In another important milestone in the Gaganyaan project, Indian Space Research Organisation (ISRO) successfully carried out the test-firing of the Low Altitude Escape Motor (LEM) of Crew Escape System, from Sriharikota, Andhra Pradesh.
The LEM is a distinctive special purpose solid rocket motor with four reverse flow nozzles and generates a maximum sea level thrust of 842 kN (nominal) with a burn time of 5.98 seconds (nominal).
The nozzle end of LEM is mounted at the fore end of the launch vehicle unlike at the aft end in conventional rocket motors to avoid exhaust plume impingement on the crew module. This necessitates the use of a reverse flow multiple nozzle in this solid rocket motor. The reverse flow nozzle implies the reversal of the exhaust gas flow direction in the nozzle region.
The main objectives were which included evaluation of motor ballistic parameters, validation of motor subsystem performance and to confirm the design margins, evaluation the thermal performance of nozzle liners; especially to confirm the erosion / ablative characteristics.