In collaboration with Starsem and Roscosmos, Arianespace launched 34 new internet communication satellites aboard a Soyuz 2.1b for the OneWeb 9 mission. The flight marks the 8th operational launch of OneWeb satellites and brings the total number in orbit to 288: 48% of the 600 satellites required for global coverage with an additional 48 on-orbit spares for a total phase one constellation size of up to 648 satellites.
The launch was scheduled for Thursday, August 19; however, a rare scrub was called seconds before liftoff. A second attempt was first scheduled for Friday. Liftoff occurred on Saturday, August 21 from Site 31/6 at the Baikonur Cosmodrome in Kazakhstan at 22:13:40 UTC (18:13:40 EDT).