GSLV Mk III lofts GSAT-29 communications satellite

The GSLV Mk III-D2 mission lifts off from Satish Dhawan Space Centre in Sriharikota on Nov. 14, 2018. Photo Credit: ISRO
India successfully conducted the second orbital mission of its heavy-lift GSLV Mk III launch vehicle. The rocket took to the skies Nov. 14, 2018, to deliver the country’s GSAT-29 communications spacecraft into space.
Liftoff occurred at 5:08 p.m. local time (11:38 GMT / 6:38 a.m. EST) from Second Launch Pad of the Satish Dhawan Space Centre in Sriharikota, India. The mission, designated GSLV Mk III-D2 (2nd Development Flight), was originally scheduled for May 2018, however it slipped to July and was later postponed several times, mainly due to the failure of the GSAT-6A satellite, which was orbited on March 29, but communications with it was lost three days later.
The loss of this spacecraft forced the Indian Space Research Organisation (ISRO) to perform additional checks of other satellites in the series, namely GSAT-7A, GSAT-11 and GSAT-29, targeted for launch in 2018. The Nov. 14 launch date for GSAT-29 was finally announced by ISRO in late October.
At 2:50 p.m. local time (9:20 GMT / 4:20 a.m. EST) Nov. 13, the countdown campaign for the launch commenced. During the conclusive phase of pre-launch preparations, engineers conducted final avionics health checks of GSLV Mk III, completed fueling operations of the launch vehicle and powered on the GSAT-29 satellite.

GSAT-29 satellite. Photo Credit: ISRO
Igniting its two S200 solid strap-on boosters, GSLV Mk III rocketed skyward to perform a brief vertical ascent before turning East toward the Bay of Bengal. The rocket’s L110 liquid core stage was ignited 1 minute, 50 seconds into the flight, which was followed by jettisoning of the strap-on boosters 29 seconds later.
The launch vehicle flew powered by L110 alone for some three minutes until this stage was also separated 5 minutes, 18 seconds into the flight. During this phase of the ascent, the protective payload fairing was detached about 3 minutes, 50 seconds after liftoff.
The rocket’s C25 cryogenic upper stage was turned on some three seconds after the separation of the core stage. The stage took control over the mission for the next 11 minutes until its CE-20 engine shut off 16 minutes, 28 seconds into the flight. The GSAT-29 satellite was deployed into space 15 seconds later at an altitude of approximately 129 miles (207.5 kilometers).
“India has achieved significant milestone with our heaviest launcher lifting off the heaviest satellite from the Indian soil. The launch vehicle has precisely placed the satellite in its intended orbit. I congratulate entire ISRO team for this achievement,” said ISRO Chairman Kailasavadivoo Sivan.
In the coming days the satellite is expected to carry out three orbit-raising maneuvers in order to reach a geostationary orbit (GEO, altitude of approximately 22,370 miles, or 36,000 kilometers), at the 55 degrees east orbital slot. It is planned to reside there for 10 years.
At some 3.4 metric tons, GSAT-29 is a high-throughput communications satellite based on the I-3K (I-3000) bus. Fitted with solar arrays, the spacecraft carries Ka/Ku-band transponders intended to provide high-speed bandwidth to Village Resource Centers (VRC) in rural areas.
Besides its main task, GSAT-29 is planned also to test several new technologies such as Q/V-band payload, data transmission through optical communication link and high resolution imaging from GEO.
Geosynchronous Satellite Launch Vehicle Mark III (GSLV Mk III) is India’s most powerful rocket. The 143-foot (43-meter) tall booster is capable of lifting up to 4.0 metric tons into a geostationary transfer orbit (GTO) and about 8.0 metric tons to low-Earth orbit (LEO).
First orbital flight of GSLV Mk III took place on June 5, 2017, when it orbited the GSAT-19 communications satellite. The rocket’s maiden orbital mission was preceded by a suborbital test launch on Dec. 18, 2014, with ISRO’s Crew Module Atmospheric Re-entry Experiment (CARE).
Wednesday’s mission marked India’s fifth launch of 2018. The country’s next orbital flight is currently targeted for Nov. 26, when a PSLV rocket is slated to send ISRO’s HySIS Earth-observing satellite and numerous CubeSats into space.
Video courtesy of SciNews
Tomasz Nowakowski
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