While the PSLV mission is scheduled to launch earth observation satellite-6 (EOS-6) or Oceansat-3 in the early part of April, important tests under the small satellite launch vehicle (SSLV) and reusable launch vehicle (RLV) programmes have been lined up in the weeks preceding and following that. A Chandrayaan-3 landing test too is scheduled in March.
With a quick formal review of the programme having been completed by Isro chairman S Somanath earlier this month, the project team is burning the midnight oil to make the launch possible this year.
“We are trying to launch it this year, but we will take a final call on the launch schedule later. A lot of tests that were pending are now being carried out. One major test would be using a hanging condition. For Chandrayaan-2 we had done this at Mahendragiri, where the landing experiment was simulated. For Chandrayaan-3 we will be doing the same at the Satish Dhawan Space Centre, Sriharikota (SDSC-SHAR),” Somanath told TOI.
For this test a unit almost similar to the lander — the propulsion system — will be used to study nominal and other performances. The hardware is already at the spaceport in Sriharikota and Isro is preparing for the test.
Multiple sources in Isro, while pointing to various ongoing activities, said that some crucial tests part of the RLV technology demonstrator (RLV-TD) programme have been happening at Challakere some 220km from Bengaluru.
Isro chairman S Somanath told TOI Isro has been carrying out a series of (captive) tests over the past few weeks at Challakere, all using an engineering model of the RLV-TD and that the one carried out on Saturday was the final helicopter run in that series.
“In yesterday’s (Saturday) test we used a flight model. Now, we have to go back and analyse data from the flight model test. We need to look at all information and analyse if it reached the correct location, instrumentation health and other parametres. Any corrections felt necessary in the software will be done and the hardware will go back to Trivandrum (Vikram Sarabhai Space Centre) where it will go through a full simulation test before coming back in April first week for the landing experiment (LEX),” Somanath said.
The RLV-LEX, which will be demonstrating one of the critical technologies — the approach and autonomous landing on a runway, as reported by TOI earlier, will push it closer to an orbital re-entry experiment (ORE).
In the LEX, the vehicle will be carried using a helicopter to an altitude of about 3km to 5 km and released at a distance of approximately 4km to 5km ahead of the runway with a horizontal velocity. After the release, the RLV glides, navigates towards the runway and carries out a conventional autonomous landing with a landing gear.
The space agency, which is hoping to carry out the first developmental flight of the SSLV — to put into orbit EOS-2 or Microsat and marking the beginning of a new class of launch vehicles in India — will conduct an important test in the next couple of days.
“…The static test of the first stage of SSLV will be done in the next couple of days,” Somanath confirmed, without elaborating on the first developmental flight.
Designed to meet launch demand requirements in a cost-effective manner, SSLV is a three-stage all-solid vehicle with a capability to launch up to 500kg satellite mass into Low Earth Orbit (LEO).
Earlier, Isro had completed the SSLV Payload Fairing (SPLF) functional qualification test successfully and other testing activities are in progress.