Discussion Will the SpaceX push to reusability make ArianeSpace obsolete?

[MattBaker]

Maintenance wouldn't be cheap either.

I doubt it's into the billions. Besides I think at the point where we'd seriously think about building one we'd have materials that don't give a damn if they're hit by micrometeorites or pieces from chinese satellites.:shifty:

 

[Urwumpe]

I doubt it's into the billions. Besides I think at the point where we'd seriously think about building one we'd have materials that don't give a damn if they're hit by micrometeorites or pieces from chinese satellites.:shifty:

Enough drops of water erode the hardest stone.

 

[MattBaker]

I really hope that if you get the opportunity your space elevator isn't made of stone. At least not basalt.

 

[Pipcard]

Enough MMODs erode the hardest carbon nanotubes.

 

[N_Molson]

I guess that a space elevator would not use a "cable" in the sense we currently think it... Probably more a chain of atoms bound together by an insane amount of energy, driven in a sort of magnetic "channel" or something like that...

 

[Alexrey]

I don't know much about space elevators, but for them to be useful surely they would have to be built on the Earth's equator and extend to a height close to that of geostationary orbit? If they're built to a height of about 300km above Earth, we'll be in space, but we won't be going nearly fast enough to hop off the elevator and into orbit about Earth since the space elevator's rotational speed would only be around 1750km/h, and we need about 28000 km/h to get into LEO. I feel like I'm missing the point of these elevators though.

 

[Urwumpe]

I feel like I'm missing the point of these elevators though.

The point is, that, the closer you get to the altitude of the geostationary orbit, the higher your periapsis will get as well.

The problem is, aside of construction costs and robustness, that the elevator car will spent hours in the Van Allen belts - which does matter then for transporting humans.

I find launch loops more fascinating among the megaprojects, but I doubt we will ever put so much capital into one basket again.

 

[Alexrey]

So the point of a space elevator is to make gravity work with you instead of against you when getting spacecraft into orbit (i.e. you don't need to have the spacecraft's velocity vector perpendicular to the Earth's radial vector when "launching" from the top of the platform, but can instead point it somewhat towards Earth so gravity accelerates the ship)?

EDIT: Actually using gravity to help doesn't seem too plausible as it won't provide enough acceleration.

 

[Urwumpe]

So the point of a space elevator is to make gravity work with you instead of against you when getting spacecraft into orbit (i.e. you don't need to have the spacecraft's velocity vector perpendicular to the Earth's radial vector when "launching" from the top of the platform, but can instead point it somewhat towards Earth so gravity accelerates the ship)?

EDIT: Actually using gravity to help doesn't seem too plausible as it won't provide enough acceleration.

Again, remember that Earth rotates - you never start at zero velocity, but at increasing velocity. 6378 km above Earth, you already have 938 m/s. If you plug these numbers into the vis-viva integral, you can calculate the semimajor axis and this the periapsis altitude... and with some Excel later:

n | v (km/s) | r (km) | a (km) | rPe (km) | HPE (km)
1.00|0.469|6,378|3,194.6|11.2|-6,366.8
2.00|0.938|12,756|6,469.1|182.1|-6,195.9
3.00|1.407|19,134|10,044.2|954.5|-5,423.5
4.00|1.876|25,512|14,375.0|3,238.0|-3,140.0
5.00 | 2.345 | 31,890 | 20,441.6 | 8,993.3 | 2,615.3 6.00 | 2.814 | 38,268 | 30,867.1 | 23,466.1 | 17,088.1 6.57 | 3.083 | 41,930 | 41,931.3 | 41,932.6 | 35,554.6 7.00 | 3.283 | 44,646 | 56,315.8 | 67,985.5 | 61,607.5

Legend:

n|Distance from the center of Earth in multiples of the Earth radius
r|Distance from the center of Earth
v|Velocity of the elevator in that distance
a|Semimajor axis of the orbit, if you would be released in that distance
rPe| Periapsis radius of that orbit
HPe| Periapsis altitude

 

[Alexrey]

Sorry, but what are the units used in that table (I'm guessing n is not in seconds but some larger period of time)?

 

[Urwumpe]

Sorry, but what are the units used in that table (I'm guessing n is not in seconds but some larger period of time)?

I will correct that... sorry... was a quick and dirty Excel work.

 

[Alexrey]

Okay, so as I thought, a space elevator is only useful as a launch platform once its height approaches that of geostationary orbit.

 

[Urwumpe]

Okay, so as I thought, a space elevator is only useful as a launch platform once its height approaches that of geostationary orbit.

Yes, that is mandatory - below geostationary orbit, the centrifugal force would not produce enough tension to let the elevator counter its own gravitation. It would simply do the same like any other short rope - it would fall down.

And with geostationary orbit, you have to mean the centre of gravity of the elevator. That really means, without a counterweight, the elevator would need to extend about twice the distance to the geostationary orbit to not collapse. The heavier the counterweight, the less distance past geostationary orbit you need.

 

[Alexrey]

Wow, how one of these elevators will ever be built with such requirements is beyond me!

 

[Urwumpe]

Wow, how one of these elevators will ever be built with such requirements is beyond me!

Well, remember that we have also created much more expensive projects, than such a space elevator could ever get. The Eisenhower interstate highway system programme is one such example, it did cost $425 billion in 2006 dollars.

That would be approximately a cost of $10 million per kilometer space elevator.

But now the big difference: an interstate highway can be build in small controllable and managable steps. How could you do that with a space elevator? It is a all at once or nothing project for every tether.

It is doubtful that a space elevator could get such cheap, if you would have to expect a serious project overhead and serious waste of resources, because of the scale of the project steps.

 

[Cosmic Penguin]

Well the space elevator discussion is certainly stimulating, but since neither SpaceX and Arianespace are building one...

 

[RGClark]

A Hat Tip to SpaceX as Rebranded Airbus Defence and Space Takes Flight.
By Peter B. de Selding | Jan. 2, 2014

The hat tip to SpaceX, which on Dec. 4 successfully launched its first mission for a large commercial satellite fleet operator, SES of Luxembourg, was perhaps the most surprising of the comments.
“They have been able to work on industrialization of the Falcon rocket without being waylaid by development issues,” said one Airbus official, whose company is prime contractor for Europe’s Ariane 5 rocket.
“They needed nine times the power of their Merlin 1D engine for their intended markets. In Europe we would have attacked the issue with a beautiful [research and development] program, costing hundreds of millions, to develop an engine with nine times the power. What did SpaceX do? They put nine Merlin engines on the Falcon 9 first stage. The result: Problem solved.”
Http://www.spacenews.com/article/fi...branded-airbus-defence-and-space-takes-flight

This lesson learned could also be applied to Ariane 6 by using multiple Vulcain engines on the Ariane 5 core. Rather than spending billions on a new large liquid fuel engine, or on a new large solid booster under the current plan, use multiple copies of engines you already have on a stage you already have.

Bob Clark

 

[Urwumpe]

This lesson learned could also be applied to Ariane 6 by using multiple Vulcain engines on the Ariane 5 core. Rather than spending billions on a new large liquid fuel engine, or on a new large solid booster under the current plan, use multiple copies of engines you already have on a stage you already have.

[ame="http://en.wikipedia.org/wiki/Weasel_word"]Weasel word[/ame] alert again. "One Airbus Official" means: Somebody is saying something, is labelled as Airbus official and has a DAMN good reason to stay anonymous. For example the ridicule of the whole engineering department.

And there is just one tiny tiny problem with the perception of the people, involved in the creation of your post - ever dared to compare Falcon 9 to Falcon 1? :lol: Looks like just sticking 9 engines to the same core was not the solution - and was not fast: In 2006, SpaceX already described the Falcon 5 as a Falcon 9 missing 4 engines - the Falcon 9 development did thus at least take 4 years (more likely 8 years, but thats something only SpaceX knows). And would have been impossible without a huge bag of NASA money. Is it too much to ask, that the SpaceX fanboys on this far too small planet know their favorite companies history?

Looks more like the Falcon 1 was rather a Falcon 9 with just one engine.

 

[RGClark]

Just saw this article in French translated on another forum:

Réinventons le programme Ariane pour rivaliser avec les Américains.
LE MONDE | 08.01.2014 à 18h42 • Mis à jour le 09.01.2014 à 14h07 | Jean-Yves Le Gall (Président du Centre national d'études spatiales (CNES) )
http://www.lemonde.fr/idees/article...valiser-avec-les-americains_4344804_3232.html

Translation:

LET'S REINVENT THE ARIANE PROGRAM TO COMPETE WITH THE AMERICANS.
by: Jean-Yves Le Gall (Président du Centre national d'études spatiales (CNES) (President of the National Centre for Space Studies) [President of Arianespace 2007 to April 2013]
The three perfectly successful launches of the new American launcher Falcon 9, developed and operated by SpaceX, founded in 2002 in a Californian garage, bring many questions.
Indeed, it is the first time in history that a private corporation has managed to successfully fly and on the first try, too - a space launcher conceived with an antipodal/totally different approach to what has been done before.
These successes call out to us especially since SpaceX has announced their intent to dominate this industry, at a time where Europe has begun, at the initiative of France, the development of future launcher Ariane 6, which aims to enter service early next decade, and so will have SpaceX launchers as competitors.
VERY ATTRACTIVE PRICING
In coming months, Europe will have to decide on the final commitment to Ariane 6, as SpaceX has demonstrated that is can occupy the land (serve the market) with commercial launches at very attractive prices.
If we compare the SpaceX launcher to its competitors, it differs in three ways. First, it is perfectly adapted to government payloads: NASA and DoD satellites are an important part of its launch manifest, and an even greater one of its revenues, as the American government is willing to pay more for its own launches than is billed to commercial clients.
Second, its reduced size and ease of implementation lead to especially low operations costs that make it formidably competitive for commercial satellite launches: the last two Falcon 9 launches have brought the USA back to this market, from which they had been absent for many years, due to the lack of competitiveness and availability of their classic launchers.
Finally, its technical definition and industrial organization has, since the beginning, been designed with the goal of minimizing development and operations costs: instead of being a cutting edge technology launcher, the Falcon 9 uses proven technology engines that were easy to develop and inexpensive to industrialize/mass produce, and there are very few sub-contractors involved in launcher construction, which reduces production costs.
THE SPACE RACE
To sum it up, where classical methods have failed in the past ten years, the USA has terminated development of many classic launchers, after wasting many billions of dollars on them - , the Falcon 9 may well bring the USA back as leaders of the Space Race, while today they share it with Russia and China for government launchers and Europe occupies it for commercial launches.
Not to mention that SpaceX has been working on evolved versions of its launchers that, as soon as this year, might fly in an even more powerful version that might eventually be reusable, bringing down launch prices even more something that the Space Shuttle was never able to do, even though it had been designed to do just that!
Such an evolution would mean heavy consequences for Europe with, on the one hand the loss of market share and on the other, the embrittlement of our autonomous access to space that depends on the commercial success of our launchers, given the relatively limited number of European government satellite launches.
These are the findings that lead to define for Ariane 6 specifications that are related to Falcon 9s: a perfect adaptation to the launch of European government satellites, eased launch of commercial satellites, simplified design and tightened industrial organization to significantly reduce launch costs.
WE MUST REACT
It is clear that today, the USA are challenging us to compete with them by showing us the way with a system that puts into practice all those recommendations. And while, for many years, we feared competition from emerging economies with their cheap labor, competition is instead coming from the USA and their ability to innovate and to challenge themselves.
This situation bring back memories of the world of IT/computers in the early 70s, shaken by the coming of new companies that had one thing in common they all came out of garages in California. 40 years later, the space launcher industry, today considered a sovereign (government/national) industry, may well know the same upheaval.
Europe's space launch supremacy was hard-won/very expensive. Ariane 5 is the best launcher in the world, due to its reliability, conquering launch after launch since 2003, and it will remain the best since Europe has decided to support its operation and its adaptations to the evolving market.
As such, we must react to SpaceXs challenge and move forth with the development of Ariane 6. The goal isnt to make yet another Ariane launcher, but rather to reinvent Ariane development by taking the same turn that IT did in the 70s and SpaceX is taking now. This is the lesson we learn from the Californian garages.

Also, the acquisition of the JCSAT-14 launch contract by SpaceX was apparently a "steal" from Arianespace as the satellite company switched from the Ariane 5 to the Falcon 9.

A problem now for Arianespace is the expectation that they will lose more of their business to SpaceX. The Ariane 6 is not expected to come into service until 2021. How many more of their contracts will Arianespace lose until that time?
Arianespace believes they can make 10 to 15 launches per year at a $95 million launch cost with the Ariane 6. This becomes dubious when SpaceX will be charging half that.

The cost of a launcher is depended on its development cost, multi-billions of dollars for the Ariane 6, since these costs have to be recouped in the launch charges. Those development costs could be reduced by not developing a new engine and not developing a new stage but using multiple copies of the Vulcain on the Ariane 5 core. The development cost might be reduced by as much as an order of magnitude in that case, thus reducing also the needed launch price. Moreover they could then also keep up with SpaceX if they succeed in cutting launch costs by reusability.

Bob Clark

 

[Zachstar]

SpaceX has a limit on how fast they can launch safely just like any other company. And with 4k Video on the horizon it means the need for newer birds will grow. There is going to be plenty of launch contracts for everyone in my opinion. Well except Proton.