ISRO's big achievement : Re-ignition of Cryogenic Engine

The CE20 cryogenic engine, powering the LVM3 upper stage, is already qualified for operation at thrust levels ranging from 19 to 22 tonnes in flight with a single start. The engine has also been qualified for the Gaganyaan missions. During nominal operation, the engine ignition is initiated under tank head conditions, followed by the start of turbopumps using a stored gas start-up system. For future missions, multiple in-flight restarts of the CE20 engine will be required for mission flexibility towards multi-orbit missions. However, with the present configuration, each restart demands an additional start-up gas bottle and associated systems, leading to a reduction in vehicle payload capability. Hence, achieving boot-strap mode start - where the engine builds up to steady operation without external start-up assistance - is essential. In this regard, a boot-strap mode start test on the CE20 Cryogenic engine was successfully conducted under vacuum conditions in the High-Altitude Test (HAT) facility at ISRO Propulsion Complex, Mahendragiri on 7th November 2025, for a duration of 10 seconds. A multi-element igniter was employed in both the thrust chamber and gas generator to facilitate boot-strap starting. In this test, following the ignition of the thrust chamber, the gas generator was ignited under tank head conditions, and the turbopumps were started without the use of the start-up system. Subsequently, boot-strap mode build-up and steady-state operation of the engine were successfully demonstrated. With this achievement, ISRO has successfully demonstrated boot-strap mode starting of a gas-generator cycle cryogenic engine without any auxiliary start-up system, perhaps for the first time in the world - a significant milestone towards enhancing the restart capability and mission flexibility of future LVM3 flights. #isro #space #india #upsc #generalknowledge https://learn.nimbus-edu.in ----------------------------------------------------------------------------------------------------------------------- Join this channel to get access to perks:    / @nimbuseducation   --------------------------------------------------------------------------------------------------------------------- Download "NIMBUS EDUCATION " App Play STORE : https://nimbus.on-app.in/app/oc/36300... "Introduction to Quantum Computing: Certification Course" -------------------------------------------------------------------------------------------------------------------- X(Twitter) https://X.com/purohitmanish LinkedIN   / manish-purohit-318b4613   Instagram   / purohitishere     / educationnimbus   Telegram https://t.me/nimbuseducation Whatsapp Channel: https://whatsapp.com/channel/0029VaA4... ------------------------------------------------------------------------------------------------------------------ Other channels : NIMBUS JEE NEET Channel : @NimbusJEENEET Space Flight LIVE :    / @spaceflightlive   #nimbuseducation #iitjee #neet #space #universe #cosmos #isro #nasa #spacex #physics #quantumtheory