India tests new and better restart method for upper stage of its biggest rocket
India’s space agency ISRO has successfully tested new restart method for the engine it uses on the upper stage of its LVM rocket, its biggest rocket that it also intends to use for its manned and interplanetary missions.
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.
In other words, the engine now be restarted numerous times, giving any payload attached much greater flexibility in positioning and orbital maneuvers. For manned missions this means it can be used to reposition the modules for India’s planned space station, maneuver its manned capsule Gaganyaan, and send interplanetary missions to the Moon and beyond.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
India’s space agency ISRO has successfully tested new restart method for the engine it uses on the upper stage of its LVM rocket, its biggest rocket that it also intends to use for its manned and interplanetary missions.
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.
In other words, the engine now be restarted numerous times, giving any payload attached much greater flexibility in positioning and orbital maneuvers. For manned missions this means it can be used to reposition the modules for India’s planned space station, maneuver its manned capsule Gaganyaan, and send interplanetary missions to the Moon and beyond.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

