On Monday, December 27, 2021, at 13:10:37 UTC a Soyuz-2.1b rocket with a Fregat upper stage and 36 OneWeb satellites launched from Launchpad 6 of the Baikonur Cosmodrome. This was the twelfth launch under the OneWeb joint program.

The consecutive separation of the nine spacecraft groups from the Russian upper stage went in accordance with the flight sequence. Eleven active sections of the mission included three booster firings (the last one to take the upper stage into transfer orbit) and eight activations of stabilization, orientation and launch support propulsion unit necessary for safe separation of the satellites.

The foreign customers of Glavkosmos (part of Roscosmos) confirmed that all the contractual obligations were fulfilled. All the spacecraft were accepted for communication by the customer. Upon completion of spacecraft separation and injection, the Fregat upper stage will be deorbited, and the unburnt elements will be sunk in the non-navigable part of the Pacific Ocean.

The launch was ordered by European launch services provider Arianespace (OneWeb spacecraft launch operator) and Starsem under contracts with Glavkosmos. It was carried out by a joint team of Roscosmos subsidiaries: the Progress Rocket and Space Center, NPO Lavochkin, the Center for the Operation of Ground-Based Space Infrastructure Facilities, Russian Space Systems, Glavkosmos, as well as foreign customers.

Roscosmos conducted eight launches under the OneWeb program from two Russian cosmodromes during 2021. Five launches (March 25, April 26, May 28, July 1 and October 14) were performed from the new Vostochny launch site in the Amur Region and three launches (August 22, September 14 and December 27) from Baikonur. A total of 284 OneWeb satellites were injected into Earth orbit this year by Russian launch vehicles.