Breaking: Ariane 5 loses contact with ground control after upper stage ignitionThe conditions of two satellites launched Thursday evening on an Ariane 5 were unknown after Arianespace lost contact with the rocket after ignition of the upper stage.
SpaceNews.com
Updated at 8:49 p.m. Eastern.
WASHINGTON — Two satellites launched Thursday evening on an Ariane 5 are in orbit following a harrowing lapse of communication between ground teams and the launcher within 10 minutes of liftoff.
The Ariane 5 lifted off at 5:20 p.m. EST from the Guiana Space Center in French Guiana carrying the SES-14 and Al Yah 3 communications satellites. About 27 minutes after liftoff, Arianespace’s live webcast of the launch indicated separation of the first satellite, SES-14. The second satellite, Al Yah 3, riding in the rocket’s lower berth, was scheduled to deploy about eight minutes later, but after 10 minutes the Arianespace webcast cut away from the live launch animation to pre-taped footage.
About 20 minutes later, Arianespace CEO Stephane Israel appeared on camera announcing an anomaly.
“[W]e have had an anomaly on this launch. Indeed, we lost contact with the launcher a few seconds after ignition of the upper stage,” he said during the launch broadcast. “Up to now, our customers do not have contact with the satellite. We need now some time to know if they have been separated, and where they are exactly, to better analyze the consequences of this anomaly.”
An hour and a half after Israel’s announcement, Arianespace released a statement saying “both satellites were confirmed separated, acquired and they are on orbit. SES-14 and Al Yah 3 are communicating with their respective control centers. Both missions are continuing.”
A live animation from Arianespace’s webcast showing separation of SES-14.
Arianespace did not immediately respond to a SpaceNews inquiry about if the satellites are in their intended orbits. SES-14 is an all-electric satellite that will require months to reach its geostationary slot — a timeline heavily influenced by launcher accuracy. SES said prior to launch that the satellite was expected to enter service in July.
Yahsat’s Al Yah 3 uses chemical propulsion and was designated for a super-synchronous orbit with an apogee of roughly 45,000 kilometers. Onboard propulsion has the job of circularizing the orbit to the geostationary arc at 36,000 kilometers over the course of five burns.
Ariane 5 lacked telemetry “throughout the rest of powered flight,” according to the company statement, with the lapse starting a few seconds after ignition of the upper stage when “the second tracking station located in Natal, Brazil, did not acquire the launcher telemetry.”
Israel, in his speech, apologized for the anomaly. “We know that there is no launch with no risk. We know that launch is always difficult, and tonight Ariane 5 has had an anomaly, so let’s take time now to better understand the situation of the satellites.”
Ariane 5 has completed 82 successful missions since a December 2002 failure that destroyed two satellites — Eutelsat’s Hot Bird 7 and France’s experimental Stentor communications satellite. Those 15 years of smooth sailing have allowed Arianespace to market the rocket as the champion of reliability.
It is unclear what impact tonight’s anomaly will have on Arianespace’s target of completing 14 launches this year — a goal announced just two weeks ago. The SES and Yahsat mission, designated VA241, is the first of those 14.
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Breaking: Ariane 5 loses contact with ground control after upper stage ignition