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Arianespace launch thread

should general ESA stuff get a seperate thread or be on this thread?  

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  1. 1. should general ESA stuff get a seperate thread or be on this thread?

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4 hours ago, Canopus said:

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.

Some excellent information there: seems like the root cause was an azimuth error that started from T=0, though the cause of the azimuth error is unknown. I'm moderately surprised range safety didn't terminate the launch; while the azimuth just barely skirted outside Korou's safety zone, the boosters were dumped way off-target, far outside the declared zones in the notices to airmen and mariners. I suppose falling on somebody in the ocean is relatively unlikely, and Ariane 5s do not come cheap, but that was still a very significant deviation from the intended flight trajectory.

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Interesting detail. According to http://www.magnetic-declination.com/ magnetic declination at the launch site is -18° 14' which is very close but opposite to the error in launch azimuth.

6 hours ago, Starman4308 said:

Some excellent information there: seems like the root cause was an azimuth error that started from T=0, though the cause of the azimuth error is unknown. I'm moderately surprised range safety didn't terminate the launch; while the azimuth just barely skirted outside Korou's safety zone, the boosters were dumped way off-target, far outside the declared zones in the notices to airmen and mariners. I suppose falling on somebody in the ocean is relatively unlikely, and Ariane 5s do not come cheap, but that was still a very significant deviation from the intended flight trajectory.

I would hazard a guess that range safety might be wary of blowing up an otherwise nominally functioning rocket so close to but still inside the edge of the permitted zone. There would be a definite risk of possibly toxic debris falling into the safe zone. The boosters and core splash zones were way outside the indicated areas though. It cannot be an easy job being a range safety officer.

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"elimination of double checking the flight program to reduce cost"

That could turn into an expensive cost reduction.

I doubt they do compass navigation as the sole means, variations change rapidly while flying around the earth and local variations exist as well and change over time. Marine charts have the the local deviation printed in them, as well as the rate of change.

 

Edited by Green Baron
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I doubt they do magnetic navigation at all. Inertial or INS+GPS most likely. I just thought someone may have made a declination correction where unwarranted, and that could be how wrong numbers got into the computers. Pure unadulterated speculation so far of course, there will be an investigation and a report in due time.

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27 minutes ago, tater said:

 

About time!

Next step would be realizing that big and heavily structured organizations are slow to adapt to changing conditions...

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Their job is to provide guaranteed access to space for European countries and have a domestic space industry, not competing with some hype-clowns. Looks like they do their job well...

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As an European, my opinion is that they could do way more for the space industry.

Close to where I live there are Thales-Alenia and Avio, but they are using only a minimal portion of the engineering, scientific and manufacturing resources available in the area.

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ESA has a similar problem to NASA: they need to keep money rolling into each member state, which is the main reason that Ariane 6 is an assembly of parts from dozens of subcontractors, and is why it still uses SRBs for example.

Ariane 6 will be much cheaper than Ariane 5, but will still not be competitive. It's too late to cancel the project, but they need to direct R&D funding into Prometheus and ArianeNext. Hopefully, they can keep costs low by reusing some of the infrastructure from Ariane 5 and 6, but it will have to be a whole new launcher.

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A very quick investigation, because the cause was very simple and obvious.

On one hand, a good thing, because it means Arianespace can proceed with future launches without a stand-down.
On the other hand, that doesn't make it any less embarrassing that the problem happened at all...

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Next flight is March 21. Ariane 5 • Superbird 8/DSN 1 & Hylas 4.

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Arianespace, but a Soyuz... which thread to post in, lol.

Regardless we have 2 launches within 12 hours if SpaceX stays on schedule. ~30 min after midnight in FL, then 11 hours later in Guiana.

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Hoping that this is indeed the resumption of Soyuz flights from the C.S.G. It must be almost a year since the good old Semiorka has not departed from Kourou, and the last time I looked at the schedule Arianespace was hoping to launch six flights in 2018.

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Under 2 hours til launch. Weather looks nice.

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Live launch coverage placeholder shows an Ariane 5, rather than a Soyuz, which threw me for a loop.

I already flew this mission once, but I'm tempted to delete the constellation I already have up, fix the core design (It doesn't taper properly) and the cantilever arms (they are separatron-actuated rather than proper counterweight-cantilever), and fly it again.

From an article earlier this week:

Quote

Each spacecraft weighs around 1,543 pounds (700 kilograms), and the Soyuz rocket’s Fregat upper stage will fire its main engine three times before deploying the first two O3b satellites into orbit 4,865 miles (7,830 kilometers) over the equator around two hours after liftoff.

A brief fourth firing of the Fregat engine will set up for separation of the other two O3b satellites in a similar orbit.

The orbit is five times faster than GEO, which I matched in my first run by placing the O3b sats in a 746.081-km equatorial circular orbit. But does anyone know why the Fregat will fire four times? I'm guessing the first is orbital insertion/circularization, the second raises the apogee to the target orbit, and the third circularizes...but what direction would it fire the fourth time before the second pair deployment?

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19 minutes ago, sevenperforce said:

Live launch coverage placeholder shows an Ariane 5, rather than a Soyuz, which threw me for a loop.

I already flew this mission once, but I'm tempted to delete the constellation I already have up, fix the core design (It doesn't taper properly) and the cantilever arms (they are separatron-actuated rather than proper counterweight-cantilever), and fly it again.

From an article earlier this week:

The orbit is five times faster than GEO, which I matched in my first run by placing the O3b sats in a 746.081-km equatorial circular orbit. But does anyone know why the Fregat will fire four times? I'm guessing the first is orbital insertion/circularization, the second raises the apogee to the target orbit, and the third circularizes...but what direction would it fire the fourth time before the second pair deployment?

There's a good chance one or two of them is a perigee kick. The Fregat stage has a burn time of 22.5 minutes, long enough for serious Oberth losses if trying to go straight from LEO to GTO.

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3 minutes ago, Starman4308 said:

There's a good chance one or two of them is a perigee kick. The Fregat stage has a burn time of 22.5 minutes, long enough for serious Oberth losses if trying to go straight from LEO to GTO.

So you're thinking the first burn for orbital insertion, the second and third burns to raise apogee, and the fourth burn to change the argument of periapsis for the second pair of sats?

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Weather is in fact not good. I was basing it on the still image (which I failed to notice was the wrong LV).

Stream live

 

Back to green, though.

 

Red.

New launch time in 30 minutes.

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Launch time is 10 after now. Assuming winds lessen at altitude.

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