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Will The Next Generation of Spacecraft Land In the Water?

Zonk posted more than 6 years ago | from the splashdown-for-the-future dept.

NASA 318

Reservoir Hill writes "Work is progressing on the design of the new Orion Crew Exploration Vehicle (CEV), the next generation of NASA spacecraft that will take humans to the International Space Station, back to the Moon, and hopefully on to Mars. One major question about the spacecraft has yet to be answered. On returning to Earth, should the CEV land in water or on terra firma? After initial studies, the first assessment by NASA and the contractor for the CEV, Lockheed Martin, was that landing on land was preferred in terms of total life cycle costs for the vehicles. Getting the CEV light enough for the Ares rockets to be able to launch it, and therefore eliminating the 1500 lb airbags for landing has its appeal. A splashdown in water seems to be favored."

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SLASHDOT SUX0RZ (-1, Flamebait)

Anonymous Coward | more than 6 years ago | (#21699748)

_0_
\''\
'=o='
.|!|
.| |
will the next generation of goatse land in water? [goatse.ch]

Re:SLASHDOT SUX0RZ (-1, Troll)

Anonymous Coward | more than 6 years ago | (#21700514)

Flamebait? Get a fucking clue mods. The above was obviously trolling, not flamebait. You'll pay for that mistake in meta-mod. To think of the sheer amount of brilliance, cunning and luck that went into successfully obtaining a first post with the above only to have some dimwit mod mark it incorrectly.... it's sickening.

At least mod this post down correctly. And somebody should mod up the parent so he can be properly modded down again as troll, not flamebait.

Thought about something like this (3, Interesting)

pkadd (1203286) | more than 6 years ago | (#21699750)

Something i used to think of as a kid was: How about using the propulsion you get from the water for initial thrust of the spacecraft? Sort of like the effect you get from releasing a bottle of air under water, couldn't that be utilized in a cheap way of getting that initial upwards thrust, or would it be too cumbersome to make a vessel that is light enhough for it to actually float?

Re:Thought about something like this (2, Insightful)

427_ci_505 (1009677) | more than 6 years ago | (#21699774)

I'd imagine that would be insanely hard to control even if it was possible.

Re:Thought about something like this (5, Funny)

pkadd (1203286) | more than 6 years ago | (#21699856)

Well, when people say something like "hard to control" i thing this: 1% chance of it actually working as intended 99% chance of it failing horribly 100% chance of it still looking incredibly awesome :D

Re:Thought about something like this (1, Funny)

Anonymous Coward | more than 6 years ago | (#21700512)

So, you're a glass half-full type of a guy?

Re:Thought about something like this (3, Funny)

Anonymous Coward | more than 6 years ago | (#21700560)

Seeing as how this is slashdot, he's probably either a glass twice as large as needed type of guy or a guy with a diminutive problem.

Re:Thought about something like this (3, Funny)

Shakrai (717556) | more than 6 years ago | (#21700550)

1% chance of it actually working as intended 99% chance of it failing horribly 100% chance of it still looking incredibly awesome

Adam [discovery.com] ? Is that you?

Re:Thought about something like this (2, Informative)

gentimjs (930934) | more than 6 years ago | (#21699800)

You'd spend more energy getting the buoyant "rocket" down deep underwater and keeping it there, and then it probably wouldnt 'bound' more then a few feet out of the water. Check out a video of a submarine doing an "emergency surface" then consider if it would help get the submarine into space. Interesting idea, but No-go.

Re:Thought about something like this (2, Interesting)

sholden (12227) | more than 6 years ago | (#21700220)

Yes you wouldn't get enough velocity to make a it worthwhile, but spending more energy on the ground (well under the water...) doesn't matter. If you could come up with a way to use ten times as much fuel (for a given total weight) to launch a rocket than the standard approach, but have that fuel be used on the ground and not be lifted by the rocket it would be used in a flash (it's what a rail gun launch would be after all) - assuming you manage to not turn the people inside to smears on the wall...

Re:Thought about something like this (4, Interesting)

IdeaMan (216340) | more than 6 years ago | (#21700646)

Actually the submersion idea is brilliant. The piece missing is the launch tube.
Build a 30 foot diameter tube 2 miles deep, with a piston on the bottom. Put brakes on the piston that will limit the acceleration down to about 5G. Empty the piston of water, lower spacecraft onto piston, when you launch just let the piston rise. The thousands of PSI of water pressure should give the spacecraft a significant amount of speed by the time it reaches the surface, light off rocket at a higher altitude than normal so the nozzle can be optimized for a higher altitude burn. I'll work on the math for this.

Re:Thought about something like this (1)

zaunuz (624853) | more than 6 years ago | (#21700020)

I find your sig both impressive and disturbing at the same time

Re:Thought about something like this (0)

Anonymous Coward | more than 6 years ago | (#21700350)

That initial v_0 would have no impact. You are talking about being able to add a couple of m/s to something that needs to be going Mach 25 to reach orbit.

This doesn't mean that sea launching vehicles is a bad idea. There are several different types of sea launch vehicles currently in operation. Being able to launch at any latitude you want is very convenient. And sea launches will probably be the preferred method of launch for future ultra-heavy vehicles that would be too difficult to move by any means other than the seas (something similar to the 500 ton Sea Dragon).

Re:Thought about something like this (1, Informative)

Anonymous Coward | more than 6 years ago | (#21700788)

There have been serious studies into this idea for decades, generally involving a giant "gun barrel" submerged in water. Pump the water out, put the rocket in, let water in from the bottom to push the rocket out. Unfortunately, the NASA site with all the cool and futuristic science has been taken down (no doubt because Al Quaeoeida could build their own terrorist space elevator if they read about it on the web).

Here's a link to a really old (1963) article on a variant of the concept: http://www.time.com/time/magazine/article/0,9171,829711,00.html [time.com]

Simple Answer (2, Insightful)

gentimjs (930934) | more than 6 years ago | (#21699762)

Re: "Getting the CEV light enough for the Ares rockets to be able to launch it," .. the solution is simple .. buy/license/whatever the Energiya booster from the ruskies instead, and you'll have much more weight to play with.... OH sorry, I forgot, the Energiya isnt build in the correct congressional district... my bad.

Re:Simple Answer (1)

DerekLyons (302214) | more than 6 years ago | (#21700138)

No, what you forgot is that there isn't any such thing as an Energiya booster. The Energiya was scrapped years and years ago - and never was fully operational in the first place.

Re:Simple Answer (4, Informative)

ianare (1132971) | more than 6 years ago | (#21700152)

The planned Ares V has a mass to LEO [wikipedia.org] of 130,000 kg, the energia has 'only' 88,000 kg, so the solution isn't that simple. Besides, any weight savings on any system is obviously an advantage when the cost per kg is so high.

Re:Simple Answer (1)

ianare (1132971) | more than 6 years ago | (#21700284)

on further reading, one of the engines used in the Atlas rockets is in fact the RD-180 [wikipedia.org] , developed and built by the Russians.

Re:Simple Answer (0, Offtopic)

sm62704 (957197) | more than 6 years ago | (#21700212)

Don't they still have plans for the Saturn [wikipedia.org] laying around somewhere? That was one bigassed machine capable of hauling a lot of real heavy stuff up there. The only two Saturns I ever heard of blowing up were the Apollo 7, which wasn't the rocket itself but the crew capsule catching fire, and the Apollo 13 that they actually got all th eastronauts home in one piece despite its mishaps.

The Apollo program that sent men to the moon had a much better safety record than the Shuttle, which lost two crews, one on takeoff and another on re-entry.

-mcgrew

Re:Simple Answer (0)

etijburg (684177) | more than 6 years ago | (#21700292)

No they had to distroy the plan for the saturn to be allow to build the space shuttle. I know this sounds stupid but it is the way it worked out.

Re:Simple Answer (1)

Aglassis (10161) | more than 6 years ago | (#21700410)

It sounds stupid because this is an urban myth. Perhaps the next time you think something 'sounds stupid' you will instead google [google.com] it before you spout off.

Re:Simple Answer (1)

timster (32400) | more than 6 years ago | (#21700542)

Urban legend. The plans for the Saturn V are just fine, but they are completely useless now. For one the rocket is ridiculously obsolete in many ways; for another the parts it was made with have been out of production for decades.

Re:Simple Answer (1)

sm62704 (957197) | more than 6 years ago | (#21700626)

Obsolete how? It worked then, how does being "obsolete" make it not work? And as to parts availability, did they really build that thing from off the shelf parts? I mean, aside from stuff like coper tubing and so forth.

I don't understand how we could have built something in 1967 that we couldn't still build forty years later.

Re:Simple Answer (0)

Anonymous Coward | more than 6 years ago | (#21700444)

Get this into your skull. The Saturn V was an inefficient launcher. For less weight and size the Ares V will be simpler and place 50% more mass on the way to the moon.

Re:Simple Answer (1)

SWCommand (983311) | more than 6 years ago | (#21700448)

First off the problems that you mentioned were not due to any failures of the Saturn V. They are all due to command module problems. Second the Saturn V was launched a lot less then the Shuttle, of course it will have a better record. Plus the launch loss of the shuttle was due to a solid rocket booster failure not the shuttle. The second one was due to failure of the shuttle proper.

The "Me Too!" launcher (0)

Anonymous Coward | more than 6 years ago | (#21700334)

The Energia has to be the most laughably inefficient launcher ever created. Can you see that the Ruskies are in no hurry to launch it again. Putting the Russians in the critical path or any project is unwise if you consider the ISS experience.

Re:Simple Answer (3, Insightful)

p0tat03 (985078) | more than 6 years ago | (#21700442)

There are some very good reasons for building an all-American rocket beyond mere politics. It has everything to do with developing domestic expertise in the field, and encouraging R&D in the country for these technologies, which can only serve as a foundation for developing even more.

Beyond what the other posters have mentioned, brute forcing the problem is also rarely a good solution. Instead of spending tens of million each launch to lift a huge, heavy spacecraft into orbit, its weight should be optimized, both for the sake of proper engineering and for the sake of cost cutting. I won't presume to know the specific technical difficulties of a project as complicated as the CEV, but there's a balance between more lift power and reducing spacecraft weight.

Stupid Answer Re:Simple Answer (2, Insightful)

Brett Buck (811747) | more than 6 years ago | (#21700588)

Oh, good lord. What Energiya would that be? The prototypes corroding away somewhere, never having been launched? There is no such thing as an Energiya, aside from old photos with a Buran attached, and some blueprints. You'd do better to start from scratch than with Energiya plans.

      And of course, you overlook the many domestic alternatives that *actually exist*. Like EELVs (Delta and Atlas). Or those that could be restarted since they just quite making them a few years ago (Titan IV - roughly equivalent to a Saturn 1B).

        Brett

Re:Stupid Answer Re:Simple Answer (1)

Criton (605617) | more than 6 years ago | (#21700696)

The delta IV can scale up to 50T on existing tooling so it should be the crew launch vehcile. It can lift 35T using just regen RS68s and GEM60 strapon boosters something that can fly in two years from the word go.

A stupid simple answer (2, Interesting)

Criton (605617) | more than 6 years ago | (#21700660)

A brain dead simple answer would be to use direct launcher http://www.directlauncher.com/ [directlauncher.com] as the crew launch vehicle. Direct launcher makes use of existing four segment srbs and existing RS68s plus it lifts 50tons in it's most basic form vs 25 for Ares I mass problem solved and 2 billion saved on Constellation. The only answer I can think of right now is the fire Griffin it's the only way to save the project. That or kill Orion outright and give all the budget to COTS type programs. I see no hardware for Orion yet but spacex is now building and testing falcon 9 and Dragon.

Re:Simple Answer (2, Insightful)

GreggBz (777373) | more than 6 years ago | (#21700722)

How is this modded insightful? Just because it poo-poos America? The Energiya is not in production. We don't know if the larger (theoretical) models are worth anything. They may be based on prior proven technology but so is the Ares. There are certain to be major engineering differences (fuel, electronics, avionitcs) that we don't have the support infrastructure for. And lastly, even though NASA has a pretty good history of cooperating with foreign agencies in space, what is wrong with building something ourselves, giving Americans jobs and bolstering our economy (and those of foreign contractors) in the name of space exploration?

I understand it's not all black and white, and that there is a big fat contract waiting for Lockheed Martin, but I can't see contracting a big rocket from the Russians as anything but more trouble. At least if we fail, we are the only ones to blame.

If a big Energiya was ready to go, reliable and we had the support systems to deal with it, you'd have a point.

Water or land? (4, Informative)

GenKreton (884088) | more than 6 years ago | (#21699804)

As someone who worked partially on the CEV, it has been decided. it is in the requirements that Lockheed Martin furnish a vehicle that is capable of both. One of the design limitations now is that it must actually be stable in swells of up to 14 feet, which are not uncommon in the cold North Atlantic - emergency abort scenarios land all launches there during early lift-off stages. There are huge problems with ill-effects of ocean landings for crews and they really are looking to avoid it, but even with parachute and pillow systems, they are looking at potential damage,

Re:Water or land? (1)

zgregoryg (1061612) | more than 6 years ago | (#21699910)

The Russians have been landing on land for decades. I always thought it was because water landings were too inconvenient for them and that water was best. I mean how could you not based on who actually achieved Man on the Moon? Now we find that maybe the Russians were smarter and we just luckier?

Re:Water or land? (1)

plague3106 (71849) | more than 6 years ago | (#21700438)

Well they also have a lot more land to use as the target area :-)

Re:Water or land? (1)

Moridineas (213502) | more than 6 years ago | (#21700556)

What's your point? We've done both, they've done both. How is it a question of "smarter" and "luckier."

You don' repeatedly get to the moon on luck alone.

Re:Water or land? (1)

DraconPern (521756) | more than 6 years ago | (#21700004)

Since the craft is coming down fairly fast, isn't the impact of landing on water or land about the same?

Re:Water or land? (1, Informative)

Anonymous Coward | more than 6 years ago | (#21700040)

You can lead into a water landing by piercing the surface before the bulk of the craft impacts, breaking surface tension and considerable pillowing the landing.

Re: Water or land? (1)

mi (197448) | more than 6 years ago | (#21700022)

An excellent question of terminology. The current generation of spacecraft waters safely on land. Will the next one be able to water on water?

Re:Water or land? (1)

mollymoo (202721) | more than 6 years ago | (#21700300)

As someone who worked partially on the CEV, it has been decided. it is in the requirements that Lockheed Martin furnish a vehicle that is capable of both.

The capability to be able to do both has been decided; the decision as to which they will preferably use on an ongoing basis has not been decided, and that is what TFA is about.

Re:Water or land? (0, Troll)

Criton (605617) | more than 6 years ago | (#21700376)

Ok so why not ditch the god awful ares I booster for direct launcher then all you mass troubles will disappear. Also you will no longer need the J2X for anything as you would now only have two ground starting RS68s and can use the much more efficient RL60 for the EDS engines . I wonder how many billions this will save I do know it will cut 3 years of development times and produce a far safer spacecraft. Direct also makes use of proven 4 segment SRBs the crew launch vehicle and cargo vehicle now have many common parts vs almost non with ares I and V Failure to much such simple an obvious changes to ESAS is why I've pretty much given up on Constellation. This stubbornness is going to doom the project or at the very least cost the lives of a crew. I now placed most of my fate in a continued US manned space program with new players like spacex.

Re:Water or land? (1)

zsouthboy (1136757) | more than 6 years ago | (#21700498)

I am interested in your ideas and would like to subscribe to your newsletter.

Re:Water or land? Or fluffy soft snow? (0)

Anonymous Coward | more than 6 years ago | (#21700706)

I'm sure that after further evaluation they will realise that fluffy soft snow is the safest option. It would be silly to decide on deadly hard terra firma or second worst water, unless some government torpedos the Bali conference and makes snow all but dissapear from the planet. But that would be a silly thought.

> As someone who worked partially on the CEV, it has been decided.

What? What!
What is the USA planning?
What in the hot hell is the USA planning?
Ooh, dear humanity...

Theyy could always ask Paul Revere ... (4, Insightful)

trolltalk.com (1108067) | more than 6 years ago | (#21699806)

"One if by land, two if by sea ..."

Seriously, why not just do the moon mission, then pick up the landing bags as the ISS on the way home. Better yet, why not have a specialized vehicle just for orbit-to-moon-and-back, and transfer to a special-use re-entry vehicle at the ISS?

Re:Theyy could always ask Paul Revere ... (4, Insightful)

2short (466733) | more than 6 years ago | (#21699902)

Why involve the ISS (besides politics)?

Just put whatever you want to rendezvous with in whatever orbit is convenient, it won't go anywhere.

Re:Theyy could always ask Paul Revere ... (1)

moderatorrater (1095745) | more than 6 years ago | (#21700218)

Because it's a lot easier to find the ISS than it is to find a package you sent randomly flying around the earth.

Re:Theyy could always ask Paul Revere ... (4, Informative)

2short (466733) | more than 6 years ago | (#21700328)

Yes, sending it "randomly flying" is exactly what I proposed.

You put the package in whatever orbit is convenient (as opposed to the ISS, which isn't convenient), and you know its position as surely as you know that of the ISS, or any other sattelite. Space navigation doesn't involve any "finding", ever.

Re:Theyy could always ask Paul Revere ... (1)

B3ryllium (571199) | more than 6 years ago | (#21700694)

Space navigation *does* involve having boosters to prevent orbital decay, though - and guess what the ISS has? Boosters! Go figure.

Re:Theyy could always ask Paul Revere ... (0)

Anonymous Coward | more than 6 years ago | (#21700408)

. . . it won't go anywhere.

Until China shoots it down. [slashdot.org]

Re:Theyy could always ask Paul Revere ... (2, Insightful)

DerekLyons (302214) | more than 6 years ago | (#21700208)

Seriously, why not just do the moon mission, then pick up the landing bags as the ISS on the way home.

Because that would actually _increase_ the mass boosted towards the moon by a factor of a thousand of more. (It takes a lot of fuel to brake into Earth orbit, and yet more to change orbital planes to match up with the ISS.)
 
The next poster posited simply leaving the required module in a convenient orbit not at the ISS. This is a little better as it only requires increasing the mass boosted towards the moon by a factor of seven hundred or so.

Re:Theyy could always ask Paul Revere ... (1)

2short (466733) | more than 6 years ago | (#21700640)

Based on my understanding, you're going to "break into earth orbit" upon return anyway; it's a matter of whether you keep breaking and re-enter, or orbit a bit first.

Now, matching orbits to rendezvous with a previously deployed package may be a different matter; It will be no problem if everything goes perfectly. but if that rendezvous is required in order to re-enter, you're going to want a healthy safety margin on your ability to do it, and that margin will consist of fuel. Probably enough to weigh more than whatever you're leaving in earth orbit.

The key, I think is that almost all the thrust for getting to the moon gets used in getting from the ground to low earth orbit. Any weight savings from anything you do after that won't make much difference.

Of course, we could achieve massive savings, and skip re-entry problems entirely by leaving behind the pointless humans...

Re:Theyy could always ask Paul Revere ... (1)

PieSquared (867490) | more than 6 years ago | (#21700250)

As someone already pointed out involving the ISS would be a waste.

More to the point though... there are already 3 parts being assembled in space IIRC. The Orion capsule goes up alone, where it attaches to the "earth departure stage," the rocket it needs to leave earth orbit, and the new lunar lander (Altair, named yesterday). But taking airbags up separately.... wouldn't be easy. It would mean a (or an additional?) zero-g EVA to insure each bag attached properly. Not to mention it costs quite a bit of money to take stuff into orbit even separately.

No, the correct answer to this question is to either decide landing by sea is fine (and roll out the NASA naval branch again...) or to build a bigger rocket. Or, hell, use the ares IV or V instead of the ares I. They use the bigger once to launch the earth departure stage, and they could handle a bigger Orion.

Disclaimer: all I know of the Orion system and the return to the moon I learned from wikipedia and the NASA website.

Re:Theyy could always ask Paul Revere ... (0)

Anonymous Coward | more than 6 years ago | (#21700342)

During a lunar mission the CEV would not enter earth orbit on the way home. They would be going too fast and they don't want to lug enough extra fuel all the way to the moon and back to shed that all that velocity. They would make an Apollo style return where they come down a direct reentry corridor from the moon. So docking with ISS (or anything else in earth orbit) on the way home is not an option.

This is why the heat shields for the CEV are more difficult to make than those for a similar spacecraft that only travels to LEO, they hit the atmosphere going much faster and all that energy gets converted to heat.

Re:Theyy could always ask Paul Revere ... (0)

Anonymous Coward | more than 6 years ago | (#21700352)

They definitely found evidence of water on both the moon (ice) and mars (mud) ... We should definitely go for water landing!

It's still legal to think. - Patte De Lapin

Re:Theyy could always ask Paul Revere ... (5, Informative)

delta407 (518868) | more than 6 years ago | (#21700372)

Why not pick up the landing gear on the way back? Let's investigate.

Recall: Apollo's flight plan was an initial burn to get into earth orbit, another burn to leave orbit on course for the moon (trans-lunar injection), another burn to get in orbit of the moon, and another burn to leave orbit on course for earth (trans-earth injection). That's it. They didn't return to orbit after leaving the moon. They left the moon, coasted for a couple days, hit their entry interface, then hit the Pacific.

Why? Going back into orbit requires adding two more burns: one to enter Earth orbit, and another to leave it. Adding a rendezvous with the ISS (or any other floating payload) means an additional 1-2 burns to match the orbital planes, an additional burn to raise or lower your orbit, and God knows how long until the orbits of the two vehicles sync. Look at the space shuttle: even with matching the orbital planes and scheduling launch for an ideal rendezvous profile, it takes them 36-48 hours to catch up with the space station.

Trans-earth injection is complicated enough without adding all that. Extra burns means extra propellant, which means extra weight, which is exactly what you're trying to avoid. Not to mention, each of those steps is another opportunity for failure, and how do you abort if you don't have landing gear?

This is why they are Rocket Scientists(TM).

Re:Theyy could always ask Paul Revere ... (2, Informative)

Robonaut (1134343) | more than 6 years ago | (#21700418)

When returning from the moon, a spacecraft has significant excess velocity. Entering back into an Earth orbit (like rendezvousing with the ISS) means that the CEV would need to make a burn to slow down. This would consume a significant amount of fuel (that very well could weigh as much or more than the airbags). Instead, the Apollo CM and the CEV are designed to plunge directly into the Earth's upper atmosphere, literally burning off the excess velocity through atmospheric drag. This requires a larger heat shield, but lowers the mission complexity and fuel the spacecraft needs to carry.

Re:Theyy could always ask Paul Revere ... (1)

Brett Buck (811747) | more than 6 years ago | (#21700730)

Because that plan would involve FAR more weight than any proposed air-bag system. To "stop" at the ISS would require that a large amount of braking fuel be carried all the way to the Moon and back just to reduce the velocity to Earth Orbital velocity. As opposed to letting friction slow you down.

      There is some potential value in an Earth orbit "stop" on the way out (as was one of the baseline plans for Apollo, early on) but definitely not on the way back, if you can build a thermal protection system to take the full-speed reentry. Which we can, easily.

      Brett

Re:Theyy could always ask Paul Revere ... (1)

ZHaDoom (65485) | more than 6 years ago | (#21700732)

I do believe that the orbit of ISS was change in design to work with the more northern launch point of Russia. Making it a non idea orbit for a stepping stone to the moon or mars.

I understand NASA is on a short budget... (4, Funny)

explosivejared (1186049) | more than 6 years ago | (#21699808)

So... I don't really understand the whole disposable crew idea. It would make sense to reuse the crew rather than feeding them to sharks after re-entry, or did I miss something.

Re:I understand NASA is on a short budget... (1)

sm62704 (957197) | more than 6 years ago | (#21700252)

Hey, sharks gotta eat too, you insensitive clod. Especially the ones with lasers.

Re:I understand NASA is on a short budget... (1)

PrescriptionWarning (932687) | more than 6 years ago | (#21700366)

Just attach laser beams to the crew's heads so they'll have the advantage over sharks. Plus I hear shark is tasty :)

Re:I understand NASA is on a short budget... (0)

Anonymous Coward | more than 6 years ago | (#21700692)

Water landings plus aircraft carrier gives NASA time to swap out the robotic crew for the live actors.

Bad Summary? (2, Insightful)

2short (466733) | more than 6 years ago | (#21699854)


"landing on land was preferred in terms of total life cycle costs for the vehicles."

Landing on land is cheaper, check.

"eliminating the 1500 lb airbags for landing has its appeal"

Landing on land lets it be lighter, check.

"A splashdown in water seems to be favored."

Huh? WTF? Am I supposed to go RTFA or something?

Re:Bad Summary? (1)

mashade (912744) | more than 6 years ago | (#21699930)

I was puzzled in the same way. Perhaps it gets to be lighter if outfitted for nautical landing, and that simply wasn't made clear. [/didn't rtfa]

Re:Bad Summary? (0)

Anonymous Coward | more than 6 years ago | (#21699938)

Perhaps you are reading it wrong .. the landing bags are for LAND landing ..similar to the way the mars probes landed.

Re:Bad Summary? (1)

paulej72 (1177113) | more than 6 years ago | (#21699966)

The airbags are needed for landing on land not on water. This is where the problem lies.
The solution should be to have a no airbag model for moon missions and an airbag equipped model for IIS missions.

Lack of understanding. (2, Informative)

LWATCDR (28044) | more than 6 years ago | (#21700062)

"eliminating the 1500 lb airbags for landing has its appeal"

"Landing on land lets it be lighter, check."

The airbags are used for landing on LAND.
They are not flotation devices. Any thing that can fly is going to light enough float on water if it doesn't leak.
The airbags are to reduce the impact.

Re:Lack of understanding. (1)

p0tat03 (985078) | more than 6 years ago | (#21700652)

Except spacecraft rarely *fly*. They float in space, or they are free-falling back to Earth. Neither of which suggests any innate ability to stay afloat.

Re:Bad Summary? (1)

Criton (605617) | more than 6 years ago | (#21700440)

Getting rid of Ares I for Direct launcher would be even cheaper and solve the mass issues there would be so much extra payload with the direct 132 and 246 combo the Orion can go back to a 5.5M base diameter and have an orbital module. Another plus they can ax the J2S program and use a cluster of three RL60s on the EDS not only will this be cheaper the EDS can be 20 tons lighter. I strongly recommend against ever landing in the Atlantic that would be stupid at best direct launcher has no air start events the srbs are not ignited until the two RS68s are started and proven healthy just like the shuttle's three SSMEs.

Re:Bad Summary? (1)

PhxBlue (562201) | more than 6 years ago | (#21700464)

Huh? WTF? Am I supposed to go RTFA or something?

No, just read the summary a bit more closely. Landing on water lets the engineers ditch the airbags. Landing on solid ground without the airbag system would be a bit ... jarring, to say the least.

Re:Bad Summary? (1)

plague3106 (71849) | more than 6 years ago | (#21700486)

I think the airbags for for landing on land, not on water.

surface of earth is mostly water (2, Insightful)

192939495969798999 (58312) | more than 6 years ago | (#21699868)

It's much easier to hit the water, and in theory you should be able to get a softer landing on water. However, if you land in the middle of the south pacific, it's a bit more difficult logistically to pick you up from there and get you home, vs. landing on some runway with roads connecting it to the regular highway system of your homeland.

Re:surface of earth is mostly water (2, Informative)

GenKreton (884088) | more than 6 years ago | (#21699968)

They want to land on land for recovery reasons and to save the crew the effects of being stuck out in the ocean in a waving buoy. With that said, you hit the nail on the head, finding land and aiming at it is significantly harder. That's why both systems are in the engineering specifications NASA gave us, and will be built into the final design, tentatively. The system for placing the capsule at a good location is not one of the design challenges facing Lockheed Martin's contract.

Gotta give the carriers something to do... (1)

Chmcginn (201645) | more than 6 years ago | (#21700012)

When they're out in the middle of the Pacific doing exercises. Why not have them pick up some astronauts on their way?

Don't let them get away with half assing things (1)

Criton (605617) | more than 6 years ago | (#21700568)

We need to all write congress and get them to stop ares I and use direct launcher or and EELV. As for water landings these are historically very unsafe if you go by statistics spacecraft landing like an airplane like the shuttle,X15,and SS1 is the safest way to land with a soyuz type landing being the second safest manner in which to land. During the apollo program the crew was nearly killed twice by fuel reacting with sea water once during apollo 13 and another during the apollo soyuz test project. We need to stop the stick before it kills a crew and it will as one of the most dangerous things one can do in engineering is cut corners trying to make a too tight mass budget.

Probably both, it turns out (5, Interesting)

Thagg (9904) | more than 6 years ago | (#21699878)

Lockheed, the Orion prime contractor, has expressed significant reservations about carrying the heavy airbags to the moon and back -- those 1500 lbs can better be used in other ways. On the other hand, there shouldn't be a problem with the weight on the more common missions to the space station and low-earth orbit, and the ability to reuse the capsule will be far greater if they put it down on land.

The speculation in this week's Aviation Week was that they would have bolt-on airbags for the earth-orbit flights, and would recover those missions on the land, and would recover at sea for the moon-return missions.

The reentry profile for the moon missions is really quite amazing. Recently Aviation Week had an article about it, describing how to get all the capsules to recover to the same spot on Earth. Do you recall way back in the Apollo days, they always described the narrow re-entry corridor? Too steep and you'd burn up, to shallow and you'd skip back into space forever? Well...

For Orion, they plan to use a skip back into space to bleed off some of the speed coming back from the moon, and to align the craft to re-enter at the correct place to land where they want, off the coast of California. It's an incredibly audacious plan, with tolerances that have to be measured in tenths of a degree of entry angle. Very cool.

Thad

Re:Probably both, it turns out (1)

PieSquared (867490) | more than 6 years ago | (#21700462)

Exactly precise angles is one of the benefits of modern flight computers, which they didn't have for Apollo. I'd certainly expect them to put the crew in a pretty small circle in the ocean if they wanted to, today. Hell, I wouldn't be *that* surprised if they could land them in a big lake... or better yet a harbor or bay. the space shuttle manages to hit a runway, after all. Sure, it has wings and whatnot, but this is 20 years later, and a lake, bay, or harbor could be quite a bit larger.

What is the downside? (2, Insightful)

BlueParrot (965239) | more than 6 years ago | (#21699952)

To be honest in principle I don't see the downside of a water landing. The craft has to have a sufficiently low density to float, which could increase air resistance, but a certain degree of air resistance will be needed for re-entry anyway, too little of it and the majority of the slowdown will occur in lower ( i.e denser ) parts of the atmosphere. You want to decelerate over as long a distance as possible tor educe the requirements on the heat-shield. I guess you must test the whole thing for water-compatibility, but if it is to deal with vacuum, intense heat, and solar wind, I would imagine it should be able to deal with some water. I suppose there may be investment costs associated with developing new technology for water based landings, but it does seem like it should be the easier and more fault-proof way to do it, so I wouldn't be surprised if it will work out cheaper in the end.

Re:What is the downside? (1)

kilo_foxtrot84 (1016017) | more than 6 years ago | (#21700052)

You raise valid points... but you also have to fund the fuel and other logistics for the ship that has to go pick the capsule up. If the capsule might land off target, then maybe you should have a backup ship or two... financially, it adds up quickly.

Re:What is the downside? (1)

T.E.D. (34228) | more than 6 years ago | (#21700262)

To be honest in principle I don't see the downside of a water landing.

For one thing, we all know a seat cushion will make a terrible flotation device.

Re:What is the downside? (2, Informative)

CompMD (522020) | more than 6 years ago | (#21700272)

Its not the water that is a problem, its the salt in that water. You run into accelerated corrosion problems with exposure to ocean water.

Re:What is the downside? (0)

Anonymous Coward | more than 6 years ago | (#21700278)

Just because a vehicle is air tight for space does not mean it is good for water.

I do not think there is crushing 'Space pressure' exerted on the vehicle, instead there is a pulling pressure from the vaccume. (Actually the air trying to get to the vaccume.) In contrast, as you go deeper into water, there is significant pressure from the force of the water.

Re:What is the downside? (0)

Anonymous Coward | more than 6 years ago | (#21700414)

Salt water

One vote in favor of landing on land (2, Insightful)

timeOday (582209) | more than 6 years ago | (#21700016)

Gus Grissom [wordpress.com] :

"Following the splashdown of "Liberty Bell 7, the hatch, which had explosive bolts, blew off prematurely, letting water into the capsule and into Grissom's suit. Grissom nearly drowned but was rescued by helicopter, while the spacecraft sank in deep water. Grissom maintained he did nothing to set off the explosives to blow the hatch, and NASA officials agreed. The craft was recovered in 1999 but there was no evidence of how the hatch had been opened. However, later experience showed that the force necessary to trigger the initiator for the explosive egress system would leave a major bruise, and Grissom had no such injury."
Actually I'm not sure this episode has any direct relevance to the present. Just thought it worth mentioning that the first manned space missions did land in water.

Re:One vote in favor of landing on land (3, Insightful)

Hemlock Stones (636570) | more than 6 years ago | (#21700084)

No, the first manned missions landed on land. The Soviet Union (now Russia) landed and continues to land all of their manned missions on land. If they can do it surely we can too.

Re:One vote in favor of landing on land (1)

Black-Man (198831) | more than 6 years ago | (#21700386)

It was quite an issue at the time. They accused him of blowing the hatch. Maybe they don't want to go down that road ever again.

What I don't get (3, Interesting)

BorgDrone (64343) | more than 6 years ago | (#21700046)

What I don't get is the continued use of rockets. Is going straight up (the brute force & ignorance method) really the most efficient method of getting up there ? Isn't an approach like SpaceShipOne uses more efficient in terms of amount of energy needed per kilo of launched mass and thus costs ?

SpaceshipOne * 30 (4, Informative)

Harmonious Botch (921977) | more than 6 years ago | (#21700398)

Spaceship one was good for getting to the 'edge of space' and back. Being in orbit is a different thing. As a general rule, it takes 30 times as much energy to get into orbit as it does to just get up there. ( the number varies with altitude, of course, but 30 is a good back-of-the-envelope approximation ). The energy that has to be bled off when coming down is roughly 30-fold. So spaceshipOne is not even close to being able to do it. It requires new materials and/or a new design. Or stick with the high maintainence and unpleasant failure rate of the shuttle.

Or you can stick to the simple way of doing it with rockets and parachutes.

Re:What I don't get (2, Insightful)

Nyeerrmm (940927) | more than 6 years ago | (#21700628)

If you're talking about air launch, it only gives you a minor improvement, and if you're talking about a heavy launch vehicle like Ares V, you're not going to find an aircraft capable of launching it. The Orbital Sciences Pegasus rocket launches off of an L-1011 aircraft, and has a fairly small payload.

Remember that most of your energy is spent with energy in the direction of the orbit rather than going straight up, and thus why orbital flight is an order of magnitude more difficult that the suborbital flight that SpaceShipOne did.

Re:What I don't get (2, Insightful)

Robonaut (1134343) | more than 6 years ago | (#21700746)

In theory, yes you are right. A couple things to remember however:

1)SpaceShipOne was sub orbital (did not reach orbital velocities) and launching into orbit would require a couple orders of magnitude more energy/fuel.

2) Everything else being equal, a spaceplane will cost more to develop than a rocket (aluminum tubes vs a plane airframe capable of hypersonic flight). Development costs are rather significant for spacecraft as the number of units produced is very low.

3) It has been tried before, rather unsuccessfully: http://en.wikipedia.org/wiki/Rockwell_X-30 [wikipedia.org]

Well theres one thing I can say.... (1)

edwardpickman (965122) | more than 6 years ago | (#21700076)

Itll make a big splash.......sorry...very very tired.

Moot point, Orion will never fly (-1, Flamebait)

gelfling (6534) | more than 6 years ago | (#21700150)

After the Space Shuttle, manned spaceflight in the US will be officially over.

Re:Moot point, Orion will never fly (1)

TrippTDF (513419) | more than 6 years ago | (#21700500)

Don't be so sure... A lot of other countries are eyeing the moon and beyond now, and the US isn't going to let the final frontier go. It would be a gigantic tactical mistake. Even if Orion doesn't do a lot, it's important to keep our foot in the door in case China makes some serious headway with their own program, which seems likely to me.

Missing option (0)

Anonymous Coward | more than 6 years ago | (#21700156)

Giant Ass pool of Gelatin. Its not has hard as ground, not as liquid as water, can give to hungry ppl after landing. If NASA wastes 10% of the cash in parties/lunch/dinners after a job well done why not this?

no! (2, Insightful)

Scrameustache (459504) | more than 6 years ago | (#21700254)

I'm 111% confident that it cannot land in water.

Because it's water, not land, DUH!

Skip water recovery weight (4, Informative)

Chairboy (88841) | more than 6 years ago | (#21700274)

For the folks saying "use the ISS!': Won't work. When coming back from the moon, the approach speed is far too high to enter the orbit that the ISS or any other reasonable future space station is in. The braking is done through friction as the spacecraft enters the earth's atmosphere, and provides MUCH more delta-v than would be feasible by using rockets.

To use the ISS, the spacecraft would need to perform a complex aerobraking maneuver (basically, a partial re-entry), then have the fuel needed to circularize its new orbit so that it can rendesvous with the ISS. By the time this is done, the design for the capsule is far heavier than the 1,500lb penalty that airbags impose.

My idea, make the water landing a known 'capsule loss' scenario, the same way it is with the Shuttle. If things go _so wrong_ that a water landing is unavoidable (say, launch failure) then design the capsule for quick-egress after a water landing. Airplanes ditch in water and people have time to get out before they sink. My Piper Cherokee will float long enough for me to climb out onto the wing, and for a real shock look at the survival training that helicopter passengers go through in the military, that's some pretty intense worst case scenario stuff.

With Rogallo steerable parachutes, landfall should be available at all times except the first few minutes of launch. Skip the airbags, make the capsule so it stays afloat just long enough for egress, and train the astronauts on how to get out fast.

Bring back the Saturn V! (1)

mcsqueak (1043736) | more than 6 years ago | (#21700280)

I really like the idea of sending people and cargo into space on rockets... I guess it just strikes some sort of nostalgic cord with me, reminding me of the optimism that went into the cold war space race, Kennedy's famous speech, and all of that. My favorite rocket design was the Saturn V, designed by Von Braun. It had the highest payload capacity of any spacecraft, and it was the launch vehicle for many important Apollo missions. I hope they look back to the Saturn V for design clues while making this new vehicle.

The Mercury capsules landed in the ocean (0)

Anonymous Coward | more than 6 years ago | (#21700396)

Following the splashdown of "Liberty Bell 7", the hatch, which had explosive bolts, blew off prematurely, letting water into the capsule and into Grissom's suit. Grissom nearly drowned but was rescued by helicopter, while the spacecraft sank in deep water.

http://en.wikipedia.org/wiki/Gus_Grissom [wikipedia.org]

So, we've landed in the ocean before and found at least one problem with the approach.

Perhaps... (1)

FireIron (838223) | more than 6 years ago | (#21700456)

Maybe they're hoping to find a genie!

Design it to do both (1)

gatkinso (15975) | more than 6 years ago | (#21700632)

don't see why this approach (other than $) is not taken.

If weight reduction is the issue.... (0, Offtopic)

Fallen Kell (165468) | more than 6 years ago | (#21700776)

How in the WORLD can it be lighter for the vehicle to land on "terra firma" then in the water? Landing gear, tires, hydrolics, electric motors, brakes, etc., etc., all weight a LOT. Certainly more then 1500 lbs that they are stating for the air bags for a water landing.
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