Chennai, Dec 23 (UNI) The 24 hour countdown for the launch of the heaviest US Satellite
BlueBird-6 on board India's heavy lift rocket LVM3M6 began at the spaceport of Sriharikota
on Tuesday morning at 0854 hrs.
The launch would take place from the Second Launch Pad at 0854 hours tomorrow in a
purely commercial mission.
In a post on X ISRO said "24 hours to go! #LVM3M6 is set to launch the BlueBird Block-2
spacecraft tomorrow from SDSC SHAR."
"Final countdown begins. Launch on 24 Dec 2025 at 08:54 IST", it said.
This would be the heaviest payload to be launched by India this far and the heaviest
one to be placed into a Low Earth Orbit (LEO).
In another post, the Space Agency said "BlueBird Block-2 communication satellite
of AST SpaceMobile, USA, is part of a global LEO constellation enabling direct-to-
mobile connectivity.
"In this mission, LVM3-M6 will place the BlueBird Block-2 satellite, into the Low Earth
Orbit and is the largest commercial communications satellite to be deployed in Low
Earth Orbit. It will also be the heaviest payload to be launched by LVM3 from Indian
soil", it said.
After the Launch Authorisation Board (LAB) and the Mission Readiness Review
Committee gave the clearance for the mission, the countdown commenced during
which propellant filling operations would be taken up in the three stage vehicle.
About 16 minutes after the lift off, the satellite would be injected into a 520 km
Circular Orbit with an inclination of about 53 degrees to the equator.
This mission marks the 6th operational flight of LVM3.
The Indian Space Agency said LVM3 is the operational heavy lift Launch Vehicle
of ISRO and has a spectacular pedigree of completing eight consecutive successful
missions.
"LVM3-M6 is the Sixth Operational Flight of LVM3 and third dedicated commercial
mission to launch the BlueBird Block-2 spacecraft, which is the heaviest payload
(6100 kgs.) into Low Earth Orbit (LEO) in the LVM3 launch history", it said.
This mission is being undertaken as part of the commercial agreement between
M/s. NSIL and M/s. AST and Science, LLC an US based company.
BlueBird block-2 mission is part of a global LEO constellation to provide direct-to-
mobile connectivity through satellite .
This constellation will enable 4G and 5G voice and video calls, texts, streaming,
and data for everyone, everywhere, at all times. It features a 223m² phased array,
making it the largest commercial communications satellite ever deployed into the
LEO.
This would be the second mission for ISRO involving a US satellite after the
successful launch of of NASA-ISRO Synthetic Aperture Radar (NISAR) satellite
onboard GSLV–F16 on July 30, which has entered the Science Phase after
the Commissioning Phase was completed.
LVM3, developed by ISRO, is a three-stage launch vehicle comprising two solid
strap-on motors (S200), a liquid core stage (L110), and a cryogenic upper stage
(C25).
It has a lift-off mass of 640 tonnes, a height of 43.5 m, and a payload capability
of 4,200 kg to Geosynchronous Transfer Orbit (GTO).
In its earlier missions, LVM3 successfully launched Chandrayaan-2, Chandrayaan-3,
and two OneWeb missions carrying 72 satellites.
The previous launch of LVM3 was the LVM3-M5/CMS-03 mission, that was
successfully accomplished on November 2, 2025.
The satellite is part of a next generation of BlueBird Block-2 communication
satellites, designed to provide space-based cellular broadband connectivity
directly to standard mobile smartphones.
AST MobileSpace said BlueBird 6 is the first of its next-generation satellites.
When launched, it will feature the largest commercial phased array in LEO
at nearly 2,400 square feet. This represents a 3.5 times increase in size
over BlueBirds 1-5 and supports 10 times the data capacity.
"Our next-generation satellites will soon enable ubiquitous cellular broadband
coverage direct to everyday smartphones from space," Abel Avellan, Founder,
Chairman and CEO of AST SpaceMobile said.
"As an American company, we are proud to demonstrate U.S. leadership in
space innovation while pioneering the next era of global connectivity", he said.
AST SpaceMobile is accelerating production with 40 satellites equivalent of
microns on track to be completed by early 2026.
The company expects five orbital launches by the end of Q1 2026, with
launches occurring every one to two months on average to reach 45–60
satellites launched by the end of 2026 and support continuous coverage
across the United States and select markets.
This ramp-up is supported by nearly 500,000 square feet of manufacturing
and operations facilities worldwide, including roughly 400,000 sqft in the
United States, and a global workforce of nearly 1,800 people, the
overwhelming majority of whom are based in the U.S.
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