Okay, I know that the CEV is a replacement for the shuttle and it has a lot of advantages. It (should) be cheaper. It's simpler and hopefully safer. It has the ability to be used for lunar missions and adapted for other sorts of missions.

However I cannot help but feel disipointed in the capabilities lost. The Shuttle is very expensive and has a rather bad safety record. However it can do things that the CEV never will be able to. It can not only carry payloads to orbit but also retrieve them. It can conduct external in-orbit experiments such as deploying retrievable satellites and has been used for things like solar panel experiments and the teather satellite (which admittedly didnt go as well as hoped).

Biggest thing of all though is the ability to service satellites in orbit. A level of orbital servicing capability no other vehicle has come close to. Additionally it has much greater capacity. For Space Station missions it can bring up external components and replacement parts. The only alternative would be to use a dedicated launch for things like medium-sized external replacement parts. It can even carry ISS modules, making it an important player in the maintiance of the space station.

The CEV system used a lot of shuttle technology. The solid rocket booster is essentially the same, at least the majority of the sections. The liquid tanks are based on the shuttle's external fuel tank. It uses the same launch pads.


Would it be possible and worthwhile it switch to the CEV for the majority of space exploration but to keep one shuttle in fight-worthy status and the others in semi-mothballs? The remaining shuttle might fly, say, once or twice a year, mostly for space station support and also remain if needed for some other mission.


I have heard that nasa plans to shut down a lot of the shuttle support facilities, however does it really cost that much to keep the capability if much is shared with the CEV? What is the price of keeping a hanger tooled for servicing the shuttle if one considers that it won't actually be used for the work nearly as often as in the past and will often just sit idle for most of the year?

I suppose I could see how the fuel tank fabrication capability might cost something. It's not that much different than the Ares fuel tanks. I suppose NASA could have several fuel tanks fabricated to keep as a supply for a few years of possible missions without having to retool to manufacture more.

Nice in theory, but maintaining ground facilities for two systems isn't practical.

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I'm not completely heartless, the doctor who removed it told me he'd never be able to get it all.

If money were no factor, then sure, you could keep a Shuttle and the CEV. Unfortunately, money is always a factor. The Shuttle requires a large ground support staff of trained personnel. You need people to prepare all of the Shuttle systems, update the software, and perform mission control.

A Shuttle also requires a lot of dedicated equipment and facilities. Some of those facilities will be converted for CEV operations (just like how the Saturn V launch pads were converted for Shuttle operations), so you'd either have to build duplicate facilities or somehow modify them to serve both vehicles. All of this costs money that NASA doesn't have, so it isn't going to happen.

As for the Shuttle's unique capabilities, the ability to return stuff from space is probably the most overrated. It is almost never cost effective to fly a Shuttle mission to retrieve something from space. It was done for the LDEF because the mission was specifically designed that way. They retrieved a small number of satellites (2 or 3 IIRC) that were left in useless orbits and brought them back so they could be launched again. However, the taxpayers heavily subsidized those recoveries.

While the cheap robotic servicing capability has been slow to show success, it is something that is under development, and has much greater likelihood to be less expensive than launching a whole new replacement satellite *and* won't be restricted to fixing low Earth orbit things.

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Forming opinions as we speak

Many airports have ground facilities for a dozen aircraft types, so NASA should be able to handle two or three. Obviously NASA should make sure the new system is really better before they retire the shuttles. The shuttle needs to fly more than once per year, or sufficient ground personel with experience won't be available just before flight time. Is there any chance a shuttle could be stationed at the ISS to use for emergencies? With the solid state boosters leaving from ISS, the shuttle could likely land at a moon base in hours instead of days. Neil

So; If NASA can launch a few hundred flights every day, then I would have no problem giving them multi-platform capabilities.
(Anyway, don't they already support Delta and other unmanned launchers as seperate vehicles?)

My garage at home can also support two vehicles. Do I have use for 2? No.

Sorry to be snippy, but the scales are so vastly different that there is no comparison.

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Numbers are not case sensitive. (me)

Two questions:

1. Do you necessarily need two entirely sets of separate facilities for two systems which share a large number of components?

2. How much does it cost to "maintain" all the shuttle facilities, assuming that they are not in operation to the extent that they were at the time of the shuttle program's most activity.

Does it cost anything to have a runway for the shuttle? It's already there. It's very thick concrete so it ain't going anywhere.

Does it cost that much to have the equipment for tile inspection and repair retained? What is the price of having some shuttle-speffic maintenance equipment sit in the back of the hanger under a tarp for most of the year?

I assume Nasa isn't so pressed for space that they simply to not have the room to keep such things and have no alternative but to throw them out or sell them for next to nothing at a government auction.

Obviously there are some shuttle-speffic facilities which would require money to keep in operation. But really, does it cost *that* much to have them for one or two missions a year?

The employees who are already trained in prepping the shuttle cannot also handle the CEV?

Refurbishing the shuttle after a flight requires a lot of highly skilled, highly specialized labor. One of the hope of the CEV is that this kind of maintenance will no longer be needed, and the staff to support it should be *much* smaller.

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Forming opinions as we speak

The Shuttle has a limited on-orbit lifetime. Stretching the consumables to the utmost, you're not going to get more than a month of life out of it. After that, the Shuttle dies.

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"Time travel gives me a headache." - Capt. Kathryn Janeway

Many airports have ground facilities for a dozen aircraft types, so NASA should be able to handle two or three

Weak comparison. Aircraft don't need dedicated runways - just about any plane that meets the weight and size constraints can take off from any runway. The same isn't true for launch pads. Aircraft have standardized many factors like fuel types and fueling system, baggage handling, etc. None of that is true for rockets.

Is there any chance a shuttle could be stationed at the ISS to use for emergencies?

This was discussed in a recent thread. In short, the answer is no. The Shuttle wasn't designed to be left on orbit for extended periods of time. Many of the systems (e.g. the fuel cells) aren't designed to be used for more than a couple weeks.

With the solid state boosters leaving from ISS, the shuttle could likely land at a moon base in hours instead of days.

The idea of using a Shuttle SRB in orbit to speed up a Mars trip was discussed just a week or so ago. The first problem is that a single 4 segment SRB weighs something like 1.2 million pounds. There's no booster on Earth powerful enough to launch even a single SRB segment into orbit much less an entire SRB.

1. Do you necessarily need two entirely sets of separate facilities for two systems which share a large number of components?

There can be some commonality but probably not much. For example, look at the geometry of the Shuttle verses the Ares I (the "Stick"). The launch pad will probably have to be modified. The crawler will probably need specialized equipment to move the Ares to the launch pad. The launch tower will be different. The list goes on. The equipment to stack a 5 segment SRB for the Ares I will likely be similar to that used to stack a 4 segment SRB for the Shuttle. The upper stage engine on the Ares I burns the same propellant (LH/LOX) as the SSMEs but the engine is completely different. The software won't be the same. The processing procedures won't be the same. The amount of commonality is actually pretty limited.

There appears to be more commonality between the Ares V and the Shuttle. The geometry is similar so the pad, crawler, and perhaps the launch towers wouldn't require too many changes.

2. How much does it cost to "maintain" all the shuttle facilities, assuming that they are not in operation to the extent that they were at the time of the shuttle program's most activity.

If I'm reading you correctly, it seems you're asking how much it would take to put the Shuttle facilities in either a caretaker status or to operate them at a lower activity level. I don't have the answers. Every building requires a certain amount of maintenance. Physical equipment needs to be maintained whether its used or not if you hope to use it again in the future. The big issue is that most of the facilities will be converted for use by the new vehicle(s) so they won't be available for the Shuttle anymore. There's also the other support equipment such as the simulators and training aircraft that exist to train Shuttle astronauts. The simulators for the CEV will either be adapted from Shuttle hardware (seems unlikely) or will replace the Shuttle equipment. The training aircraft won't be needed anymore. It takes a lot of expensive equipment to keep the Shuttle pilots proficient. That's true whether they're flying 1 mission a year or 6.

Does it cost anything to have a runway for the shuttle? It's already there. It's very thick concrete so it ain't going anywhere.

It isn't like they're going to rip out the runway when the Shuttle stops flying. However, it's likely that the runway deteriorates due to exposure to the elements whether it's used or not. I've seen photos of abandoned runways at closed airports. After a few years, many of them appear to be in pretty bad shape.

Does it cost that much to have the equipment for tile inspection and repair retained? What is the price of having some shuttle-speffic maintenance equipment sit in the back of the hanger under a tarp for most of the year?

I assume Nasa isn't so pressed for space that they simply to not have the room to keep such things and have no alternative but to throw them out or sell them for next to nothing at a government auction.

It isn't as if NASA has a bunch of empty buildings sitting around where they can store stuff. Most of their buildings are already being used for one purpose or another. How much sense would it make to build a building to store equipment that you're not likely to use again?

Obviously there are some shuttle-speffic facilities which would require money to keep in operation. But really, does it cost *that* much to have them for one or two missions a year?

The employees who are already trained in prepping the shuttle cannot also handle the CEV?

It does cost a lot if you have to build new buildings to have enough room to handle all of the support equipment and personnel needed to maintain both vehicles. As for the employees, consider the people who refurbish the SSMEs and the Shuttle's tiles. Those components are highly specialized and won't exist on the CEV. You have to pay the workers the same salary regardless of whether you're flying 1 (or zero, as when the Shuttle was grounded) or 6 missions a year. Keeping that workforce on hand to support that few missions per year is an expensive proposition. The same goes for the mission controllers. The vehicles are so different that it'd be challenging to train the mission controllers to handle both types. Would you keep a full complement of mission controllers on staff when you're only flying 1 mission per year?

The solid rocket boosters used by the Shuttle are high thrust, which is great for getting the Shuttle and its external fuel tank off the ground, but have very poor efficiency in general, and in a vaccuum in particular. They're also incredibly massive, massing roughly 590,000 kg each. By way of comparison, the ISS currently masses 232,693 kg currently. How many flights did it take to put those ISS components in orbit?

NASA actually produced a 10-page study on using the Shuttle for missions to the Moon. Their plan called for a Shuttle carrying its EFT all the way into orbit with it, and then leaving it there, while cargo flights then carry up the liquid hydrogen and liquid oxygen needed to refuel it - that's 106,261 kg of liquid hydrogen, and 629,340 kg of liquid oxygen. With no "Shuttle-C" cargo vehicle, the Shuttle itself could deliver 24,400 kg of cargo each flight, while a Delta IV Heavy can deliver 23,040 kg. So, we're talking roughly 30-31 flights between the two to fill it.

It gets better - they estimated a 3-ton payload to the Moon. That's not much.

URL for the study can be found here:

http://ntrs.nasa.gov/archive/nasa/ca...1991014907.pdf

PDF is 1,141 KB.

Noteworthy quote:

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Sleep? Isn't that that totally inadaquate substitute for caffeine I've heard so much about?

Quantumfoamy.com, my astronomy/astrophotography blog.

Actually, on a somewhat related note (The deployment of the CEV) can we get that thing possibly flying in the more near-term by going with the capsule and for the time being sticking it ontop of an atlas or even a delta or something?

Maybe even get some CEV orbital missions before the shuttle retirement deadline is up.

(oh yeah... not human certified... is it that much easier\faster to make a whole new launch platform than to assure an existing one is adequately safe)

Whatever happened to those cool digital vehicles you used to see in magazines that would be just like airplanes, instead of needing the extra tanks like the Shuttle?
Man, I felt so old writing that.

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"If you think the LHC will create black holes, you might as well believe Hobbits are at the bottom of your garden."- Dr. Mike Inglis
Rovers forever! - ToSeek
"Carl Sagan sent a message to ET,
Neil Armstrong walked in the Sea of Tranquility
Steve Squyers built Spirit and Opportunity
Dan Haylen upchucked in zero gravity." -Brent Simon, The Space Camp Song

How do you think I feel? I've been seeing those same "any day now" spaceplane illustrations since before they were digital!

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

Ah, we both remember those days- four Harry Potter books, 150 Pokemon, President Clinton, the first plans for ISS... why did I have to grow up?

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"If you think the LHC will create black holes, you might as well believe Hobbits are at the bottom of your garden."- Dr. Mike Inglis
Rovers forever! - ToSeek
"Carl Sagan sent a message to ET,
Neil Armstrong walked in the Sea of Tranquility
Steve Squyers built Spirit and Opportunity
Dan Haylen upchucked in zero gravity." -Brent Simon, The Space Camp Song

Try 1970's. The basic concepts aren't new, just repainted and with the serial numbers filed off.

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"If this were play'd upon a stage now, I could condemn it as an improbable fiction."
Shakespeare, Twelfth Night
Illuminati's Razor-The most complicatedly evil answer is usually the most correct answer. - Fazor
"Every book is a children's book if the kid can read." - Mitch Hedberg
"Distance doesn’t matter much in space, where if you just start a thing off with the right kind of shove, sooner or later it will get where you want it to go." -Frederik Pohl, Mining the Oort

I was joking before.
But I'm all for Orion, let's go, go, go!

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"If you think the LHC will create black holes, you might as well believe Hobbits are at the bottom of your garden."- Dr. Mike Inglis
Rovers forever! - ToSeek
"Carl Sagan sent a message to ET,
Neil Armstrong walked in the Sea of Tranquility
Steve Squyers built Spirit and Opportunity
Dan Haylen upchucked in zero gravity." -Brent Simon, The Space Camp Song