Isro clears CE20 cryogenic engine for next LVM3 mission after hot test

The Indian Space Research Organisation (Isro) has carried out the flight acceptance hot test of its indigenous CE20 cryogenic engine, clearing it to power the upper stage of the next LVM3 launch, designated LVM3-M7, according to Isro. The agency has not yet committed to a launch date for the mission.

The test was conducted on 6 July at the Isro Propulsion Complex in Mahendragiri, and marked the first time the agency used a newly developed Nozzle Protection System (NPS) during a flight acceptance test. Isro said both the engine and the new system performed satisfactorily, clearing the way for the engine to be refurbished and integrated with the C32 cryogenic stage being prepared for the mission.

During the test, the engine ran at a thrust level of 19.5 tonnes for 45 seconds before being ramped up to its maximum rated thrust of 22 tonnes for another 25 seconds. The CE20 engine powers the cryogenic upper stage of the LVM3, India’s heaviest operational launch vehicle, and has flown on eight consecutive LVM3 missions, including Chandrayaan-2, Chandrayaan-3 and three commercial launches.

The engine has also completed the human-rating qualification required for use in the Gaganyaan programme, India’s first human spaceflight mission.

Isro said the new Nozzle Protection System allows testing of the CE20 engine’s full area-ratio 100 nozzle under sea-level conditions, a process that previously required complex high-altitude test facilities to simulate near-vacuum operating conditions, reducing the resources needed for engine testing and enabling longer-duration tests.