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Laguna
2008-Oct-30, 10:06 AM
How long before space rockets become as cheap as cars? Technically a car is more complex than a rocket so whats the game? Why is it so expensive? Is the government scared of letting people into space or something?

It ain't rocket science. Its just engineering.

I want my space rocket!
:)
You are kidding, right?

Laguna
2008-Oct-30, 10:27 AM
The first cars were monstrously expensive too. Probably.

If they assembly lined rockets then they would be just as cheap. Its just a big missile. You don't even need to buy a warhead for it.

Metal, fuel and overpaid engineers. Thats all you really need isn't it. Whats so hard?
Have you ever compared the size alone of a rocket in relation that of a car?

Laguna
2008-Oct-30, 10:33 AM
Let us compare a rocket (Lets take ESAs Ariane 5) to a car.
One one side we have a car.
Mass about 1.2 tons
contains about 0.05 tons of fuel to burn in about 6 hours.

One the other side we have the rocket.
Mass of 750 tons.
contains about 200 tons solid propellant to burn in 130 seconds
and 150 tons of liquid propellant to burn in 10 minutes.

And now tell me again that a car is less complex to engineeer as a rocket...

Man, I do work in the automotive industry, yes cars are getting more and more complex, but I would never compare them to a rocket...

geonuc
2008-Oct-30, 10:40 AM
I believe our Aussie friend said cars are technically more complex, not more complex to engineer - a subtle difference.

But I think it's a good question. Cars certainly comprise vastly more moving parts that must interact harmoniously, not mention the engineering that goes into comfort, reliability, repairability, style, etc. Mass production can't account for all of the difference in cost. It's a good question.

Laguna
2008-Oct-30, 10:44 AM
I believe our Aussie friend said cars are technically more complex, not more complex to engineer - a subtle difference.

But I think it's a good question. Cars certainly comprise vastly more moving parts that must interact harmoniously, not mention the engineering that goes into comfort, reliability, repairability, style, etc. Mass production can't account for all of the difference in cost. It's a good question.
Still, try to build an engine thats puts through 200 tons of propellant in 130 seconds without going boom... Sure it has less moving parts, but still...
It takes a lot of high qualified engineers to do that and you only get a handful of ready products out of it.
On the other hand, how many rockets are build per year? How many cars?
Would you expect to sell as many Ariane 5 rockets as cars if they would be comparable in price? Would you like to pay the gas bill? :lol:

Laguna
2008-Oct-30, 11:01 AM
Well there are "civilians" struggeling while trying to get their tanks with a nozzle into space too.
Ask them why they do not sell their rockets for cheap to anybody at Wal Mart.

geonuc
2008-Oct-30, 11:07 AM
It takes a lot of high qualified engineers to do that and you only get a handful of ready products out of it.
On the other hand, how many rockets are build per year? How many cars?
This is the mass production component to the question, which has been acknowledged.


Would you like to pay the gas bill? :lol:
Huh? I don't think anyone is suggesting that rockets should get great fuel mileage.

Laguna
2008-Oct-30, 11:14 AM
The V2 could have reached space. Thats 1940's technology.
Possibly, but they never tried.


Probably because America bombs those countries into the stone age every time they try. Maybe they should stop calling them longrange missiles.
They do? I never saw them bombing Hawthorne (Los Angeles) California...
[/quote]


I'll bet the private industry could do it. Just take it out of the hands of governments and I reckon there will be a Hilton on Mars within a decade.
They already do, thats what I am talking about. Go, ask Space X whey they do not sell you a rocket to get into space. They are developing one since 2002. Since then my company had produces two new generations of cars. So it should be plenty of time to develop a rocket...

Laguna
2008-Oct-30, 11:22 AM
As far as I know SpaceX has sold all payload on the next upcoming flights. So it can't be that bad... They still do exist and continue.
What other companies did NASA drive out of the race?

LotusExcelle
2008-Oct-30, 11:24 AM
Shouldn't this be in CT instead of OTB?

Either way: Rockets are *NOT* just tanks with nozzles. They are *complicated*. Fiendishly complicated or you would have one in your backyard right now. They take exacting engineering, exacting materials, and flawless assembly or else they go *boom* rather suddenly.

geonuc
2008-Oct-30, 11:48 AM
Shouldn't this be in CT instead of OTB?

Either way: Rockets are *NOT* just tanks with nozzles. They are *complicated*. Fiendishly complicated or you would have one in your backyard right now. They take exacting engineering, exacting materials, and flawless assembly or else they go *boom* rather suddenly.
Well, if this turns into a NASA CT thread, then I'm outta here.

But, that aside, the OP still has me curious. Sure, rockets require exacting technology, materials and assembly. But we already know how to do all that. The R&D has been done (by NASA and others). So why can't someone with, say $10M, build a decent rocket?

There must be a reason, or SpaceX would have many successful launches by now. But I haven't heard that reason yet.

Laguna
2008-Oct-30, 11:54 AM
Well, if this turns into a NASA CT thread, then I'm outta here.

But, that aside, the OP still has me curious. Sure, rockets require exacting technology, materials and assembly. But we already know how to do all that. The R&D has been done (by NASA and others). So why can't someone with, say $10M, build a decent rocket?

There must be a reason, or SpaceX would have many successful launches by now. But I haven't heard that reason yet.
The reason is that it is not that simple to burn 200 tons of propellant in under two minutes in a controlled way without blowing the hole thing up.
You have do direct the HUGE exhaust exactly. You have to construct an engine that can withstand the massive pressure and heat. You have to steer your engine very precicely. You have to make this massive burn stable and without any hickups. You have to manage stage separation without loosing track. You have to make your rocket do this on its own. No steering wheel, no shift sick, no brakes, only one way. Either up or boom.

If your car has a problem, you get it to a garage. If your rocket has a problem, you are dead!

LotusExcelle
2008-Oct-30, 12:02 PM
That's exactly why i don't want to transfer to working on airplanes. Something goes wrong with a car you pull over and have it towed. That happens with a plane... well... yeah. Same with rockets.

geonuc
2008-Oct-30, 12:09 PM
The reason is that it is not that simple to burn 200 tons of propellant in under two minutes in a controlled way without blowing the hole thing up.
You have do direct the HUGE exhaust exactly. You have to construct an engine that can withstand the massive pressure and heat. You have to steer your engine very precicely. You have to make this massive burn stable and without any hickups. You have to manage stage separation without loosing track. You have to make your rocket do this on its own. No steering wheel, no shift sick, no brakes, only one way. Either up or boom.
Don't we already know how to do all that?

Laguna
2008-Oct-30, 12:09 PM
That's exactly why i don't want to transfer to working on airplanes. Something goes wrong with a car you pull over and have it towed. That happens with a plane... well... yeah. Same with rockets.
Even worse with rockets!
Planes can glide, even without engines. They are even build to land.
Rockets can neither land nor glide. They usually go *booom* if something goes wrong.
How many people have you seen coming out of a failed rocket launch alive?

Laguna
2008-Oct-30, 12:13 PM
Don't we already know how to do all that?
Well, I do not.
NASA knows, ESA knows. The Chinese know. The Indians know. The Russians know. SpaceX just found out how to do it.
But this does not mean it is as easy as riding a bike. It still is extremely difficult and making even a little mistake, one you would not even notice when sitting in your car, would end your launch on the pad.

antoniseb
2008-Oct-30, 01:09 PM
A sock Puppet has been removed. Some of his/her quotes remain in other poeple's posts.

samkent
2008-Oct-30, 01:14 PM
The OP is correct in his thoughts that if we mass produced rockets the price would drop by a substantial amount. But he is overlooking one very important factor.

We don’t need very many rockets per year.

Even if we use the figure of $2000 per pound into orbit, That’s $300,000 per person. And that doesn’t factor in the cost to get that same person back on the ground. How many pounds of hardware would the de-orbit add to the bill? I would expect it would be several times the weight of the human cargo. So right there you are well over a mil per person. I don’t know about your accounts but mine have dropped quite a bit the past couple of months. So even if it was just $1 million I would still have to save for a couple hundred years for my one day in orbit.

You can prove to yourself just how easy it is. Just build a small rocket to launch a mouse to one mile altitude. Then build one to launch that experienced pilot mouse a horizontal distance greater than 25,000 miles.

It’s easy!

geonuc
2008-Oct-30, 02:05 PM
Well, I do not.
NASA knows, ESA knows. The Chinese know. The Indians know. The Russians know. SpaceX just found out how to do it.
But this does not mean it is as easy as riding a bike. It still is extremely difficult and making even a little mistake, one you would not even notice when sitting in your car, would end your launch on the pad.
Easy as riding a bike? Whoever claimed that?

By 'we", I obviously didn't mean you and I.

You seem to keep coming back to the idea that if you make a rocket mistake, it goes boom, unlike with, say, a car. But keeping your vehicle from going boom is not the total definition of success. I submit that engineering and producing a passenger vehicle that meets the standards demanded by today's consumers, with all the safety and comforts implied there and that will last at least 100,000 miles in all weather conditions, over all types of roads and with little to no maintenance, represents a greater achievement than putting a rocket in space.

But that's not even the point I'm trying to make (or ask). We know how to build that car (the Japanese do, anyway) and we know how to build that rocket.

The question is, why does SpaceX have to spend gobs of money developing something that has been essentially developed already? Why can't they just call up General Dynamics, Northrup, Boeing or whoever the contractor is, and say "You know those Atlas rockets you build for NASA? We'd like ten of them. How much?"

LotusExcelle
2008-Oct-30, 02:13 PM
Some knowledge IS proprietary, for one. Some may even be classified. Plus things in rockets don't really scale very well, if I understand them correctly.

Laguna
2008-Oct-30, 02:26 PM
Some knowledge IS proprietary, for one. Some may even be classified. Plus things in rockets don't really scale very well, if I understand them correctly.
I think his point is, why can't they simply go to BOEING and simply order one like I can go to GM and simply buy a car...

LotusExcelle
2008-Oct-30, 02:35 PM
Ah. Rockets flying around willy-nilly may lead to, at the very least, house fires. And so on.

NEOWatcher
2008-Oct-30, 02:41 PM
I think his point is, why can't they simply go to BOEING and simply order one like I can go to GM and simply buy a car...
What are you going to use as a trade-in? :lol:

I guess it's just an upgrade from model rocketry.

Then there's that issue about colors, floor mats, and a leather wrapped abort handle.

In reality though, if you hold with the analogy, you still have governmental stumbling blocks buying a car. Tax, title and licensing. That can be murder with a rocket.

Laguna
2008-Oct-30, 03:18 PM
What are you going to use as a trade-in? :lol:

I guess it's just an upgrade from model rocketry.

Then there's that issue about colors, floor mats, and a leather wrapped abort handle.

In reality though, if you hold with the analogy, you still have governmental stumbling blocks buying a car. Tax, title and licensing. That can be murder with a rocket.
All you need is a driving licence for a space rocket... :lol:

geonuc
2008-Oct-30, 04:37 PM
You guys are funny. But, yeah, that's what I mean. To make a better analogy, if I had a new nuclear power plant and needed a turbine generator set, I certainly wouldn't contract someone to figure out how to convert steam enthalpy to electrons. I'd call up General Electric and order one.

ngc3314
2008-Oct-30, 05:24 PM
I think one of SpaceX's (et al.) founding principles is the notion that the Usual Suspects (Boeing, LockMart, whatever's left after mergers) have practically no incentive to drop the price of launch vehicles, and they have most of the (written and unwritten) expertise. They do OK selling launches to government agencies and for comsats, and wouldn't be too happy at selling launches much cheaper than they do already. Hence an upstart wants to come along, work everything out from scratch taking full advantage of knowledge now in the public domain, and own all the necessary expertise to see how cheaply it can really be done. Even NASA has found that unwritten things are important - much of the engineering to deal with thrust instability issues in the Saturn V's F-1 engines happened so late in the development that it was not completely documented - one of the reasons that teams went running around a few years ago to capture whatever oral information they could for relevance to the Ares V.

Of course, as Henry Spencer has been stressing for a couple of decades, the fact that rockets aren't reusable makes R&D a whole different game than for aircraft, much less cars. Compounding that, economics continue to make reusable rockets and spaceplanes more of a seductive dream than an advantage. To quote Spencer, shuttles aren;t so mch reusable as they are salvageable. (This made more sense in the NASA of the 1970s which had a huge work force left over from Apollo even after contractor layoffs, and was able to contemplate what now seems an incredibly labor-intensive system).

NEOWatcher
2008-Oct-30, 05:40 PM
All you need is a driving licence for a space rocket... :lol:
The written exam is done in Houston, and the road test is done on a simulator. But, you can also go for an international license if you're willing to take a trip out of the country.

Laguna
2008-Oct-30, 06:25 PM
You guys are funny. But, yeah, that's what I mean. To make a better analogy, if I had a new nuclear power plant and needed a turbine generator set, I certainly wouldn't contract someone to figure out how to convert steam enthalpy to electrons. I'd call up General Electric and order one.
But you would get into difficulties buying a whole new nuclear plant.
Some things simply are not for sale because they contain the companies key technologies.
And when you have the monopol in the market it is your interest to dictate the price.

Thats how our economics work.