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Airbus Unveils Its First Stage Reuseability Concept
schwit1 writes: The competition heats up: Airbus unveiled Friday its prototype design to recover and reuse the engines and avionics of its Ariane rockets. From the article: "The Airbus team concluded that SpaceX's design of returning the full stage to Earth could be simplified by separating the propulsion bay from the rest of the stage, protecting the motor on reentry and, using the winglets and turbofans, return horizontally to a conventional air strip. "We are using an aerodynamic shield so that the motor is not subjected to such high stress on reentry," [technical director Herve] Gilibert said. "We need very little fuel for the turbofans and the performance penalty we pay for the Ariane 6 launcher is far less than the 30 percent or more performance penalty that SpaceX pays for the reusable Falcon 9 first stage." Gee, for decades Arianespace and Boeing and Lockheed Martin and everyone else in the launch industry insisted it made no economic sense to try to recover and reuse the first stage of their rockets. Then SpaceX comes along and makes an effort to do so, without as yet even coming close, and suddenly everyone agrees it is economically essential to do it as well. Isn't competition wonderful?
Why reuse something when you can trick governments to pay for it again. That make perfect economic sense until someone reveals the fraud.
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If you just want to see how it works, scroll down to the video at the end. They don't really explain it very well in the text.
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The idea that SpaceX "did not even come close" is ridiculous. It was the FIRST to operate on the principle that it was practical, and has twice now come very close to getting it done. In only... what... 4 tries? On a target far smaller than the continents aimed at by Russia and EU?
I find this whole announcement to be saying: "Yeah, us too! Maybe a few years from now."
It's not as much of a race as you might think.
From TFA, Airbus is going to be spending the next five years finishing Ariane 6. Then, AFTER they're done with that, they'll start serious work on reusability.
On the other hand, SpaceX is already flying the reusability testbed(s), and running the tests required to refine the software to the point that it words as intended.
So it looks like a race that SpaceX is pretty much guaranteed to win, what with the ten year head start....
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So its basically the Vulcan concept, a detachable avionics/engine package at the back and an expendable everything else. I suppose its an improvement from what we currently have but not by much. The only real difference from Vulcan is that instead of being snagged out of the air by a helicopter it glides back to some location under some power. I suppose I can see why Airbus and ULA are going for such concepts, they should be pretty cheap to develop (though I am sure they'll try to squeeze every dollar they can out of their respective benefactors), are relatively low risk and will still let them justify big launch bills with tank/upper stage replacement. But if SpaceX can pull off a Falcon first stage recovery even a majority of the time they'll blow this and Vulcan out of the water. Fuel is cheap, replacing tanks and stages is expensive.
everyone else in the launch industry insisted it made no economic sense to try to recover and reuse the first stage of their rockets.
Yes, that was then - long ago. Things are different now. For instance, who in the 90s, knew you could get 8GB of computer storage at less than $15 those days? It's reality now.
They may win as soon as July 22nd, when the Falcon 9 is scheduled to land at Vandenburg AFB. It'll be really interesting to see how 'reusable' the first stage is after the engineers have a chance to inspect it thoroughly.
This has the look of a paper concept that nobody's put any engineering work into yet. Some possibly show-stopping engineering challenges:
1) The air-breathing engines are dead weight dragged most of the way to orbit. And turboprops and turbofans are pretty damned heavy compared to rocket engines: for many applications, the weight of fuel and tankage is so much greater than the engines that engine mass is irrelevant, but that's not the case here. SpaceX's design makes use of engines that need to go to space anyway.
2) Looking at the videos, the design relies on folding propellers that deploy in flight. This is ... not an easy thing to do. I'm not aware of any aircraft larger than a duck that uses this technique, even on carrier-based aircraft where space is at a premium.
3) While rocket engines are pretty lightweight compared to turbine engines, it's still a lot of weight to fly back home. The video shows a flyback aircraft with very short stubby wings. In addition, the wings can't be asymmetric lifting airfoils or they'd push the rocket sideways during lauch: the have to be flat boards. The return vehicle is likely to have a very high stall speed, making landing a challenge.
4) The video shows no details on how this propulsion module is attached to the fuel tank above it. This is difficult: enormous fuel and oxidizer pipes need to pass through the nose of the propulsion module, along with gigantic clamps attaching it to the fuel tank... but this surface is exposed to re-entry heating on the flight back. How do you route plumbing and avionics through your heat shield?
"The Airbus team concluded that SpaceX's design of returning the full stage to Earth could be simplified by separating the propulsion bay from the rest of the stage, protecting the motor on reentry and, using the winglets and turbofans, return horizontally to a conventional air strip."
Interesting definition of "simplified" they're using. They're not even recovering the entire first stage, and they're basically bolting a jet airplane onto it to achieve that much. Propellant is as cheap as dirt, they're avoiding paying tens of thousands of dollars in propellant by instead paying for jet aircraft maintenance and operations and an entirely new set of cryogenic tankage and a substantial amount of aerospace vehicle structure for each flight. SpaceX is just making the first stage a bit bigger (and looking at things like additional propellant chilling to increase density) so it has the extra capacity required.
"We are using an aerodynamic shield so that the motor is not subjected to such high stress on reentry"
Thus solving an issue that SpaceX has already shown isn't actually a major problem...they have been regularly bringing entire intact first stages through reentry and down to sea level for some time now.
As for SpaceX not "coming close"...their second attempt actually brought the vehicle to a halt on the landing pad, though with mangled landing gear, and the reasons for the control issues during the final burn are well understood. They are extremely close...odds are quite good that their third attempt (in a bit under 2 weeks) will be a success.
>if X launches from Texas, is there a nice place to land the first stage?
I'm not 100% certain, but my understanding is that the plan is to, depending on the amount of extra fuel allowed by unused payload capacity, either fly directly back to the launch pad, or land on the floating barge to refuel and *then* fly itself back to the launch pad. Though I remember some talk about SpaceX leasing one of the more remote and durable launch sites at Cape Canaveral, Florida, so I imagine they plan to eventually land there for refueling rather than on a barge in the open ocean, with the associated much greater weather sensitivity.
It may seem kind of wasteful in terms of both fuel use and engine wear and tear (though I believe only one of the nine engines is used on the return flight), but consider that the first stage is about 45m tall (around 15 storeys), with an empty mass of about 25,000kg (approximately the maximum mass of a loaded 20-ft shipping container). The size means it's pretty much impossible to transport over normal roads, and the mass means that only the largest military cargo helicopters could handle it. And I would assume it's not designed to survive significant lateral stresses (no point in normal usage = wasted mass on structural supports = reduced payload), so laying it on its side to transport it by ship or truck would probably be a major challenge. So either you build and maintain a specialized transportation vehicle, or you just let the thing do what it was designed for and fly itself.
>How far downrange was the barge, and what is that far from TX.
I've heard 400km, though I couldn't give you a reliable source. And obviously that's fairly trivial to extend considering the first stage is already hurtling downrange at high speed when the second stage separates. If it simply "glided" down to to cruising speed, just maintaining high altitude (low air resistance) instead of actively decelerating, it could extend that range considerably while likely consuming even less fuel (obviously the fuel required for the return trip would increase, but that has no effect on payload capacity).
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I think you're talking about the Jason-3 launch. That's actually a couple launches away, though it'll be their first landing attempt on the West Coast.
CRS-7 is launching June 26th (bumped back a bit, probably to let them reshuffle things to account for cargo that was supposed to be delivered on the last Progress) from Cape Canaveral. They are going to attempt a landing...maybe on land instead of the ASDS.
They've also got a geosynchronous sat launch in mid-July with the first "enhanced" F9 v1.1...that might have the capacity for a landing, which previous geosynchronous launches didn't have enough performance to attempt.
30% launch cost reduction is a huge deal. It is considered good ROI in many areas, so things which previously could only break even become financially viable, and in fact a risk worth taking.
Here's to hoping they keep true to the 30%!
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Is the airbus project worth anything? I have no idea. But the more money thrown at this issue the happier I am really.
We need to get into space and we've allowed our space programs to atrophy.
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So they bolt on a pair of wings, add some propellers that have to be deployed from a casing that protects them during launch, oh and another stage separation event, a mechanism for separating the fuel tank from the engine.
And that's supposed to be simpler than some hydraulic landing legs and grid fins?
And carrying all those additions to space doesn't cost them any extra fuel?
They're right that reusability doesn't make much economic sense at current flight rates. NASA and Boeing looked at recovering Saturn V stages in the 60s, and determined that they'd need about 60 launches for the development and operational cost of recovering and refurbishing the stages to become lower than just throwing them away. This would probably require less, as they wouldn't be dumping the stage into the sea and trying to clean it up, but it will still probably require quite a few years at current launch rates to pay for itself.
SpaceX seems to be trying to get around that by cutting costs so low that the market grows exponentially. But there's a big gap between rockets a government can afford to launch a satellite on and rockets Joe Sixpack can afford to fly on for a space vacation where there's no clear and proven market.
Large government contractors live or die suckling the tits of taxpayers... and their internal goal is NOT to solve the problems they're brought in to solve (the paperless initiative to reduce costs and ALSO as a side effect make all government records indexable and searchable for example) but to maximize billable hours.
It makes perfect sense to say it isn't economically feasible to make the first stage of spacecraft reusable; because for them it ISN'T an economically sound business model. It would reduce their total revenue for these projects. For new players, it absolutely makes perfect sense because it is a new market which established players will not touch with a ten foot/3m (notice the inaccurate conversion of english to metric, quite appropriate for aerospace contractors ;) ) but new players who want to break into the market are seizing as an opportunity to get established in the industry.... so of course now that practical designs, even if flawed, are proving to be achievable they are absolutely terrified of being forced to unlatched from the teat. That has them scared so they will of course now begin in earnest to develop more reusable spacecraft because they work on such a large scale that losing just a couple of contracts where they have designed their business model to be as inefficient as possible in order to maximize net profits could bankrupt them very quickly.
This business model will also make affordable space tourism and arriving at next generation, more efficient spacecraft to be developed sooner.
Consider this: what if Scaled Composites were to get into the strategic fighter game? What if they were to go head-to-head against Lockheed's Skunk Works, and reduced the cost of stealth interceptor/fighter/bombers and spy planes to tens of millions per unit rather than a blllion per unit, and made them more efficient and faster to boot? Given their immense investment in conventional tooling and methodologies, I don't think they could change their ways and remain profitable... taxpayers would save money, we'd see more capable military aircraft, and as a side effect we would probably see variable geometry airfoils with the ability to reduce or even cancel out audible sonic booms become reality and over-land supersonic airliners become a practical reality.
The goal of a large government contractor is not to reduce costs (even if that is a requirement laid out in the RFQ/RFP), but to maximize net profits. Cost-cutting measures are always impractical until a new emerging player proves that it is possible.
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Space is VERY risky and unforgiving both because of the environmental extremes and because of the huge amounts of energy involved in getting there and getting back - so by nature any responsible program is sufficiently risk-averse that it does not choose lots of additional complexity and many more operations without very solid justification.
Which is another reason NOT to put a $10,000,000 payload on top of a $2,000,000 rocket and send it up in a single launch. Skylab was almost lost due to malfunctions of the Saturn that launched it.
The Skylab malfunction was with the Skylab module itself, not the Saturn V vehicle underneath it. "The station was damaged during launch when the micrometeoroid shield separated from the workshop and tore away, taking one of two main solar panel arrays with it and jamming the other one so that it could not deploy." -- http://en.wikipedia.org/wiki/S.... Your point holds though, just not the right example.
Why did you A/C this? It's dead on...