Arianespace launch thread

[PB666]

Here we go again, the little chimpmunks are once again running around in their treadmills.

[Ultimate Steve]

My goodness, what a coincidence!

I watched the stream and later read that it was a failure.

Then just now I was scrolling reddit and saw this:

 

The launcher’s liftoff took place on January 25, 2018 at 7:20 pm. A few seconds after ignition of the upper stage, the second tracking station located in Natal, Brazil, did not acquire the launcher telemetry. This lack of telemetry lasted throughout the rest of powered flight.

Subsequently, 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.

And then I read the comment below that:

 

I'm both dismayed at the failure and impressed that the 2nd stage continued on "alone".

 

(Emphasis mine)

 

And at that moment, the song "Alone" by Alan Walker which was playing in the background reached the vocal section where it said "I know I'm not alone" so yay!

[PB666]

47 minutes ago, Ultimate Steve said:

My goodness, what a coincidence!

I watched the stream and later read that it was a failure.

Then just now I was scrolling reddit and saw this:

 

The launcher’s liftoff took place on January 25, 2018 at 7:20 pm. A few seconds after ignition of the upper stage, the second tracking station located in Natal, Brazil, did not acquire the launcher telemetry. This lack of telemetry lasted throughout the rest of powered flight.

Subsequently, 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.

And then I read the comment below that:

 

I'm both dismayed at the failure and impressed that the 2nd stage continued on "alone".

 

(Emphasis mine)

 

And at that moment, the song "Alone" by Alan Walker which was playing in the background reached the vocal section where it said "I know I'm not alone" so yay!

A three vehicles were carried safely to orbit by the hype train.

[Streetwind]

On one hand, successfully completing the mission despite loss of communication speaks for the robustness of the launch system. On the other hand, this really should not have happened, and needs a proper investigation. Here's hoping they figure it out quickly and fix it; they have an interplanetary flight in October that absolutely cannot afford to miss its window.

[GoSlash27]

4 hours ago, Streetwind said:

On one hand, successfully completing the mission despite loss of communication speaks for the robustness of the launch system. On the other hand, this really should not have happened, and needs a proper investigation.

 Unfortunately, the lifter did not successfully complete the mission. It placed the sats in the wrong orbit and now they'll have to expend more DV to correct it, which will shorten their operational life.

 I hope they find the source of this problem and get it corrected quickly.

Best,
-Slashy

[Streetwind]

25 minutes ago, GoSlash27 said:

It placed the sats in the wrong orbit

Oh, there is new information on this now? When I made my post, Arianespace's newsfeed simply said "both satellites on orbit", with no mention of said orbit being wrong; and neither customer had made a statement beyond "we have contact with our spacecraft".

*checks*

...Ah, I see. SES has put out a press release in the meantime, talking about increased orbit raising times. I suppose that does indicate the wrong delivery orbit.  

 

Edited January 26, 2018 by Streetwind
Typos, typos everywhere!

[PB666]

One of the satellites is an ION drive it will not lose any hardly any of its dV as it will take months to get to its proper orbit. As for either of them being in the wrong orbit a source of that information (hype) was not posted.

 

Quote

From CBS NEWS

Arianespace CEO Stephane Israel: "Ladies and gentlemen, I come to give you some information because we have had an anomaly on this launch," he told flight controllers and onlookers at the control center. "Indeed, we lost contact with the launcher a few seconds after ignition of the upper stage.

"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."

 

From spaceflight.com

Quote

Sources [unnamed] familiar with the launch said the SES 14 and Al Yah 3 spacecraft may not have been delivered to the exact orbits targeted by the Ariane 5, but officials shared no specifics on the orbital parameters Thursday night. - https://spaceflightnow.com/2018/01/26/ariane-5-va241-status-1/

Quote

With the benefit of an electric thruster orbit-raising package, the SES 14 telecom satellite is expected to be able to reach its planned position in geostationary orbit without major impacts to its mission, a space industry official [unnamed] said. https://spaceflightnow.com/2018/01/26/ariane-5-va241-status-1/

Its important when making spurious claims to provide the source.

Edited January 26, 2018 by PB666

[magnemoe]

44 minutes ago, Streetwind said:

Oh, there is new information on this now? When I made my post, Arianespace's newsfeed simply said "both satellites on orbit", with no mention of said orbit being wrong; and neither customer had made a statement beyond "we have contact with our spacecraft".

*checks*

...Ah, I see. SES has put out a press release in the meantime, talking about increased orbit raising times. I suppose that does indicate the wrong delivery orbit.  

I assume that the upper stage continued on its own autopilot but using only inertia navigation, no course corrections during burn. 

[tater]

 

[sgt_flyer]

1 hour ago, tater said:

 

https://www.reddit.com/r/Arianespace/comments/7siadj/rarianespace_ariane_flight_va241_ses14_al_yah_3/

Mmh - seems they released some orbital parameters, seems like they are ~17° off of their intended orbit :

 

Target : i=3°, A×P=45000×250 km

Current detected orbits (both sats, upper stage and Sylda - not necessarily in that order )

43174 ( 18012A ) i=20.64°, A×P=43163.63×232.36 km

43175 ( 18012B ) i=20.64°, A×P=43198.26×231.64 km

43176 ( 18012C ) i=21.01°, A×P=42790.30×168.65 km

43177 ( 18012D ) i=20.64°, A×P=43152.68×234.75 km

 

With no feedback from telemetry, seems like the upper stage could not correct it's trajectory...

it's still going to cost the satellites quite some delta-v:

Edit : Mmh - just for the inclination change, seems it'll cost the satellites roughly 450 dv (though i might have inputted the wrong numbers in the calc) - numbers used :

r2 = 43174 

r4 = ((6371*2)+232+43174)/2

r6 = 17

https://instacalc.com/42882

 

that's still going to reduce quite a bit the satellites service life in the end.

still, the upperstage managed to take those satellites in orbit despite complete loss of telemetry and corrections - not a small feat either  

 

Edited January 26, 2018 by sgt_flyer
Added inclination change dv calculator

[GoSlash27]

18 minutes ago, sgt_flyer said:

 

that's still going to reduce quite a bit the satellites service life in the end.

 

Sgt Flyer,

I haven't run the numbers myself, but yeah. This is why I disagree with the tweet calling it a "full mission success".

They were fortunate to have this happen with payloads that have sufficient DV to correct it. 

 I imagine finding the cause will be a bear.

Best,

-Slashy

[Dilir]

Just as a reminder :

 

But yeah, the orbit is a bit off:

http://spacenews.com/satellites-placed-into-incorrect-orbits-by-ariane-5-can-be-recovered-owners-say/

SES-14 stated that it will indeed take 4 more week to get to operating location, but it should not impact it's intended lifespan :

https://www.ses.com/press-release/ses-14-good-health-and-track-despite-launch-anomaly

As for Al Yah 3, no estimate was released yet.

[Streetwind]

As much as it smarts me (as an European) to see Ariane 5's amazing streak ended, I have to agree... based on usual conventions, this launch must be declared a partial failure. Something clearly went wrong with the rocket on ascent, and customer operational timelines were affected, so this is clearly not a full success.

Such a bummer. Before this flight, the Ariane 5 ECA variant was three successful flights away from scoring "most reliable heavy-class lifter in the history of spaceflight, period". This setback means it would need another 26 consecutive successes from now on to reach that mark... and the rocket likely won't fly that often anymore before it gets retired in favor of Ariane 6.

[PB666]

26 minutes ago, Streetwind said:

As much as it smarts me (as an European) to see Ariane 5's amazing streak ended, I have to agree... based on usual conventions, this launch must be declared a partial failure. Something clearly went wrong with the rocket on ascent, and customer operational timelines were affected, so this is clearly not a full success.

Such a bummer. Before this flight, the Ariane 5 ECA variant was three successful flights away from scoring "most reliable heavy-class lifter in the history of spaceflight, period". This setback means it would need another 26 consecutive successes from now on to reach that mark... and the rocket likely won't fly that often anymore before it gets retired in favor of Ariane 6.

The launch center is at 5'14" north it need a 2' burn to get to 3'N which does not explain the 21' inclination difference, this could mean that it was off by 18 or 24 degrees. But anyway lets just look at the dV requirement of SES-14

If orbit is 235 x 43,150 km this means that its a = (235000 + 43150000)/2 + 6371000 = 28,063,000 km with that we can derive e = 0.764 we can deduce the v at apo as being SQRT(mu (2/r - 1/a)) =1378 m/s. If the planned inclination change is made at this point then it is 428 to 560 m/second, which is nothing for an ION driven space craft. Thus burns can be reduced by combining them with the circularization burns.

In anycase this is still  a successful launch.

I should also point out that for a highly eccentric orbit, you really don''t care where its pXY coordinates are since in the process of gaining orbit the earth is always turning under that orbit until geostationary status is reached, you adjust the timing of your burns to intercept the desired station.

 

Edited January 26, 2018 by PB666

[mikegarrison]

Quote

SES 14 and Al Yah 3 were designed for 15-year missions. In its statement, SES said its satellite will still be able to meet its design lifetime, despite its delivery to an off-target orbit. Yahsat did not explicitly address its lifetime expectations for Al Yah 3.

https://spaceflightnow.com/2018/01/26/probe-into-off-target-ariane-5-launch-begins-ses-and-yahsat-payloads-declared-healthy/

[GoSlash27]

4 hours ago, Streetwind said:

As much as it smarts me (as an European) to see Ariane 5's amazing streak ended...

Streetwind,
 As a worldwide community of space- geeks, I think it's safe to say that we don't get wrapped up in nationalism or regionalism. We wish everyone good fortune in the peaceful exploration of space.

Best,
-Slashy

[insert_name]

nasa is getting involved in the anomaly investigation, also rumors of a programming error

http://spacenews.com/nasa-to-be-part-of-ariane-5-anomaly-investigation/

 

[PB666]

4 minutes ago, insert_name said:

nasa is getting involved in the anomaly investigation, also rumors of a programming error

http://spacenews.com/nasa-to-be-part-of-ariane-5-anomaly-investigation/

 

lol, talk about over-reactions. My bets are on a fault gyroscope or one flight guidance missprogramming.

[Canopus]

I read that the wrong inclination corresponded with the rotation of another launchpad. So it must have been programmed for the wrong pad.

[PB666]

1 minute ago, Canopus said:

I read that the wrong inclination corresponded with the rotation of another launchpad. So it must have been programmed for the wrong pad.

Whoops. A simple GPS based If statement would have fixed that, lol.

[Green Baron]

35 minutes ago, Canopus said:

I read that the wrong inclination corresponded with the rotation of another launchpad. So it must have been programmed for the wrong pad.

What a silly mistake, if it is correct. Sounds like too much confidence and routine ...

[tater]

The plus is that the vehicle is fine, and it was human error. Most of the time the problem with mature technology is in fact the squishy bit controlling it.

[sh1pman]

1 hour ago, Canopus said:

I read that the wrong inclination corresponded with the rotation of another launchpad. So it must have been programmed for the wrong pad.

This again? Didn't that recent Soyuz-Meteor launch teach them anything?

[insert_name]

1 hour ago, Canopus said:

I read that the wrong inclination corresponded with the rotation of another launchpad. So it must have been programmed for the wrong pad.

But ariane 5 only has a single launch pad, how does that work?

[Canopus]

13 minutes ago, insert_name said:

But ariane 5 only has a single launch pad, how does that work?

I will look into it, but maybe shared software with another launcher?

Edit: http://spaceflight101.com/ariane-5-va241/ariane-5-va241-anomaly-analysis/ interesting read. Maybe not programmed for another pad but definitely wrong program.

Edited February 1, 2018 by Canopus