ISRO achieves major milestone for Gaganyaan Program; test-fires astronaut safety system

ISRO, on August 10, achieved a major milestone in its preparations to launch the Gaganyaan Program which starts later this decade. The agency revealed that it successfully carried out a test fire of the Low Altitude Escape Motor (LEM) of the Crew Escape System (CES) at the Satish Dhawan Space Center in Sriharikota, Andhra Pradesh.

The LEM is the component that would allow the CES to break away from the crew module in case of a mishap where astronauts need to be rescued. "LEM is a distinctive special purpose solid rocket motor with four reverse flow nozzles and generates maximum sea level thrust of 842 kN (nominal) with a burn time of 5.98 s (nominal)," ISRO said in its official statement.

The agency explained that the LEM would be mounted at the fore end of the launch vehicle unlike at the rear end in conventional rocket motors to avoid the exhaust plume's effect on the crew module. In its statement, ISRO also listed the following objectives that it achieved during the static fire test. 

• Evaluation of motor ballistic parameters
• Validation of motor subsystem performance and confirmation of the design margins
• Evaluation of the thermal performance of nozzle liners; especially to confirm the erosion/ablative characteristics
• Validation of the integrity of all interfaces
• Evaluation of the HMSA-based ignition system performance
• Evaluation of side thrust due to misalignment and variation in flow and other functional parameters including flow reversal

When will the Gaganyaan Program begin?

The Gaganyaan Program will first begin with two uncrewed trial missions before sending Indian astronauts to the low-Earth orbit (LEO). According to Union Science and Technology Minister, Jitendra Singh, the preparations for the Gaganyaan program are in full swing and the first two trial missions are expected to be completed between 2022 and 2023. However, Somanath, in June, revealed that ISRO's first manned mission would be possible only after 2023 as the agency is doubling down on the safety systems of the crew capsule. 

"It is a very important mission. We have to be extremely careful when we send humans to space," Somanath said at a press conference as per PTI. "If we want to fly astronauts, we need to first prove the safety system and it has to go through many tests. We are trying to do that this year. I don’t want to end up doing the Gaganyaan program with a disaster," he further said. 

Image: ISRO