It was a perfect launch. At exactly 02.08 a.m. Indian time on Saturday, the 800-tonne Ariane 5 launcher carrying two communications satellites weighing over 9000 kilos in its nose fairing, blasted off into space. India’s GSAT-8, the largest and heaviest satellite built by ISRO and its partners, was one of the two "co-passengers" on the flight. The other, an even heavier satellite weighing 5 tonnes was from Singapore and Taiwan.
Although the launch window was 90 minutes long, the countdown began on the dot at 17.38 local time and on the word "top" from the Jupiter Control Room, the cryogenic main engine was ignited. Just 7.05 seconds later the booster rockets roared into life, each containing 250 tonnes of dry powder that gave a thrust of 13,000 tonnes. As the launcher rose vertically, emitting a deafening roar with a blinding orange-red tail flame, there was palpable tension in the control room. For a full six seconds Ariane 5 climbed vertically then turned East, its flame appearing smaller until it disappeared from view amid the thick cumulus clouds hanging low over the equator.
But all was not over for the team of Indian scientists led by ISRO Chairman Dr. K. Radhakrishnan and Dr. T.K. Alex, Director of the ISRO Satellite Centre in Bangalore. It was only 31 minutes and 17 minutes later when GSAT-8 successfully separated from the final stage at an altitude of 249 kilometres above the equator, that a round of applause broke out.
Minutes later Dr. Radhakrishnan announced that ISRO’s Master Control Facility at Hassan near Bangalore had confirmed the reception of signals from GSAT-8. "They have taken charge of the command and control of GSAT-8 immediately after its injection into the geo-stationary transfer orbit," he said.
"Not over yet"
Speaking to The Hindu later, Dr. Radhakrishnan said he felt "relief and happiness" but warned that "all is not over yet".
"It is not enough to give birth to a baby, you must also be able to hear its heart beat. The next few days will be crucial. We will be stabilising the satellite in a geostationary orbit and that requires extremely delicate handling,” he told The HIndu. "This is another great moment for us. We lost two satellites last year in two unsuccessful GSLV missions so this in a sense makes up for that loss. The GSAT-8 is the heaviest and most powerful satellite we have ever built and Indians will be looking forward to the applications the satellite can provide such as the GPS Navigational system."
Dr. T.K.Alex said: “Of course for us now [it is abou] monitoring the satellite, firing the required boosters so that it is properly positioned into place and making sure we guide it to the exact spot where it is to be permanently located. There is already another satellite in that position. For us, we cannot really see it from earth except as a dot. We have to configure it in a figure of eight so that it cohabits harmoniously with its neighbour. It will take several days before we open the solar panels. The story is not over yet. In fact the story never ends because you need constant monitoring until the very end of the satellite’s life."
On Friday 19th, the launch vehicle with the two "passangers" already securely lodged in its nose faring was "rolled out" from the BAF or final assembly building. Vertically positioned and held in place by its two booster rockets, the cryogenic arms of the "umbilical tower" — that keeps the satellites cool — fills the tanks with liquid oxygen and hydrogen which have to remain at a temperature of minus 250° celcius. The launch table or "palette", a gigantic reinforced steel structure mounted on 32 wheels resting on a rail track, was towed to the launch site 2.8 kilometres away. Travelling at a maximum speed of 5 kms per hour the rocket, stood out against the dense green surrounding equatorial jungle.
ISRO officials gave the cost of the entire operation — the manufacture of the satellite and the launch charges as 675 crore rupees. Asked about the breakdown of launch charges, insurance costs and the actual cost of the satellite, Dr. Alex said he did not have the exact figures at hand. "But we negotiate the price for each launch. We are an old customer — this is our 14th launch with Arianespace and we are able to get substantial reductions,” he told The Hindu.
"The Indians are ace negotiators. It takes long for a project to get off the ground — this contract dates back to 2007 — but it always works out in the end. Although I cannot give you exact figures, a ballpark figure would be about 70 million dollars. Certainly they are given a good price because we are keen for this association to continue. And then, because Ariane is considered the most reliable launcher in the world, insurance costs are lower. Normally, it is about 5.5 per cent of the cost of the satellite and the launch price, but you can add on several options to cover transponder failure or a failure to deploy solar panels etc. So the insurance costs can vary greatly," Sebastien Dumenil, the Sales Director of Arianespace told The Hindu.
The French are also aware that India is working on perfecting its GSLV rocket and that in a decade or so India might not be using Ariane launchers. "Who knows? We have factored in India’s indigenous capacity into our calculations. Since satellites are growing bigger and heavier, that might take some time. But in the future we could become partners rather than customer and client. The Indians have already worked with us on building and launching third country satellites on two occasions. So the cooperation will continue. It might just take another form," he said