Ariane 5 to Launch 4 Galileo Navigation Satellites

Image credit & copyright: ESA/Arianespace.

LAUNCH ALERT: Tuesday, December 12 2017 at 1836 UTC (13:36 EST) Arianespace will launch their massive heavy lift, Ariane 5 ECA rocket, designated VA240 carrying four Galileo navigation satellites (19, 20, 21 & 22) from Launch Site, Ensemble de Lancement Ariane-3 (ELA-3) at the Arianespace Spaceport in Kourou, French Guiana. This will be Arianespace’s 11 launch of 2017, the 96th launch of the Ariane 5 and its 5th launch in 2017.

Arianespace, Ariane 5 Rocket: is a 2-stage expendable launch vehicle that stands 54.8 m (179.9 ft.) tall and is 5.4 m (17.7 ft.) in diameter and is equipped with two solid rocket boosters. It comes in two variants (ECA & ES) and carries payloads weighing more than 10 metric tons to Geostationary Transfer Orbit (GTO) and over 20 metric tons into Low Earth Orbit (LEO). With only 2 failures to date and closing in on 100 launches, the Ariane 5 has earned it a place in history as an overall reliable heavy lift delivery system.

Ariane 5 ECA: is the Geostationary Transfer Orbit (GTO) workhorse and usually carries a payload of two satellites. The primary difference from the Ariane 5 ECA configuration is the use of a storable propellant upper stage, which can perform multiple burns to deploy payloads into the desired orbit.

Ariane 5 ES is tailored for low-Earth orbit missions with the Automated Transfer Vehicle (ATV), a resupply spacecraft for the International Space Station (ISS) that weighs more than 19,000 kg at liftoff. The ES Ariane 5 version also is capable of lofting satellites for Europe’s new Galileo space-based navigation system. The primary difference from the Ariane 5 ECA configuration is the use of a storable propellant upper stage, which can perform multiple burns to deploy payloads into the desired orbit.

Payload Fairing (PLF): The main payload fairing is a 2-shell fairing that’s 5.4 m. (17.7 ft.) in diameter and 20 m. (65.6 ft.) in length. Roughly 3 minutes and 100 km after liftoff the shells are pyrotechnically jettisoned. Inside the fairing of the ECA configuration is the structure that accommodates two satellites called “Systeme de Lancement Double Ariane 5” or SYLDA 5.

Etage Superieur Cryotechnique (ESC-A) Cryogenic Upper Stage (For the ECA configuration): Is 5.4m (17.7ft) in diameter by 4.7m (15.4ft) in length. It’s powered by a single HM-7B engine that burns liquid hydrogen and liquid oxygen (LOX/LH2) creating 14,000lb 6.5 t of thrust. Burn time for the second stage varies depending on the mission but can operate for around 945 seconds. The second stage also houses the Vehicle Equipment Bay (VEB-C) or “The Brain” which controls the entire vehicle autonomously and also transmits flight data back to the ground.

Etage Propergols Stockables (EPS) Second Stage (For the ES configuration): Is 3.9 m (12.8 ft.) in diameter by 3.35 m (11 ft.) in length. It differs from the ECA configuration because it is not cryogenic, meaning that it carries storable propellants. It’s powered by a single Aestus engine that burns monomethylhdrazine & nitrogen tetroxide creating 14,000lb 6.5 t of thrust. The second stage for this configuration can be reignited many times to suit the mission’s needs. The second stage also houses the Vehicle Equipment Bay (VEB-C) or “The Brain” which controls the entire vehicle autonomously and also transmits flight data back to the ground.

Etage dAcceleration a Poudre (EAP) Solid Rocket Boosters (SRB’s): 2 expendable SRB’s are attached to the Ariane 5 and they provide about 90% of the thrust at liftoff which equates to about 1200 t of thrust. They each stand 31.6m (103.7ft) tall and are 3m (10ft) in diameter. They are each powered by a single engine that burns solid fuel (Ammonium Perchlorate, Aluminum Powder and Polybutadiene); burn time is 135 seconds.

Etage Principal Cryotechnique (EPC) Core Cryogenic Stage (1st Stage): Stands 30 m. (98.4 ft.) high and has a diameter of 5.4m (17.7 ft.). It’s powered by a single Vulcan-2 engine which provides 136 t of thrust. It burns liquid hydrogen and liquid oxygen (LOX/LH2) and burns for 540 seconds.