Second mission of Soyuz-2.1B in 2016 from Guiana Space Center was scheduled for 08:48 GMT; it seems that nothing (of course apart from the weather – heavy rain is predicted for tomorrow in Kourou) will interrupt lifting two satellites under program of Galileo navigation system: Galileo Full Operational Capability FM10 and FM11.
Two satellites designed and manufactured by OHB System/SSTL will be launched two improve constellation of Galileo navigation system developed by ESA. Arianespace, launch service provider, decided about utilizing Soyuz-2.1b rocket with Fregat upper stage. Mission covers delivering two satellites to MEO orbit for designated orbit of altitude of 23522 km and inclination at 57.394°. Payload which was covered with ST fairing (4.1 m x 11.4 m) on 18 May 2016 weights 1429,6 kg. Both satellites have identical parameters: they weight 714 kg with following dimensions 2.7 m x 1.2 m x 1.1 m. After reaching orbital position, satellites will deploy solar arrays with span of 14.67 m which will provide 1900 W of power. During at least 12 years of operational service satellites will provide navigational signal on E5, E6 and E1 bands; they will also support with their additional payload COSPAT SARSAT maritime emergency system.
Soyuz-2.1b was developed in the early 2000s as improved version of Soyuz-2.1a for lifting large payload covered with ST fairing. In 276th mission, Arianespace will utilize Soyuz-2.1b equipped in Fregat upper stage and four strap-on boosters. Each booster is powered with single RD-107A with thrust at 838.5 kN, which burns 44413 kg of propellant (RG1/LOX). First core stage is powered by one RD-108A with thrust at 792.5 kN and fueled with 90100 kg of propellant (RG1/LOX). Third stage (boosters are considered as first stage in spite of fact that they start in this same moment as core stage) is equipped in one RD-0124 providing thrust at 297.9 kN with fuel reserve of 25400 kg of RG1/LOX. Fregat upper stage weighs 902 kg and takes 6638 kg of NTO/UDMH propellant. Its propulsion is single S5.92 engine which provides 19.85 kN of thrust. It is able to perform up to 20 burns and is equipped with independent guidance, navigation, attitude control, tracking and telemetry systems.
Flight plan of VS15 flight:
- T-0'16" - Ignition of core and four boosters
- T-0'14" - Engines will reach preliminary thrust
- T-0'01" - Engines will work with full thrust
- T+1'58" - All four boosters will be released
- T+3'39" - Fairing will be jettisoned
- T+4'48" - Core of the rocket will separate from third stage
- T+9'24" - Third stage will separate from Fregat upper stage
- T+10'24" - After one minute of ballistic flight Fregat will burn its engine for the first time
- T+23'32" - Fregat will stop its engine
- T+03h38'35" - Second burn of the Fregat
- T+03h42'57" - End of the second burn
- T+03h47'57" - Fregat will separate from both satellites
Good luck Arianespace !