Port.

Abort Scenario Simulation

The IADT also tested an abort scenario, simulating a case where the crew module needs to separate from the rocket on the launch pad. The onboard avionics automatically triggered the parachute deployment in the correct sequence. Data was collected through:

Onboard avionics systems

Solid State Data Recorder (SSDR)

Telemetry systems transmitting real-time data to ground stations

Preparations Before the Test

Before the final air-drop, ISRO conducted extensive simulations and trial runs:

Detailed modeling of both the crew module and helicopter dynamics.

Dummy module drops with IAF’s Chinook helicopters.

Mission rehearsals to finalize the Standard Operating Procedures (SOPs).

Final clearance from the Test Authorisation Board (TAB) before IADT-01 execution.

Collaborative Effort

The successful IADT was not just ISRO’s achievement but a multi-agency collaboration. Contributions came from:

Defence Research and Development Organisation (DRDO)

Indian Air Force (IAF)

Indian Navy

Indian Coast Guard

Their joint support ensured the mission test met international safety and operational standards.

What’s Next?

ISRO has confirmed that more such tests will follow, covering different altitudes, velocities, and deployment scenarios. These trials are essential to ensure crew safety before India’s first human spaceflight mission under Gaganyaan takes off.

Conclusion

The successful Integrated Air Drop Test marks a giant leap forward for India’s human spaceflight ambitions. By validating the parachute deceleration system, ISRO has taken a crucial step toward ensuring astronaut safety in the Gaganyaan mission. With multiple upcoming qualification tests, India is steadily moving closer to launching its first crewed space mission, a historic milestone in its space exploration journey.