NASA Redesigning The Space Shuttle

ekarjala writes "To avoid wing damage from foam separation in the future, NASA is planning a redesign of the existing shuttle. Seems to me it is time to consider a new design rather than a redesign -- let's take the lessons we've learned and create a space craft for the 21st century rather than re-treading a 30-year-old design."

Comments

Why is it bad?

[aster_ken]

The way I see it, our space shuttles have done remarkable well in the past, and they continue to do remarkably well today.

Why change what works? Isn't that what we network administrators have said for years? If it ain't broke... don't fix it!

There are still "bugs" in the shuttle fleet, and NASA is creating "patches" for them. Someone please tell me what's horribly flawed about our existing shuttle fleet. What critical feature has yet to be added?

Re:Why is it bad?

[CtrlPhreak]

Cost per flight

The main idea of a redesign of the shuttle for the new century is that the current system is horribly inefficient and wasteful. Solid fuel boosters are yesterdays news, we need liquid fueled boosters or some new tech that can be controlled and possibly shut off if need be (current ones once lit go untill they're outa fuel that's it). The current external fuel tank (the big on in the middle of the system) just burns up in the atmosphere once it detatches, that's a waste of resources. The shuttle is also much larger than it needs to be, it has yet to consistantly run anywhere near capacity. When designed nasa was anticipating a much larger corporate demand for services of the space shuttle as well as a mandate that it would be able to go retrieve satilites in orbit. That extra space taken out would save lots of money. In short we need a lean mean shuttle machine that does what it needs to for a much lower operating cost than todays shuttle.

Re:Why is it bad?

[crow]

I expect that most of those advocating a replacement for the shuttle are doing so for several reasons, foremost being economics. A new system could conceivably be much cheaper to operate. And ignoring the economics, the act of developing a new system will help push technology forward and signal a renewed commitment to science and exploration.

Re:Why is it bad?

[cloak42]

I dunno. I think it would be smart to redesign what we've got now. After all, in the thirty years since the shuttle was designed, our knowledge of physics and aerodynamics has increased so much. We should really make sure that we can design something that can withstand the worst beating possible, not something that can barely make it through re-entry without losing bits and pieces.

Re:Why is it bad?

[RealityMogul]

artificial gravity

replicators

warp speed

photon torpedoes

holodecks

Re:Why is it bad?

[jrpascucci]

Efficiency - the shuttle was designed to be readily reusable and cheaper than throw-away rockets. It has not proven such. Safety - Things _are_ pretty safe, but not safe enough. Newer tech is significantly better. Smaller is safer, and easier to deal with: why the dual-use of sending people and stuff together? Send up 'stuff and supplies' in unmanned ships, send up 'people' in transports, and don't do both at the same time. Numbers - There are no longer enough shuttles to sustain an op-tempo that can help get real science done. Cheaper is better. And unmanned is cheaper and less risky. 4 unmanned launches to every manned launch should be a goal. What we need is more space _exploitation_, not exploration: we need to get a manufacturing capability out of the gravity well, using ambient energy. For instance, some very finely tuned instruments are best constructed in space. Eventually, we need to exploit other resources, further away from us. _THEN_, and only then, we can go to Mars.

Re:Why is it bad?

[aster_ken]

Most of what you just mentioned deals not with the shuttles themselves but with the launch systems. Yes, our launch system is *horrible* in terms of fuel efficiency (now I sound like I'm talking about cars) and the economics of it all. However, my question really deals with the shuttle itself.

Yes, if we took out a lot of that extra room then launches would cost less because the shuttles would weigh less. But why don't we just use that extra room instead? We could include additional large-scale experiments that would be too difficult to install in the space station (unless said experiments needed more than a week in space to complete). Why not actually try and retrieve some of the space garbage that has accumulated over the years? Yes, it's cost-prohibitive, but it needs to be done somehow.

I think I read on Slashdot somewhere that there's a laser in development to take care of that problem, though...

Re:Why is it bad?

[TomSawyer]

Wow, I was all for a redesign, but after reading your description the shuttle sounds like a big Space-SUV. It's rekindled my nationalist pride in it and brought a tear to my eye.

God Bless America!

Re:Why is it bad?

[rjh]

The following is an abridged and edited version of my full rant on the subject, available on my home page.

The following promises were made to us in the early days of the Shuttle: all these promises have failed to materialize.

• The Shuttle is not a `space truck'.
  
  It's more of a space Chevy pickup. When I think of trucks, I think of semis--things capable of carrying huge loads over long distances. The Saturn V rocket, the reliable workhorse of the Apollo program, could launch over 250,000 pounds to low Earth orbit or even put men on the moon. The Shuttle, by comparison, can only put 58,000 pounds into low Earth orbit and cannot reach higher orbits. Saturn V rockets made the 250,000-mile trip to the moon not once but several times, while the highest the Shuttle has ever gone is a meager 385 miles (335 nautical miles) during STS-82.
  
  In fact, the Shuttle is so sharply limited that it rarely deploys a satellite directly. Instead, the satellite is mounted to yet another rocket, carried to low orbit in the Shuttle cargo bay, and the second rocket then kicks it into proper orbit. I don't understand the logic: we launch the Shuttle into orbit so we can have astronauts risk life and limb ... launching another rocket into orbit?
• The Shuttle is not reusable.
  
  Endeavour cost $2.1 billion (source) and each launch costs $450 million (source) per mission. Most of that expense is taken up in refurbishing the Shuttle afterwards, where so much of the Shuttle is disassembled, inspected, replaced and reassembled that it's fair to declare it ``rebuilding'' instead of ``refurbishing''.
  
  More than this, not one single flight component of the Shuttle--not one!--has met its original flight rating. For example, the Shuttle's main engines were originally rated for 27,000 seconds of thrust (about 55 flights). After that time, the engines would have to be replaced. This design goal has not been met. As Nobel Laureate Richard Feynman wrote in the official report on the Challenger disaster, ``[t]he engine now requires very frequent maintenance and replacement of important parts, such as turbopumps, bearings, sheet metal housings, etc. ... [t]his is at most ten percent of the original specification.'' An engine with a life expectancy only a tenth what's expected may be replaceable and may be disposable, but it's not reusable.
• Twenty-six launches per year?
  
  Between maintenance, rebuilding and inspections, it's not uncommon for a given shuttle to only go up once a year. In Columbia's case, its final mission was its twenty--eighth flight in twenty--two years of service, and its second since 1999. We are nowhere near 26 launches per year per Shuttle; we aren't even close.
• Cheap?
  
  Hardly. Each launch costs $450 million. Even if the fleet were capable of 26 launches per shuttle per year, there's no way we could afford it. Instead of costing one hundred dollars to put a pound into orbit (as we were promised by NASA in the 1970s), it costs $7,750 ($450 million per flight, divided by 58,000 pounds of cargo). A 7,650%-cost overrun per flight can be read one and only one way: an engineering failure.
  
  By comparison, the Saturn V rocket could put a pound into orbit for $3,500, and a Russian Proton-M for $2,062.
  
  If the official NASA line of $450 million per flight isn't mind--boggling enough ... try dividing the amount spent on the Space Shuttle from its conception through 1993 by the total number of flights over that time period. You get an amortized flight cost of over one billion dollars (``Space Shuttle Value Open to Interpretation'', Aviation Week Forum, July 26 1993).
• Ten vehicles?
  
  The first shuttles cost $1.7 billion. Endeavour cost $2.1 billion

Re:Why is it bad?

[the darn]

but it's also lacking:

Spoiler

Type-R Sticker

Lowering Kit

Neon Paint

Re:Why is it bad?

[blahlemon]

Simply put, weight. The larger the experiment, the more weight, the more cost to put the shuttle into space, the higher the cost for the people funding the research.

The real question is why are we still using the shuttle? Sure it's one of the better designs for reentry into an atmosphere but there has got to be more efficient and cost effective ways of getting people and objects to space.

Re:Why is it bad?

[rjh]

It's a lousy design for getting into the atmosphere. One, the winged design adds absolutely nothing but weight. Sure, it makes certain polar orbits easier, but there's no scientific or military need for the Shuttle to launch into a polar orbit. Two, the winged design means that it lands like an airplane. This is great, except for the fact it lands at 220mph (a DC-3 lands at 130mph), its brakes have to bleed off three times as much kinetic energy as a DC-3's, the DC-3's brakes haven't been exposed to the blistering heat, chilling cold and annihilating vacuum of space, and if for some reason the landing gear fails to deploy the Shuttle, since it can't just punch the engines and make another pass, does a 220mph crash into the asphalt.

Sure. Great. The Shuttle is a great idea for re-entry, if you want to put your trust in a couple of thousand interconnected, interdependent systems, the failure of any one of which will totally doom you.

By comparison, a purely ballistic entry is easy. Do you have the right angle? The right velocity? Is your heat shield intact? Do your parachutes work? Great: go for it.

Re:Why is it bad?

[rjh]

No, I didn't miss the point with respect to the Proton-M. It puts 48,000 pounds of cargo into orbit at a cost of $2,000 per pound. The Shuttle puts 58,000 pounds into orbit at a cost of $7,700 per pound. That just means we're spending three times as much as we need to be when we could be buying our ELVs from Russia.

I agree that a totally different launch solution is needed. But the Proton-M is worth noting and comparing the Shuttle to, if only to show how incredibly, mind-bogglingly atrocious a launch vehicle the Shuttle is. It costs three times as much and has a one-in-fifty chance of snuffing out seven human lives? No thanks.

Re:Why is it bad?

[stevesliva]

I believe you somewhat blur the distincion between payload capability and "cargo" capability. It'd be neat if the Proton could launch combined payload of a 165,000-pound shuttle (yes, a ridiculously huge crew return vehicle, but still payload) and a 58,000lb "cargo," but I don't believe that there are any other current systems that can launch a few hundred tons into orbit. Yes, the fact that the shuttle reuses the three main engines blurs the payload/launch system boundary, but they are still reusable. Certainly the Soyuz rocket payload capability of about 12,000 pounds includes the crew capsule! You campare the shuttle launch system to the Saturn V. Good comparison... every shuttle launch (except the last) is like launching Skylab and getting it back again in two weeks. Yeah, I can see why you might consider than inefficient. ;) But Skylab only weighed 78,000 pounds, so maybe two Skylabs is a better number.

Misleading /. title

[elliotj]

Um, I may be the only one to actually READ the linked article, but it really doesn't say that they're redesigning the Space Shuttle. They're considering a new design for the part that is supposedly responsible for causing the crash. To say that they're redesigning the shuttle I think is overstating things.

Re:Misleading /. title

[stefanlasiewski]

Are those air tunnels not capable of producing the amount of friction / heat necessary to simulate re-entry?

No. When the Columbia broke up, it was travelling at "12,500 mph (Mach 18.3) at an altitude of 207,135ft".

It's probably possible build a wind tunnel to simulate a 12,500 MPH wind and simulate the atmosphere at 207,000 feet for an object as big as the orbiter, but it will be very expensive and difficult to build in our political climate.

Re:Misleading /. title

[Alsee]

build a wind tunnel to simulate a 12,500 MPH wind and simulate the atmosphere at 207,000 feet for an object as big as the orbiter, but it will be very expensive and difficult to build in our political climate.

However it would be cheap and easy to build in a different political climate. Of course it would have to be a political climate that runs on soy-based biodegradeable pixie dust. :)

-

Turn it over to the private sector...

[danbeck]

There is no magical autocad plugin that just redesigns the shuttle system. Just because we all want to see some sort of B5 or Star Trek design hurtling up into space, holodeck and all, doesn't make it worth while to scrap an entire group of shuttles, their support systems and the related industries behind it.

In any case, if you want to do something about the sad state of the space program, push for giving the private sector the ability to do what NASA does. There is where your real innovation will take place.

Takes a long time

[gi-tux]

You have to remember that building a new system takes a lot of time. Marshall SFC is already working on a space plane but it isn't scheduled to be ready for some number of years. I am including a quote from the Huntsville Times below:

Former U.S. Sen. John Glenn, who flew into space on a shuttle mission in 1998 and was the first American to orbit the Earth in a 1962 Mercury mission, told The Times the space plane might be "too expensive, too complex and probably too late to fit the station's needs."

This was from an article concerning what to use to replace the shuttles for the needs of ISS. In another article he also stated.

Glenn compared the situation with the space shuttle to the airline system.

"Airplanes fall out of the sky, and you don't stop flying," Glenn said.

BTW, in one of the two articles quoted above John Glenn proposed a re-entry sphere that is heat shielded and equiped with parachutes and oxygen. This could splash-down in the earth's oceans for recovery. This would be used for emergency and medical evacuation from the ISS. Sounds logical to me.

Also John Glenn has several times stated that the science is important and that the ISS needs to got to full staffing of 6 or 7 ASAP. The re-entry sphere would allow that to happen rapidly and is likely why he supports that idea.

Disclaimer : I do live in the Huntsville area, but I am not in anyway affliated with Marshall SFC or NASA.

Re:Takes a long time

[gi-tux]

But John Glenn is/was an astronaut and he understands that those guys and gals are explorers. Most would probably go for the ride even if they knew they wouldn't come back and they all go knowing that they might not come back.

If they would launch me in a shuttle tomorrow, I would go happily. I would bet that a large number of /. readers would agree to go also (hint that might be a good /. poll question).

Compare these explorers with explorers of times past. Columbus lost large numbers of his crew, as did Coronado and DeSoto. Anytime people have gone into an unknown frontier large numbers have not returned. The space programs of the USA and the USSR (now Russia) have lost several people, but the loses have been much less than any other exploration in history.

Now don't think that I don't grieve for the lost heros, because I do. I wish that we could explore space with no loose of life.

Junk the Shuttle -- and ISS while you're at it.

[Anonymous Coward]

I'm sure many will disagree, but the cost of the shuttle program is horrendous, and NASA's insistence on using it has led to some cataclysmically stupid decisions. One example: the ISS (which is an utter joke compared to Skylab or Mir) was placed into a rapidly-decaying orbit not because that was a good idea (it isn't) but because the shuttle could get there.

Most of the satellites that are "launched" by the shuttle suffer from the design constraint that they have to fit into the friggin' bay AND have room for the accompanying boosters that will put them into their real orbit once the shuttle lets them out. Again, the shuttle can't go high enough for real deployment.

The idea of capturing and reparing satellites is inherently absurd; most aren't where the shuttle can get 'em and the total cost of the program utterly dwarfs the expense that would have been incurred had they said of the Hubble "Well, we screwed it up...build another one and get it right this time."

The safety record sucks. After Challenger Richard Feynman put the probability of a fatal accident at one in fifty. So far, NASA's on the money and the nature of the shuttle is such that if someone dies, everybody dies.

Lest I be misunderstood, I understand the romantic and scientific appeal of manned space flight, of the visceral sense of satisfaction we can have as a species when we look up to the skies and say "We live there." I'm a strong proponent of that. I also recognize the complaints that the money spent on that is money not spent on (feeding the hungry, housing the homeless, inoculating the sick, fill in your pet cause). The manned space program is hellishly uneconomical and a great deal of that can be laid at the feet of the shuttle program.

It's a white elephant without a mission, a bastard child of a spacecraft and an airplane which like most gadgets that try to do two fundamentally different things does neither well. Its payload capacity compared to heavy-lift rockets is a joke, it's barely capable of crawling out of the atmosphere, it's presented a tremendous constraint to the rest of the space program by forcing many missions to be less than they could have been in order to be shuttle-doable, and it bears repeating that every fifty flights it kills everyone on board.

It's time to ground the shuttle fleet permanently. Space isn't going anywhere. Stop pouring the hundreds of millions of dollars into the shuttle program and pour them into a new design effort. Scrap the silly "space-plane" concept and develop a family of lifters and craft that _can_ be used for many things but don't back NASA into a corner that forces them to use it for all missions. Make crew safety an inherent feature (recognizing that there are tradeoffs and that getting out of the gravity well is a fundamentally dangerous activity). Stop throwing good money after bad on that ISS as well, and use the collective resources of the two programs to start over. It's not true that the second design is always better than the first (see again ISS and Mir/Skylab) but you're wise to play those odds.

Let's do it over. And do it right.

obvious

[Thomas A. Anderson]

I think the reason they are fixing the old design rather than using a new one is obvious - money and commitment.

First the money part: while in the long run it will cost more to keep the old fleet alive rather than build new, cheaper shuttles, the short term investment is much lower for the redesign. Especially in this day and age with a monster defecit.

Second, commitment. We have a manned space station up there. On that (this is a guess) will not stand up well to be un-manned. Yes, we have russian rockets we can use, but nasa isn't too happy about not having a backup method to get people up/down. A new shuttle would take 5-10 years to design, build, and test. By that time, all the money invested in the space station would be a waste it it was un-manned for so long.

just my 2 cents.

Sure... but 1)time and 2)$$$

[delorean]

Alright, sounds great. I'd love to see a better space craft (and I have vested interests in space flight).

But let's look at something:

Time

1. It would take minimum of 10 years to design, build, and test a working model.
2. We've got the ISS flying right now that needs service and crew changes-- and more often than the Russian Soyuz can provide. While I'm on the Soyuz-- their last flight wasn't so hot either. That was a new model, too. Did you know it takes 18 mos. to build a Soyuz capsule? Did you know they barely have enough money and crew to meet the six month demand for the ISS? Do you trust the Russians to go drum up people from the unemployment line to ramp up production? Do you... ah, nevermind.
3. Space is not easy or safe. The fact that we've only lost three crews in forty years of space flight is totally remarkable! It is not a safe environment. Tito and the other dude who flew on the Soyuz took their life into their own hands-- and hell I would do the same in a heartbeat! But it is not safe. It is extremeley dangerous and every astronaut knows that. Citizens forget that.

Money

1. It will take billions of dollars to pick one of the many designs for the next orbital plan/vehicle, build and test ONE.
2. We also face increased spending on defense, security, and welfare. (Damn terrorists, criminals, lazybones, and old folks) Which one will you cut?

People see NASA's record and watch Enterprise every week and think it's an easy thing. It is not!

I TOTALLY agree that we do need a new vehicle. But we can't just mothball the Shuttle and stick 'em in museums. They have to be toughened up and fly for the next ten years until the new vehicle is ready. I REALLY want a new vehicle now! But I am fatally realistic: the shuttle will be permanently grounded, the borrowcrats will cut NASA some more causing the space plane to take too long, and the ISS will probably do the SpaceLab thing.

Give the entrepeneurs a chance

[Rxke]

NASA could also hire launch hardware, instead of building it by themselves. it would give a boost to the market, the know they have a customer with certain needs, and they will make sure it is cost-effective. If NASA put up an 'ad' saying: we ned a man rated launcher, for at least 4 launches a year, an unmanned launcher, capacity XXXX et.c., i'm sure SOMEONE would come up with sumtin useful. If they did that, maybe Russia's behemoth ENERGYA booster would become used again, it was awesome, but flew only once, there was no market for it... Also, the small fishes could benefit, if NASA prepaid them for their first several small launches, they could literally go far. And NASA could stick to developping sciencemodules, habitats et.c. everybody wins. (ok; i know, oversiplicized; but hey, i've been thru a long and boring day, so my brainzz are kinda rusty)

It's not bad.

[s0l0m0n]

They aren't redesigning the shuttle itself. They are redesigning the launch system, to prevent a similar accident ot the last one.

The over all effect on the shuttle itself is nil, as far as I can tell from the article.

Re:Flip side

[cgenman]

Many of the kinks and problems have been ironed out.

Evidence indicates that several kinks and problems remain.

Think of it in terms of software, which do you think works better: version 1.0 or version 9?

In terms of software, we're on space shuttle version 1.99.99.99. We have tremendously smothed the wrinkles in an existing design, but the specifications at creation and the current necessary specifications and available technologies are radically different. This is not as simple as saving space and weight by using LCD moniters instead of CRT's... Could shuttle subsystems communicate more efficiently over 802.11b? Should liquid, nuclear, or ElectroMagnetic accelerants be used in place of solid fuel boosters? Should the shuttle carry less weight in order to carry payload to a higher orbit? Escape pod?

For crying out loud NASA engineers still scour Ebay looking for parts to keep the shuttle fleet up in the air. Isn't it about time we put a PowerPC or a P4 up in the air?

Maturity of a technology involves both incremental and radical redesigns... Such a process brought Win95, NT, XP, and someday a mature Windows OS. Mac OS9 was a very mature OS (based off of an OS7 lineage), but it was just too old and, in some ways, too mature to jerry rig preemptive multitasking into it.

Now that the shuttle has followed its natural lifecycle we are in the enviable position of looking at its role in the larger world and saying what is it being used for and, using our experience, how can we better design it to serve that need?

I am not saying a new design is a bad idea, just that we have a significant investment in our current shuttle and thats why it has been around so long.

Sadly, pouring good money after bad isn't going to help our prospects long-term. The costs are sunk, and can't be recouped. If designing and implementing a new shuttle costs 50 billion dollars, but the per-launch costs can be reduced from 450 million to 100 million, then assuming an acellerated launch schedule of one flight every two weeks (the original estimates for the original shuttle), we will have a net financial gain after less than 5 years. And besides the financial gain, who knows what the value of the scientific gain by having a shuttle capable of such frequent voyages.

(Yes the above numbers are somewhat spurious, but they also don't take into account the 2-4 billion dollars per current shuttle with a 50 flight lifespan, the cost of investigation of a shuttle disaster, the potential for reduced personnel in a more modern system, etc)

Re:Flip side

[blahlemon]

Just a note on the escape pod idea:

Even if there *was* an escape pod it would be useless in a reentry situation, at least with the way we do reentries right now. The number and strength of the forces acting on the shuttle during the reentry phase make escape pods high impractical if not impossible. Besides, there probably wouldn't be enough time to get into an escape vehicle.

Suggestion

[schnits0r]

If they are worried about foam, why don't they use Aerogel instead? It's lighter, heat resistant and transparent.

Maybe Rockets aren't the answer

[garyebickford]

Maybe your old monitor can take you into space. (Here's About.com's take, a bit popsci.) I thought this was bogus until I saw This mouse flying in a lifter - including RealVideo.

Perhaps we have a workable alternative to rockets available. Rockets are a terrifically inefficient way to get, essentially, a 1 to 8 hour drive straight up. In order to do that we have to spit 100 times our mass out the back. That's a lot of commotion and expense and danger. If the tech shown here actually works, it might make the whole concept of rockets obsolete.

It seems this guy Townsend Brown patented what is now mostly called "ElectroKinetic Drive" back in the late 1950's. It was immediately ignored. But it seems to work quite well, even in a vacuum (I'm still a bit skeptical on this point - IMHO the vacuum test I saw pics of on this site was not sufficient.) Lift capability appears to be on the order of 1 gram per watt, perhaps better than that with good design.

At this point, there are almost 200 successful experimenters worldwide, flying lifters using the 'asymmetrical capacitor'. In Japan they have one over 5 meters wide, flying 15 meters in the air. (one of the photos also shows some cool sci-fi looking high voltage equipment below it.)

All of these devices so far have been powered by external high voltage sources, mostly from old PC monitors. I'm not a HW geek, but I figure if you can build a HV system that generates 15KV to 50KV, and enough continuous power to produce 2.5 or more watts per gram, you could build a completely self-sustained lifter.

Of course, I wanna be the first to do this, so I'm not gonna post it on Slashdot. No, really, I hope that lots of people start experimenting with this, and publish their results using a GPL-type approach to patents, so the major tech is bound up in open hardware licenses. This will prevent those who want to own this tech from patenting every nut and bolt and preventing us from building our own. For example, using attitude sensors and a crossover network to vary lift on different sides and maintain attitude and generate horizontal velocity.

Here and Here are some thrust calculations. The latter has a calculator to design your own. If you build one big enough for me, please give me a ride!

Also, if you follow this up, you'll find lots of interesting and downright spooky connections to UFO's, the Lockheed Stealth Blimp (what was that thing that floated over Phoenix in 1997?)

Re:A flaw in your reasoning

[Phronesis]

No. My argument is to keep flying shuttles and keep killing astronauts at a rate of about one crew per decade. That would leave a lot more money for research. As for astronauts, they have known the risks all along. NASA and the National Academy of Science have reviewed and published the probabilistic risk assessments all along and these numbers have not scared astronauts away.

After the last shuttle crashes, we could ask whether the research conducted on the shuttle was more productive in saving lives per dollar spent than terrestrial research or that conducted on unmanned spacecraft and decide on that basis whether to build another fleet.

Hermes anyone?

[theolein]

Although this post is about a French craft, and everyone knows how well the Americans and the French get on ;), why the hell doesn't someone use some common sense and use a design that is not some overloaded flying brick.

Cut space efforts into two parts:
1.Launching payloads. Ariane 5, Deltas etc can and do this very well. These launchers are designed for lifting satellites, and other heavy payloads into geostationary orbit and beyond.
2.Launching humans. A small purpose designed craft like the Hermes, that can return to earth like the shuttle, AND be launched on top of a heavy lifter such as Ariane 5 is far more practical than the shuttle could be.

But perhaps Americans dislike the idea too much that it's originally French, and perhaps the French can't afford to pay for this anymore.