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Ariane rocket suffers rare launch anomaly Ariane rocket suffers rare launch anomaly
(about 4 hours later)
Europe's normally highly dependable rocket, the Ariane 5, experienced an anomaly during its latest launch.Europe's normally highly dependable rocket, the Ariane 5, experienced an anomaly during its latest launch.
Telemetry from the vehicle was lost about nine minutes into its flight from French Guiana, shortly after its upper-stage began the final push for orbit.Telemetry from the vehicle was lost about nine minutes into its flight from French Guiana, shortly after its upper-stage began the final push for orbit.
Uncertainty then followed as controllers tried to determine the status of Ariane and the satellites it was carrying.Uncertainty then followed as controllers tried to determine the status of Ariane and the satellites it was carrying.
Eventually, though, radio signals from the spacecraft were picked up.Eventually, though, radio signals from the spacecraft were picked up.
It seems the rocket did do its job - but beyond the sight of controllers on the ground.It seems the rocket did do its job - but beyond the sight of controllers on the ground.
However, it is also clear the Ariane 5 left the satellites in a less than perfect orbit.However, it is also clear the Ariane 5 left the satellites in a less than perfect orbit.
'Good health''Good health'
Arianespace, the company that operates the rocket from the Kourou spaceport in French Guiana, issued a statement explaining that a tracking station located in Natal, Brazil, failed to acquire data from the launcher as expected just after second-stage ignition.Arianespace, the company that operates the rocket from the Kourou spaceport in French Guiana, issued a statement explaining that a tracking station located in Natal, Brazil, failed to acquire data from the launcher as expected just after second-stage ignition.
"This lack of telemetry lasted throughout the rest of powered flight," it added."This lack of telemetry lasted throughout the rest of powered flight," it added.
"Subsequently, both satellites were confirmed separated, acquired and they are on orbit."Subsequently, both satellites were confirmed separated, acquired and they are on orbit.
"[The two satellites] are communicating with their respective control centres. Both missions are continuing.""[The two satellites] are communicating with their respective control centres. Both missions are continuing."
One satellite is owned by Luxembourg-based operator SES; the other belongs to UAE, Abu Dhabi-based Yahsat. They are both telecommunications platforms.One satellite is owned by Luxembourg-based operator SES; the other belongs to UAE, Abu Dhabi-based Yahsat. They are both telecommunications platforms.
The SES satellite, called SES-14, was manufactured by Airbus in the UK, at its Portsmouth and Stevenage plants, and at its Toulouse facility in France.The SES satellite, called SES-14, was manufactured by Airbus in the UK, at its Portsmouth and Stevenage plants, and at its Toulouse facility in France.
SES later confirmed the platform was in good health but its statement confirmed that the satellite did not separate from Ariane in the right place.SES later confirmed the platform was in good health but its statement confirmed that the satellite did not separate from Ariane in the right place.
Spacecraft are normally dropped off into a large ellipse around the planet which they must then first circularise and raise slightly before starting service. The platform uses its thrusters to do this.Spacecraft are normally dropped off into a large ellipse around the planet which they must then first circularise and raise slightly before starting service. The platform uses its thrusters to do this.
SES said that, as a consequence of Thursday's anomaly, its satellite would need an additional four weeks to reach the allocated orbital slot at 47.5 degrees West, 36,000km above the coast of northern South America.SES said that, as a consequence of Thursday's anomaly, its satellite would need an additional four weeks to reach the allocated orbital slot at 47.5 degrees West, 36,000km above the coast of northern South America.
SES-14 has an electric propulsion system that raises its orbit slowly but with great fuel efficiency. It was originally due to be on-station in July. The delay means August is now the expected arrival time.SES-14 has an electric propulsion system that raises its orbit slowly but with great fuel efficiency. It was originally due to be on-station in July. The delay means August is now the expected arrival time.
The operator said the 15-year lifetime of SES-14 had not been compromised.The operator said the 15-year lifetime of SES-14 had not been compromised.
Yahsat has yet to give further information about the status of its spacecraft, Al Yah-3, beyond Arianespace's statement. Likewise, Yahsat said its platform, Al Yah-3, had been "inserted into an orbit that differed from the flight plan".
Al Yah-3 would have been released after SES-14 because it was sitting in the lower position in the satellite stack on top of the Ariane 5. Al Yah-3, built by Orbital ATK in the US, carries a conventional chemical propulsion system. And although this does not have the fuel efficiency of electric thrusters, Yahsat seems confident the spacecraft will eventually reach the desired position in the sky.
The platform, built by Orbital ATK in the US, carries a chemical propulsion system. This raises the orbit quickly but does not have the same fuel efficiency, which could make it harder to reach the desired position in the sky if the separation was significantly off mark. "We are pleased to know that the satellite is healthy, and that the necessary steps are being taken to ensure the original mission is fulfilled," Masood M Sharif Mahmood, CEO at Yahsat, said in a statement.
What happened during Thursday's flight was a highly unusual occurrence.What happened during Thursday's flight was a highly unusual occurrence.
Although, famously, the Ariane 5 failed on its very first outing in 1996, it has since set a benchmark for reliability in the launcher business.Although, famously, the Ariane 5 failed on its very first outing in 1996, it has since set a benchmark for reliability in the launcher business.
Before this flight it had gone to space 82 times on the trot without mishap.Before this flight it had gone to space 82 times on the trot without mishap.
An inquiry will try to determine what exactly went wrong and assess whether any changes are required to the vehicle's design to ensure there is no repeat telemetry loss in future.An inquiry will try to determine what exactly went wrong and assess whether any changes are required to the vehicle's design to ensure there is no repeat telemetry loss in future.
On the current calendar, the Ariane 5 is due to make up to six more launches this year.On the current calendar, the Ariane 5 is due to make up to six more launches this year.
Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmosJonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos