By A Correspondent

Bengaluru: In a significant technological breakthrough for India’s maiden human spaceflight programme, Indian Space Research Organisation (ISRO) has completed the development and qualification of the Service Module Propulsion System (SMPS) for the ambitious Gaganyaan mission. The latest achievement marks a critical step forward in ensuring astronaut safety and mission readiness.

The final and most crucial full-duration hot test of the SMPS was conducted on July 11, lasting 350 seconds. It was designed to simulate an off-nominal mission scenario involving a service module-based mission abort. According to ISRO, the propulsion system performed flawlessly and as predicted, validating its readiness for the next phase of human spaceflight.

“The test validated the propulsion system’s integrated performance for a mission abort scenario. The system performed normally, as predicted,” ISRO said in a statement.

What is the SMPS and Why It Matters

The Service Module Propulsion System is a vital component of the Gaganyaan spacecraft, providing key functions including:

• Orbit circularisation
• On-orbit control
• De-boost manoeuvres
• Abort capability during ascent

The propulsion system is powered by a regulated bi-propellant engine, with the primary thrust provided by Liquid Apogee Motors (LAMs) and precise attitude control ensured by Reaction Control System (RCS) thrusters.

This propulsion technology is mission-critical, not only for guiding the crew module through complex orbital manoeuvres but also for enabling safe escape mechanisms during potential emergencies — a core requirement for human spaceflight safety standards.

Intensive Testing for Human-Rating

To simulate and rigorously evaluate real-world mission conditions, ISRO developed a System Demonstration Model (SDM) that replicates the SMPS fluid circuit, including:

• Propellant feed lines
• Helium pressurisation system
• Flight-qualified thrusters
• Critical control components

The testbed underwent an exhaustive 25-test campaign, totaling over 14,331 seconds of firing under both nominal and off-nominal conditions. This extensive testing was crucial for fulfilling human-rating benchmarks and ensuring system reliability.

Developed by LPSC, Tested at IPRC

The Liquid Propulsion Systems Centre (LPSC) led the development of the SMPS, with all qualification and hot-fire tests conducted at ISRO’s Propulsion Complex in Mahendragiri (IPRC). The tests demonstrated not just the functional robustness of the propulsion unit but also ISRO’s capability in executing complex, safety-critical engineering required for human spaceflight.

Strategic Significance

This successful qualification of the SMPS is more than a technical feat; it represents India’s growing prowess in human-rated spaceflight systems, bringing the country one step closer to sending Indian astronauts into low Earth orbit. The Gaganyaan mission, slated for launch in the coming years, aims to establish India as the fourth nation in the world — after the US, Russia, and China — to demonstrate independent human spaceflight capability.

This development showcases ISRO’s commitment to delivering a safe, reliable, and world-class spaceflight system — a leap forward in India’s journey toward crewed space exploration.

NOTE: Follow Defence.Capital on Telegram.
NOTE: Follow Defence.Capital on WhatsApp.