Ariane 5 Suffers Anomaly, Chinese Launch 3 Satellites
UPDATE: Agence France Presse (AFP) is reporting the problem with Ariane 5 involved more than just a loss of telemetry:
But a source told AFP the satellites did not detach from the rocket in the correct place after the craft followed an “imperfect trajectory”.
Arianespace said they were currently “repositioning the satellites in the right place using their propulsion systems” adding that the current status was “reassuring after strong concerns”.
I don’t see any further updates on the mission on the websites of Arianespace, SES or Yahsat. This leads me to believe the AFP report is accurate. If it had been a simple telemetry loss, Arianespace would have said so, and there would be press releases and social media messages declaring the flight to be a complete success.
Yahsat does have a link to a page with an update about the mission. It’s in Arabic so I ran it through Google Translate. The update doesn’t appear to go beyond Arianespace’s original statement about the spacecraft separating from the second stage and being in contact with control centers.
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Controllers lost contact with the upper stage of an Ariane 5 booster carrying a pair of communications satellites on Thursday. The loss telemetry began a few seconds after ignition of the stage and continued through the rest of the powered flight, Arianespace said in a statement.
“Subsequently, both satellites were confirmed separated, acquired and they are on orbit,” the company said. “SES-14 and Al Yah 3 are communicating with their respective control centers. Both missions are continuing.”
The precise orbital parameters of the geosynchronous communications satellites are unknown. SES-14 will use electric propulsion to reach its intended orbit while the Al Yah 3 will use a liquid bi-propellant transfer system.
Earlier on Thursday, China launched the fourth group of three Yaogan Weixing-30 satellites. A Long March 2C booster flew from the Xichang Satellite Launch Center.
Officially, the Yaogan Weixing are remote sensing spacecraft. However, analysts believe they are military reconnaissance satellites.
The flight marked China’s fifth successful launch of 2018. The nation is aiming to achieve more than 40 orbital launches this year.
16 responses to “Ariane 5 Suffers Anomaly, Chinese Launch 3 Satellites”
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So, the rocket worked fine and delivered the payloads as intended, but there was [just] a telemetry loss on the way?
Or, we’ll need to wait to find out how close the satellites were delivered to their intended orbits?
Exactly.
Incorrect orbit
Peter B. de Selding @pbdes
SES-14 owner @SES_Satellites: Off-target dropoff from @ArianeGroup @Arianespace Ariane 5 means all-electric propulsion to take 4 weeks longer than planned to get to GEO. Sat in good health, no other issues. Still awaiting word from @OrbitalATK & @yahsat official on Al Yah 3.
This is a partial failure if it didn’t place the satellites in the correct orbit.
From a quick web search the propulsion on SES-14 is provided by a Safran/Snecma PPS-5000 plasma propulsion unit. In addition to electricity (provided by solar arrays), plasma propulsion requires the use of something like xenon gas to generate the plasma. I wouldn’t call it “all electric propulsion” because once the gas tank is empty, the plasma propulsion unit won’t work.
So, this means that SES-14 will almost certainly have a diminished predicted lifetime due to the need to use some of its propulsion gas to reach its intended orbit. It will be interesting to find out how much lifetime will need to be sacrificed in order for it to be placed in the proper orbit.
‘All electric’ just means it doesn’t have a hybrid system using electric and chemical thrusters.
Got it. But to the layman, that may not be terribly clear.
Don’t forget, this is planned launcher for JWST!!
At this level of failure even Atlas V has suffered a failure. Yes, there is non-zero risk going on an Ariane V, but the launch bill is being paid by the ESA. Taking a higher risk in exchange for a inexpensive launch is an argument that’s been going about the past few years. Myself being one of those voices. It was a good way to get a European ‘buy’ into the JWST project after most of the systems definition was already done.
Look how much JWST weighs and the orbital it is going to. This thing would ride D4H not Atlas V.
Sorry, I did not make my point well enough. What I was trying to say is, the Atlas V is supposed to have a 100% mission success rate. But from the POV of reaching intended orbit, even it misses the mark of risk free. I did not communicate that very well. If you restrict the avail field of boosters that can take JWST to it’s orbit, they’ve all suffered from failures to make the intended orbit, sometimes by wide margins (Delta IV).
Yeah almost all active boosters have failed to take payloads into intended orbit at some point, even Falcon 9 which is pretty robust in that respect, of course that was a secondary payload and the primary payload customer (NASA) said no, even though it probably could have done it (98% chance)
Technically Delta 4H had not failed since original test flight. Although very hard to compare since so few missions compared to Ariane 5.
“almost” and yeah D4H doesn’t fly often,
this would have doomed webb withno way to fix it
Well the folks from Hawthorne or maybe the folks from Centennial or someone else can move the misplaced JWST to it’s proper destination at some future date. Provide that the JWST stays up long enough for someone to mounted a rescue. There is a grappling fixture on the JWST AFAIK.
Grappling fixture on JWST should be in the dictionary under optimism.