On August 28, 2021, the Indian space research organization (ISRO) successfully organized the first hot test of the System Demonstration Model (SDM).
The test of SDM was conducted for the Gaganyaan Service Module Propulsion System for 450 seconds at the test facility ISRO Propulsion Complex (IPRC), Mahendragiri, Tamil Nadu.
In a statement, the Bengaluru-headquartered space agency said that the performance of the system met the test goals and objectives, and there was a very close match with the prior test predictions.
The Indian space research organization also added that a series of hot tests are planned to simulate various mission conditions and the off-nominal conditions in the following months.
Moreover, a new test facility is also being established at IPRC, Mahendragiri, for testing the SDM.
Gaganyaan propulsion system testing
The space agency also highlighted that the Service Module is part of the Gaganyaan Orbital module and is situated below the crew module and still remains connected to it until re-entry.
The Service Module (SM) Propulsion System comprises of a unified bipropellant system composed of 440 N thrust engines (5 Nos.) and 100 N Reaction Control system (RCS) thrusters (16 Nos.) with MON-3 and MMH as Oxidizer and Fuel respectively.
According to the system, “the System Demonstration Model (SDM), consisting of 5 nos. of 440 N engines and eight nos.
Of 100 N thrusters was realized to qualify the propulsion system performance in the ground. A new test facility is established at IPRC, Mahendragiri, for testing the SDM.”
Earlier in July, ISRO had conducted the third long-term hot test on the liquid propellant Vikas engine to initiate the Gaganyaan mission. The founder of aerospace manufacturing giant SpaceX, Elon Musk, also congratulated ISRO for successfully conducting the test.
According to a statement by ISRO, the test of the Vikas engine was done for the core L110 liquid stage of the human-rated GSLV MkIII vehicle, as part of the engine qualification requirements for the Gaganyaan program.
The sole purpose of the Gaganyaan mission is to illustrate ISRO’s potential to send humans to low-earth orbit in an Indian launch vehicle and successfully bring them back to Earth.
Prime Minister Narendra Modi has also made the formal announcement of the Gaganyaan program during his Independence Day address on August 15, 2018.
A senior associate, Ajay Lele, working on space security and strategic technologies at the Institute for Defence Studies and Analyses, said that, “ISRO is currently testing various modules of the mission. However, we need two clean tests of the complete system before we send astronauts to space. And, that is going to take probably another two years”.
