Menu Sign In Contact FAQ
Banner
Welcome to our forums

Galileo satellite system (merged thread)

Not that long ago they were saying Galileo would be so much more accurate than the US system, especially with the higher power output.

I don’t think accuracy has much to do with output power (i.e. output power of GPS is not limiting for many applications, especially aircraft guidance with full hemispherical sky view). But the Galileo E1 OS (and GPS L1C) signal has a significantly higher bandwidth over the GPS C/A signal, which is going to improve accuracy. Also, for certain applications, GPS satellite onboard clock accuracy is a limiting factor. No idea though if the Galileo satellite design is going to help.

They were even going to charge for encryption keys

Right now it seems they will mostly market the PRS signal to “law enforcement”.

Are they actually going to use this thing?

I hope so! Why should they abandon a perfectly working satellite just because it didn’t end up exactly where they planned it to?

LSZK, Switzerland

Surely that is a joke which symbolises so much of EU politics.

If you mean spending billions for the latest technology satellites and then entrusting their launch to the cheapest supplier on the market I fully agree. Why did we fund the development of European launchers with our taxes when they don’t use them to launch European spacecraft?

EDDS - Stuttgart

FOC launch…. with an acronym like that it couldn’t have gone right :-)

If you mean spending billions for the latest technology satellites and then entrusting their launch to the cheapest supplier on the market I fully agree.

Huh? It doesn’t make sense to me to bring up the nationalist argument. And anyway, the satellites were launched from Kourou, that’s about the most “european” territory close to the equator. And you want to launch close to the equator as you will then need less fuel.

Furthermore, Ariane’s track record isn’t impeccable, and Soyuz has an industry leading success rate, but oviously not 100%, either. Space launch is a risky business. BTW, it’s launch number 1824 for the Soyuz booster and 47 for the Fregat upper stage.

Why did we fund the development of European launchers with our taxes when they don’t use them to launch European spacecraft?

Why should the EU waste tons of money by using a launcher much too big for the task? Arianespace uses their Vega rocket for small payloads, the Ariane for large payloads, and they fill the gap in between with a cooperation with Russia, a joint venture called Starsem.

They plan to use Ariane to launch 4 Galileo satellites (as opposed to two with the Soyuz/Fregat launcher) in the future. I guess it just wasn’t ready and there were pressing needs to launch satellites as soon as possible (likely the frequency band occupation).

LSZK, Switzerland

Insurance will cover the incorrect oribital insertion. Any reduced capability or reduction of the useful life of the satellite will be covered.

EGTK Oxford

bq.And you want to launch close to the equator as you will then need less fuel.

It depends on the orbit. Galileo will be a swarm of satellites so it doesn’t matter so much where you launch from… more the climb out direction is most important because there will be less correction once in orbit.

They will probably, after the insurance is sorted, try and sell the two into academia/research/other application and then just build another two, cheaply for the space industry, as Galileo is the closest thing to a production line that currently exists in the industry.

Insurance will cover the incorrect oribital insertion. Any reduced capability or reduction of the useful life of the satellite will be covered.

The satellites are not insured. Unfortunately.

It doesn’t make sense to me to bring up the nationalist argument.

I was not after any national stuff here. But Galileo, Ariane, ESA are basically multinatioanlly subsidised programs to create and support an independent European space industry. Which is a good thing. And if there is no launcher that fits the requirement of the Galileo spacecraft it would have been an opportunity to develop one in the process.

EDDS - Stuttgart

And if there is no launcher that fits the requirement of the Galileo spacecraft it would have been an opportunity to develop one in the process.

It still doesn’t make sense to me to develop another launcher. There seems to be no shortage in medium mass launchers (such as Atlas, Delta, Falcon) that I don’t see the need for another one. It makes sense to me for Ariane to specialize on their heavy launcher, and offer the medium launch capability via a JV.

They will probably, after the insurance is sorted, try and sell the two into academia/research/other application and then just build another two

I fail to see why these satellites cannot be used for navigation

LSZK, Switzerland

I fail to see why these satellites cannot be used for navigation

There probably is no technical reason why not. But to change the orbit the satellites will have to expend a lot of fuel. They will be fuelled to planned life plus whatever the disposal strategy is (graveyard orbit/slow up and burn on reentry etc)… The graveyard orbit requirments will be fixed and therefore it will have to come from the life budget. Depending on what the full spare strategy is, they will have to eventually be replaced to keep the system functional. Why not manufacture the spares now while the teams are assembled across the supply chain, the tools exist and the knowledge is fresh… it will be expensive to rebuild later when that has all disbanded.

I don’t see the need for another one. It makes sense to me for Ariane to specialize on their heavy launcher, and offer the medium launch capability via a JV.

They are. Ariane 5 Upgrade and Ariane 6 is in thr pipeline

Last Edited by italianjon at 24 Aug 14:43
Sign in to add your message

Back to Top