ISRO Tests Gaganyaan Propulsion Module

On July 3, 2025, the Indian Space Research Organisation (ISRO) achieved a major milestone by successfully testing the Gaganyaan propulsion system at the ISRO Propulsion Complex in Mahendragiri, Tamil Nadu.

This test marks a pivotal step toward launching India’s first crewed space mission under the prestigious Gaganyaan Programme.

The Gaganyaan propulsion system is central to the mission's success, enabling critical orbital maneuvers, trajectory correction, and emergency aborts to ensure crew safety.

What Is the Gaganyaan Propulsion System?

The Gaganyaan propulsion system, officially called the Service Module Propulsion System (SMPS), is a vital subsystem of the Gaganyaan Orbital Module.

Key Functions:

• Executes orbital maneuvers

• Provides trajectory adjustments

• Enables emergency abort sequences

Core Components of the Gaganyaan Propulsion System:

• 5 Liquid Apogee Motors (LAM engines) with 440 Newton thrust each

• 16 Reaction Control System (RCS thrusters) with 100 Newton thrust each

• Capable of functioning in both steady-state and pulsed modes

The Gaganyaan propulsion system plays a crucial role not just in navigation but in ensuring mission success and astronaut safety.

ISRO Engine Test – July 3, 2025: Hot Fire Trials

ISRO conducted two fire tests of the Gaganyaan propulsion system to simulate space-like conditions:

• 30-second short-duration test

• 100-second extended-duration test

These tests evaluated the complete configuration of the Gaganyaan propulsion system, verifying the seamless operation of both LAM thrusters and RCS systems under extreme performance conditions.

Significance of the 100-Second Test

The 100-second test was a landmark demonstration of the Gaganyaan propulsion system’s capacity to perform real-time operations during a crewed mission.

Key Achievements:

• Simultaneous firing of all RCS thrusters in both operational modes

• Full-scale operation of all LAM engines

• Accurate simulation of in-orbit maneuvering

The Gaganyaan propulsion system proved its robustness under simulated flight conditions, validating its readiness for upcoming crewed missions.

ISRO’s Liquid Propulsion Systems Centre (LPSC)

The Gaganyaan propulsion system is being developed by ISRO’s Liquid Propulsion Systems Centre (LPSC). Continuous design improvements have been made to ensure the system’s suitability for actual space conditions.

Enhancements made for the latest test include:

• Increased structural fidelity with flight models

• Optimized firing sequences for LAM and RCS

• Better synchronization with crew safety protocols

The upgraded Gaganyaan propulsion system reflects ISRO’s commitment to precision and safety in human spaceflight.

Why the Gaganyaan Propulsion System Is Critical

A successful Gaganyaan propulsion system ensures:

• Reliable trajectory correction

• Efficient orbital placement

• Life-saving abort operations if needed

The system integrates both LAM engines (for main thrust) and RCS thrusters (for fine adjustments and attitude control), making it central to Gaganyaan’s crew safety system.

The difference between LAM and RCS in Gaganyaan highlights their complementary roles in maneuvering and emergency response.

Quick Facts for Competitive Exams

Sample MCQs:

• What is the purpose of Gaganyaan reaction control thrusters?

• How does the Gaganyaan propulsion system work during in-orbit operations?

• What is the difference between LAM and RCS in Gaganyaan?

Strategic Importance: India’s Future in Space

The successful testing of the Gaganyaan propulsion system reinforces ISRO’s technological leadership. It also sets the stage for future missions involving space exploration, interplanetary travel, and human colonization efforts.

India now stands alongside elite spacefaring nations by demonstrating an advanced, crew-safe propulsion module.

Final Thoughts

The Gaganyaan propulsion system has passed a major trial with flying colors. The ISRO engine test (July 2025) demonstrates the system’s readiness to power India's first human space mission, with safety, precision, and national pride.

With further qualification tests on the horizon, the Gaganyaan service module is gearing up to take Indian astronauts to low Earth orbit and back safely. The success of this ISRO propulsion module not only advances science but also boosts India's global standing in space technology and engineering.