ISRO Sets New Benchmark in Space Tech with CE20 Engine Breakthrough

The Indian Space Research Organisation (ISRO) has once again proved its mettle on the global stage. In a significant leap forward for India’s heavy-lift capabilities, the space agency has successfully demonstrated a unique "boot-strap" starting mode for its indigenous CE20 Cryogenic Engine. This development promises to revolutionize how future rockets carry weight into space.

Why is this test significant?

Currently, the CE20 engine serves as the powerhouse for the upper stage of the LVM3 rocket and is also qualified for the ambitious Gaganyaan missions. In standard operations, starting this engine requires a stored gas system to get the turbopumps spinning.

However, future space exploration requires rockets to perform multiple restarts while in flight to place satellites into different orbits. Under the old configuration, every restart would require carrying extra gas bottles and supporting hardware. This added weight eats into the vehicle's "payload capability," meaning the rocket can carry fewer satellites or scientific instruments.

The "Boot-Strap" Solution

To solve this weight problem, ISRO engineers worked on a boot-strap mode. This allows the engine to roar to life and reach a steady speed without needing any external start-up gas assistance.

The crucial test took place on November 7, 2025, at the ISRO Propulsion Complex (IPRC) in Mahendragiri. Conducted under vacuum conditions at the High-Altitude Test (HAT) facility, the CE20 Cryogenic Engine was fired for a duration of 10 seconds.

How they achieved it

The engineers employed a specialized multi-element igniter placed in both the thrust chamber and the gas generator. The sequence was precise:

• First, the thrust chamber was ignited.
• Next, the gas generator was lit using internal tank head conditions.
• Finally, the turbopumps kicked into gear without any external support system.

The test was a resounding success, demonstrating that the engine could build up pressure and maintain steady-state operation autonomously.

A Potential World First

This achievement is not just a win for India; it is likely a global first. ISRO has demonstrated the boot-strap starting mode on a gas-generator cycle cryogenic engine without any auxiliary support. This breakthrough paves the way for highly flexible future LVM3 flights, allowing for heavier payloads and complex multi-orbit missions without the burden of carrying heavy start-up systems.

Image Source: ISRO