Arianespace successfully launched its fourth Ariane 5 mission of the year with the deployment of two more telecommunication satellites from the European Spaceport in Kourou on Thursday. The launch of Intelsat 33e and Intelsat 36 marked the heaviest launch to date for the European workhorse, with liftoff in the middle of the launch window at 22:17 UTC.
Ariane 5 Launch:
The Ariane 5 ECA (Cryogenic Evolution type A) – the most powerful version in the Ariane 5 range of rockets – was employed once again for this flight, a vehicle that is an improved version of the generic Ariane 5 launcher.
Those improvements relate mainly to the structure of the Ariane 5, allowing for an increased thrust and ability to carry heavier payloads into orbit.
Designed to place payloads weighing up to 9.6 tonnes into GTO, this increased capacity allows the Ariane 5 ECA to handle dual launches of very large satellites.
Given Arianespace now enjoys a full family of launch vehicles.
With the introduction of Soyuz at the Spaceport in 2011, Arianespace’s family was joined by the lightweight Vega vehicle, following her successful debut in 2012.
Arianespace will also be at the center of a new launch vehicle, the Ariane 6, which has been approved by the ESA members.
This latest mission was designated Flight VA232 in Arianespace’s launcher family numbering system and was the 231st Ariane mission since this series of vehicles entered operation in 1979.
T-0 targetted the start of a 45-minute launch window at the Ariane Launch Complex No. 3 (ELA 3). However, a boat in the range delayed the T-0 to the middle of the window.
The Ariane 5 mission had a total payload lift performance of 10,735 kg – which is a new record upmass number for an Ariane 5 mission to Geostationary Transfer orbit – by 5 kg.
This total included the two Intelsat satellites, as well as the launcher’s SYLDA dual-payload deployment system and the protective payload fairing.
The launch profile for the Ariane 5 began with lift off around seven seconds after the ignition of the main stage cryogenic engine at T-0, with the two solid-propellant boosters ignited, enabling liftoff.
The launcher first climbed vertically for 6 seconds, then rotated towards the East. It maintained an attitude that ensured the axis of the launcher remained parallel to its velocity vector, in order to minimize aerodynamic loads throughout the entire atmospheric phase, until the solid boosters are jettisoned.
The fairing protecting the payload was jettisoned at T+200 seconds.
Once this first part of the flight was completed, the onboard computers optimized the trajectory in real time, minimizing propellant consumption to bring the launcher first to the intermediate orbit targeted at the end of the main stage propulsion phase, and then the final orbit at the end of the flight of the cryogenic upper stage.
The main stage splashed down off the coast of Africa in the Atlantic Ocean (in the Gulf of Guinea).
At orbital injection, the launcher will have attained a velocity of approximately 9,365 meters/second, and was at an altitude of 640 kilometers.
Riding as the upper passenger in Ariane 5’s payload arrangement was Intelsat 33e. It was released approximately 28 minutes into the mission.
The spacecraft was built by Boeing using a 702MP platform, and will operate from an orbital position of 60 deg. With an estimated liftoff mass of 6,600 kg, this bird was the 52nd satellite built by Boeing (or its predecessors) to be launched by Arianespace.
Intelsat 33e is the second satellite in Intelsat’s next-generation, high-throughput Intelsat EpicNG series, joining Intelsat 29e – which was successfully lofted on an Ariane 5 mission performed in January.
Once in orbit, Intelsat 33e will meet the broadband demand for carrier-grade telecom services, enterprise networks, aeronautical connectivity and media services.
Sporting 20 C-band and 249 Ku-band transponders (36 MHz equivalent) and a 450 MHz Ka-band, the satellite is expected to serve in orbit for 15 years.
The second passenger was also an Intelsat bird, marking what is now a 30-year association between Arianespace and the satellite company.
In total, Intelsat 33e and Intelsat 36 were the 57th and 58th Intelsat satellites to be lofted by Arianespace, continuing a relationship that started with Intelsat 507’s launch in October 1983.
Deployed from Ariane 5’s lower passenger position, Intelsat 36 was built by SSL (Space Systems/Loral) on a 1300 platform in Palo Alto, California.
It was the 56th satellite using an SSL platform (and 50th with the 1300 configuration) to be launched by Arianespace.
Set to serve for 15 years, the satellite includes 34 Ku-band transponders and 10 C-band transponders.
The Ku-band payload was built to support MultiChoice, the leading direct-to-home platform in South Africa.
The C-band payload spot beams cover high traffic telecom centers in Europe, Central Africa, the Middle East, Asia and Australia; and a C-band wide beam provides coverage over sub-Saharan Africa for data and media services.
With a liftoff mass of around 3,253 kg, Intelsat 36 has a role in enhancing Intelsat’s media neighborhoods serving the South African and Indian Ocean region when starting operations from its 68.5 deg. East orbital position – where the satellite will be co-located with Intelsat 20, which was launched by Arianespace in August 2012.
The satellite’s separation occurred approximately 41 minutes after liftoff – completing the Ariane 5 mission.
“I would like to thank and congratulate the teams at Intelsat, Arianespace, and SSL who contributed to the successful launch of Intelsat 36,” said John Celli, president of SSL. “We are pleased to hear that the satellite, which is the second that we have delivered for Intelsat this year, is functioning according to plan.”
(Images via Arianespace and Intelsat).