As an Indian rocket is getting ready to put five British satellites into orbit on July 10, officials at the Sriharikota space port are also working on an Indian satellite launch, an official said on Monday.
India will launch a communications satellite GSAT6 sometime after July 10.
“Work is progressing smoothly for the July 10 night rocket launch. The PSLV (polar satellite launch vehicle) rocket is ready. We are carrying out the launch rehearsal now. We will be rehearsing the activities that are to be done on the launch day,” a senior official of Indian Space Research Organisation (ISRO) said on Monday.
According to him, the four stage/engine PSLV rocket in XL variant is slated to blast off at 9.58 p.m. on July 10 and the 62.5-hour countdown is expected to start at 7.28 a.m. on July 8.
The official said the Launch Authorisation Board (LAB) is slated to meet on July 7 and take a decision on the PSLV rocket launch.
Of the five British satellites, together weighing around 1,440 kg, three are identical DMC3 optical earth observation satellites weighing 447 kg. These will be put into a 647-km sun-synchronous orbit.
Of the other two satellites, CBNT-1 weighs 91 kg and also is an optical earth observation technology demonstration microsatellite, while the De-OrbitSail weighs 7 kg. This is an experimental nano satellite for demonstration of large thin membrane sail and drag deorbiting.
The three DMC3 and the CBNT-1 satellites are built by Surrey Satellite Technology Ltd. The De-OrbitSail is built by Surrey Space Centre.
According to ISRO, accommodating the three DMC3 satellites each with a height of about three metres within the existing payload fairing or the heat shield of the PSLV was a challenge. Thus, a circular L-adaptor and a triangular Multiple Satellite Adapter-Version 2 (MSA-V2) were newly designed and realised by ISRO for this specific purpose.
France’s SPOT 7 satellite weighing 714 kg was the heaviest single foreign satellite carried by a PSLV rocket till now. It was launched on June 30, 2014.
Meanwhile, the GSAT6 communication satellite is expected to reach Sriharikota space port on July 6 after it was flagged off from Bengaluru, the official said on the condition of anonymity.
He said the GSAT6 communication satellite will be put into space aboard a\ heavier rocket called geosynchronous satellite launch vehicle (GSLV).
The GSLV rocket’s first stage/engine has been assembled and the activities relating to that rocket assembly are progressing smoothly.
Only after the GSLV rocket launch the testing of a small model of reusable launch vehicle shaped like an aeroplane would be done, the ISRO official said.
Earlier, it was said the test reusable launch vehicle would happen in July 2015.
ISRO officials said that the test model reusable launch vehicle would be mounted on a strap-on solid booster of PSLV rocket with 9-tonne fuel.
At an altitude of 70 km, the model would get separated and would glide back to earth. The descent speed would be around 2 km per second.
“The descent speed would be controlled through the fins on the machine. In order to protect the equipment from friction heat when it comes back, necessary protective tiles are fixed,” the ISRO official said.
The experimental vehicle would weigh around 1.5 tonne which is a far cry from the actual vehicle that is expected to carry a satellite.
In December 2014, ISRO sent up a 3.7 tonne giant cup-cake shaped module – called Crew Module Atmospheric Re-entry Experiment – to study its re-entry characteristics, aero-braking and validation of its end-to-end parachute system.
A 630-tonne rocket went up to 126 km when the crew capsule got detached and fell into the Bay of Bengal, 20 minutes after the blast off.
The descent speed of the crew module was controlled by three parachutes.
However, the aircraft shaped vehicle will not have any parachutes to control the descent speed but the fins and other parts would do so.