Why in  news ? ISRO successfully conducted the bootstrap mode start test on the CE20 cryogenic engine.

• Test held under vacuum conditions at the High-Altitude Test (HAT) facility, Mahendragiri, on November 7 for 10 seconds.
• This is a major step toward enhancing restart capability and mission flexibility for future LVM3 flights.

About the CE20 Engine:

• Powers the upper stage of the LVM3 rocket.
• Already qualified for thrust levels of 19–22 tonnes with a single start.
• Used in Gaganyaan missions.
• Normally ignites under tank head conditions, with turbo pumps started via a stored gas system.

Why Bootstrap Mode Matters:

• Future missions may require multiple in-flight restarts for multi-orbit operations.
• Current system: each restart needs additional start-up gas bottles and systems.
• Bootstrap mode: engine reaches steady operation without external start-up assistance, reducing weight and complexity.

Significance for India’s Space Program:

• Enhances mission flexibility for LVM3 rockets.
• Supports multi-orbit and complex mission profiles.
• Key technological step for advanced cryogenic engine operations.

About LVM3 ROCKET:

Overview:

• LVM3, also known as Launch Vehicle Mark-3 (GSLV Mk III), is India’s heavy-lift launch vehicle.
• Developed by ISRO to carry heavier payloads into geostationary and low Earth orbits.
• Designed to support satellite launches and human space missions (like Gaganyaan).

Structure:

• Two solid rocket boosters (S200) for initial thrust.
• Core liquid stage (L110) using UH25 + N2O4
• Cryogenic upper stage (C25) powered by the CE20 engine for final orbit insertion.

Capabilities:

• Can lift up to 4 tons to GTO (Geostationary Transfer Orbit).
• Can lift up to 8 tons to LEO (Low Earth Orbit).
• Supports multi-orbit missions with the CE20 engine’s restart capability.

Significance:

• Heaviest rocket developed by India, bridging the gap between small/medium rockets and heavy-lift requirements.
• Critical for India’s satellite programs, space exploration, and crewed missions.
• Increasingly used for advanced missions requiring precise orbital insertion.