Indian Space Research Organisation (ISRO) has begun the countdown for the PSLV-C28/DMC3 mission at 07:28 am on Wednesday for its launch on Friday, July 10, carrying the heaviest commercial payload consisting of 5 British satellites.
The countdown was preceded on Tuesday with authorization given by the ISRO’s Launch Authorisation Board (LAB) after the Mission Readiness Review (MRR) committee cleared it. The PSLV C28 will loft off five UK-based Surrey technologies (SSTL) satellites into a 647-km sun-synchronous orbit.
The three DMC3 and the CBNT-1 satellites are built by Surrey Satellite Technology Ltd., while the nano-satellite De-OrbitSail was built by Surrey Space Centre.
The 62-and-half hour countdown of PSLV-C28/DMC3 Mission began this morning at 07:28 hours and the final lift off is scheduled at 21:58 hours in the night on July 10 and it is the night launch which required special nod from the board.
After its successful Mangalyaan mission, ISRO is gearing up for heavy satellite launches and the PSLV C-28 will test is capability in terms of commercial applications. Last year, the heaviest Frech satellite SPOT 7 weighing 714 kg was carried by PSLV C-23 mission in June.
ISRO has built a circular Launcher adaptor (L-adaptor) and a triangular deck called Multiple Satellite Adapter-Version 2 (MSA-V2) exclusively for the purpose and the lift-off process has 20 stages in all with the First Stage Ignition followed by Strap-on Ignitions and the second stage will follow the separation of the payload.
The second and third stages follow within 4 minutes from launch and the the third stage separation will be at 8 minutes and the fourth stage will follow soon within seconds.
The DMC3-1 will separate from the launch vehicle 17 minutes 56.58 seconds, the DMC3-2 in less than 0.20 seconds thereafter and third one DMC3-3 will follow suit in another 0.22 second and of them separate at 653.09 km altitude with a velocity of 7532.16 metres per second.
The nano satellite De-Orbitsal will separate at 18 minutes 36.08 seconds after lift off and the fifth and last will the CNBT-1 separation at 19 minutes 16.08 seconds at an altitude of 654.75 km with a velocity of 7532.42 metres per second, said ISRO in its brochure.