Space X to build reusable launch vehicle

[GIThruster]

About the sensors and looking down: I could imagine a simple short arm swinging out a camera/sensors from the side of the vehicle

That was my thought as well. I'm not saying it can't be done. I'm just unconvinced what needs to happen in order to land in such a way justifies the added risk and engineering. In the case of Falcon (which was the issue after all) there's huge risk to land it under power. That first stage is mighty tall, and the center of mass is so far above the center of lift, that it's going to tip quite easily.

What's to be gained from powered landing? Obviously, you don't have to retrieve at sea nor ship back to the plant. Put the reprocessing plant by the retrieval site (which they didn't do) and you can save the cost of shipping.

It comes down to a cost/benefit analysis with risk weighed in. You're tempting me to think it's a useful option, and it certainly is cool--has always been--but I just can't see adding the risk without huge savings.

In any case, we're agreed, SpaceX rules. They're going to show literally EVERYONE the right way to do space launch.

[GIThruster]

Is there a real difference in the delta V that means a horizontal TOL and vertical TOL vehicle can't be the same weight?

The problem comes down to practical issues that are not immediately obvious. Lots of people like the horizontal take off option--it reminds immediately of commercial air travel. The Indians are still chasing this with the AVATAR project. Bussard had this in mind for a poly powered launcher, as did USAF with their study of fusion thrusters.

Trouble turn out to be: a) you need heavy landing gear because you're running all that fuel along a runway at high speed during takeoff and b) you end up melting your infrastructure. It's pretty spendy to make a runway that can take that sort of abuse.

These are why people have been playing with combined cycle for decades, especially including liquifying air so you don't have O2 onboard at takeoff. That's a very complex solution, but AVATAR, Skylon and half a dozen proposed projects here in the US mange it quite well.

[Skipjack]

Because the source of money is my taxes. I would not mind (it would be just not my business) if they take money from different sources not from budget.

The budget for space exploration is tiny compared to the rest of the US budget. Using the commercial option (like SpaceX) would be a lot cheaper than the government launcher projects. So unless you want to cancel human space exploration all together, you better hope that SpaceX (and the other commercial providers) succeeds and the SLS gets cancelled, because it will save you a lot of tax money.

It is true, but the judge should be the free market: venture money -> R&D -> market. If there is a seemingly more efficient way to deliver the cargo to orbit and yet it is still below the radar of venture capitalist, it means advantage/risk ratio is too low; now they take the risk for my expenses paying from budget for space commercialization. It's a joke...

Space is a risky business with comparably small returns for the risk. You can still make a profit, but if you are planning to make tons of money, there are less risky options. Venture capitalists dont like risks. So they invest in stuff that makes them more money with less risk. It is that easy.
That does not mean that cheaper space access is without any purpose. It is the typical cat bites its own tail situation. The cheaper the access to space is the more clients will pop up. The more clients there are, the more money can be made with space launch and the more money will be invested in new technology, etc. The other way round, if space launch is expensive as it is now, there are very few that can afford it and that leans less clients. Less clients means less launches and that means less money spent, etc.
The investment by the government in the commercial launch providers is an attempt at breaking the circle and building a space industry and infrastructure. So far this has been working really well!
In addition to this there is the enthusiast Elon Musk who deliberately is trying to lower launch costs at the cost of his own profit (he is happy to have enough for R&D and keeping his company running, but does not intend to get rich from it himself... he already is).
It is actually interesting that there are people interested in investing in SpaceX and Elon Musk is considering taking the company public. But due to his personal agenda described above, he intends to keep the controling majority of the shares. This is why he has not done that yet.

[Skipjack]

You're tempting me to think it's a useful option, and it certainly is cool--has always been--but I just can't see adding the risk without huge savings

The difference is, I dont see it as much of a risk. If the alternative is to not reuse it, then you dont loose much if you try and accept a failure every so and so many launches (with more in the beginning and less once the routine comes in). By separating the crew from the rest of the vehicle you dont risk killing anyone either. Worst case is that you do a hard landing on the pad, or close to it and loose the vehicle. Even if you do, you might still be able to salvage it for parts and maybe get some useful data to improve the design.
If you loose it out at sea, you have very little chance of getting anything from it (as Musk had to find out).
I think that this was actually one of the mean reasons they decided to do this now rather than later. The whole retrieval from sea is way more complicated than they imagined, while companies like Armadillo, Masten and Blue Origin do vertical, tail first landings all the time.
The difference between a Xoie and a Falcon9 first stage is not THAT huge.
I do agree with your comment on the center of gravity on the F9 first stage, btw. But maybe they are going to change the shape a bit and make it slightly thicker at the bottom and shorter. More like the DC- X.
On the other hand... the BO design is not that short and stubby either.
Two rocket companies making the same mistake? I am not so sure it really is that big of a problem.

[GIThruster]

The difference is, I dont see it as much of a risk. If the alternative is to not reuse it, then you dont loose much

But that's not the issue. You're posing a false dilemma. They already plan to retrieve at sea. The question is whether they'll ever go the extra mile and try to land on land. BTW, this "extra mile" was the first thing to be scrapped with Orion, when the stick went overweight.

Bear in mind, that Falcon/Dragon is what Ares/Orion should have been.

Originally, Orion was slated to land on land just like any Russian mission. It is theoretically cheaper to retrieve on land. It does however require more and better engineering to retrieve on land and the launcher itself is less efficient.

Musk is just looking at history, picking and choosing the best of the best with a next gen launcher, made of the best materials. If he has enough margin, he can land on land just like the Russians. Landing the launch stages too, well that's a huge deal that most in the industry say is impossible.

[charliem]

I would glad to agree with you but today's technology is not up to make such enterprise economically viable. The situation may change dramatically once LENR is getting to be a real deal; with such tool, the space industry (in big sense) will indeed lead to a new golden age, in fact it may be the transition human civilization has never witnessed before.

And why LENR?

Lets forget that LENR might be a dead end. Why not wait until space anvils? Or until antimatter engines? Or warp engines? Or tele-transport?

I've heard many times from many people that R&D in certain areas is a waste of [their] money, but fact is that you never know what research is going to give useful results, and which is just going to expand our knowledge of what really is a waste.

From my point of view our (human's) history is proof enough that almost every cent spent in research, specially in the most basic fields (and I consider space a very basic field), is not an expense but an investment, and one with huge average returns.

If we can finance it without going broke, why not?

[stefanbanev]

I would glad to agree with you but today's technology is not up to make such enterprise economically viable. The situation may change dramatically once LENR is getting to be a real deal; with such tool, the space industry (in big sense) will indeed lead to a new golden age, in fact it may be the transition human civilization has never witnessed before.

And why LENR?

Lets forget that LENR might be a dead end. Why not wait until space anvils? Or until antimatter engines? Or warp engines? Or tele-transport?

I've heard many times from many people that R&D in certain areas is a waste of [their] money, but fact is that you never know what research is going to give useful results, and which is just going to expand our knowledge of what really is a waste.

From my point of view our (human's) history is proof enough that almost every cent spent in research, specially in the most basic fields (and I consider space a very basic field), is not an expense but an investment, and one with huge average returns.

If we can finance it without going broke, why not?

True, the judgment of what way is the most effective may differ so, let private money take the risk, not a government clerk should decide what is right/wrong, he/she has no skin in game...

[krenshala]

I would glad to agree with you but today's technology is not up to make such enterprise economically viable. The situation may change dramatically once LENR is getting to be a real deal; with such tool, the space industry (in big sense) will indeed lead to a new golden age, in fact it may be the transition human civilization has never witnessed before.

And why LENR?

Lets forget that LENR might be a dead end. Why not wait until space anvils? Or until antimatter engines? Or warp engines? Or tele-transport?

I've heard many times from many people that R&D in certain areas is a waste of [their] money, but fact is that you never know what research is going to give useful results, and which is just going to expand our knowledge of what really is a waste.

From my point of view our (human's) history is proof enough that almost every cent spent in research, specially in the most basic fields (and I consider space a very basic field), is not an expense but an investment, and one with huge average returns.

If we can finance it without going broke, why not?

True, the judgment of what way is the most effective may differ so, let private money take the risk, not a government clerk should decide what is right/wrong, he/she has no skin in game...

You are aware that SpaceX is doing its development with private funding, right? From your posts so far, you seem to be under the mistaken idea that SpaceX has been funded by NASA, when in fact it has only received money from NASA after having developed something that met certain progress milestones. To put it another way, SpaceX has no need of money from NASA for development, but is more than happy to accept payments for providing launch services (some of which are made when certain milestones are met).

[stefanbanev]

And why LENR?

Lets forget that LENR might be a dead end. Why not wait until space anvils? Or until antimatter engines? Or warp engines? Or tele-transport?

I've heard many times from many people that R&D in certain areas is a waste of [their] money, but fact is that you never know what research is going to give useful results, and which is just going to expand our knowledge of what really is a waste.

From my point of view our (human's) history is proof enough that almost every cent spent in research, specially in the most basic fields (and I consider space a very basic field), is not an expense but an investment, and one with huge average returns.

If we can finance it without going broke, why not?

True, the judgment of what way is the most effective may differ so, let private money take the risk, not a government clerk should decide what is right/wrong, he/she has no skin in game...

You are aware that SpaceX is doing its development with private funding, right? From your posts so far, you seem to be under the mistaken idea that SpaceX has been funded by NASA, when in fact it has only received money from NASA after having developed something that met certain progress milestones. To put it another way, SpaceX has no need of money from NASA for development, but is more than happy to accept payments for providing launch services (some of which are made when certain milestones are met).

I mostly reference to the "commercialization" NASA promotes. Any kind of subsidizing is a bad practice even if some cases are not too terribly bad.

[Skipjack]

They already plan to retrieve at sea. The question is whether they'll ever go the extra mile and try to land on land. BTW, this "extra mile" was the first thing to be scrapped with Orion, when the stick went overweight.

From what I understand, they are abandoning the concept, because they have not had much luck with it.
They also only planned for it to be an interim solution. It would never allow for the kind of low prices that Elon wants to achieve (100 USD/pound).

I would glad to agree with you but today's technology is not up to make such enterprise economically viable. The situation may change dramatically once LENR is getting to be a real deal; with such tool, the space industry (in big sense) will indeed lead to a new golden age, in fact it may be the transition human civilization has never witnessed before.

A technological breakthrough would indeed be good. I am not sure that it will be LENR, it could also be Polywell, or a DPF, or something else.
I do however think that even with todays technology it should be possible to reduce the price for a launch signifficantly.

I mostly reference to the "commercialization" NASA promotes. Any kind of subsidizing is a bad practice even if some cases are not too terribly bad.

You dont understand anything, do you?
NASA is not subsidizing, they are buying a service! The money they are paying is for buying a service from private companies.
It is NOT a subsidy. It also accelerates a process that is slowly happening anyway.

[charliem]

I would glad to agree with you but today's technology is not up to make such enterprise economically viable.

If we can finance it without going broke, why not?

True, the judgment of what way is the most effective may differ so, let private money take the risk, not a government clerk should decide what is right/wrong, he/she has no skin in game...

There are two big problems with leaving all research to private companies.

First, that some projects are simply too expensive for even the biggest multinational corporations.

Just think ISS. Until now its cost is about $100 billion, with B. That's too much, and not just for private capital, also for countries, even the richest ones.

Second, that private companies suffer from a bit of short-sight. If they cant see a profit at a quite short term (a few years at most), they are not prone to invest.

If not for governments the LHC would not exist, nor the Hubble Telescope, or most any other telescope, even on earth, research on certain areas of human health that have not a big profit promise either, a big chunk of oceanic research, etc.

The difference is, I dont see it as much of a risk. If the alternative is to not reuse it, then you dont loose much

But that's not the issue. You're posing a false dilemma. They already plan to retrieve at sea. The question is whether they'll ever go the extra mile and try to land on land. BTW, this "extra mile" was the first thing to be scrapped with Orion, when the stick went overweight.

Bear in mind, that Falcon/Dragon is what Ares/Orion should have been.

From my point of view NASA has a problem of philosophy. They evolve their plans from Up to Down. What I mean is that they tend to aim so high that there's no way that Congress will give them all the money they'd need, so they have to come down to more realistic goals. A consequence of that is that a tonne of money gets lost in the process, and the final result is not, by far, as economically efficient as it could be.

Private companies, such as SpaceX, develop plans with a Down to Up philosophy. They tend to start setting much modest goals (and fewer), and spend as little money as possible to achieve them. And if they succeed, before setting the next one, they ask themselves "what else can we do with what we already have?", and also "what's the next modest/cheap step we can take to enhance it to do more things?"

SpaceX and Elon Musk reminds me somewhat of Henry Ford. If not for his "Any customer can have a car painted any color that he wants so long as it is black" we would not have todays enormous catalog to choose our car from, most probably we'd have no catalog at all, at least for the not so wealthy.

[charliem]

A few more numbers.

According to the SpaceX web the present version of Falcon 9 develops a vacuum thrust of 1,110,000 lbf, and the Merlin 1C engine has a vacuum Isp of 304 s (so it burns 1656 kg/s of fuel).

Tom Mueller, VP of SpaceX, said two months ago that Merlin 1D has been designed to have a vacuum thrust of 155.000 lbf and an Isp of 310s (burning 227 kg/s each).

So, if we made a new Falcon9VTVL with these engines, total thrust (vacuum) would be 1,395,000 lbf, or a 25.7% more.

That increase in thrust allows a higher initial wet mass, from present model 333.4 t (metric) to 419.0 t. Most of the difference would be fuel.

Present version burns 1,656 kg/s of propellants for 172 s (total mass 280 t), and from it obtains about 5 km/s of delta-v (~1.8 goes to drag).

Falcon9VTVL would have to flight for 175 s to gain that same delta-v, and burn 350 t of fuel.

That means that just before separation Falcon9 weights 53 t, and the theoretical Falcon9VTVL would 69 t. That's 16 more tonnes.

How much delta-v can be squeezed from that? It depends of the stage 1 dry weight, and what portion of those 16 t is overweight from all the new hardware.

Stage 1 dry weight 10 t plus 16 t of fuel --> delta-v = 2.9 km/s

Stage 1 dry weight 12 t plus 14 t of fuel --> delta-v = 2.35 km/s

Stage 1 dry weight 15 t plus 16 t of fuel --> delta-v = 2.2 km/s

You don't need to keep much fuel for the final approach. To brake a vehicle of 17 t, falling at 250 m/s (the russiyanka rocket terminal velocity is 130 m/s, F9VTVL slender shape has to be more) with a Merlin 1D at full throttle, 9 seconds are enough (deceleration ~4 g) . A total of 2.0 t of propellants, equivalent to less than 400 m/s of delta-v.

So the difference between this 0.4 km/s and the above numbers is what is left for the braking maneuver after stages 1 and 2 separation.

Not much margin left, but of course these are only BOE calcs. It doesn't sound impossible.

[stefanbanev]

I mostly reference to the "commercialization" NASA promotes. Any kind of subsidizing is a bad practice even if some cases are not too terribly bad.

You dont understand anything, do you?
NASA is not subsidizing, they are buying a service! The money they are paying is for buying a service from private companies.
It is NOT a subsidy. It also accelerates a process that is slowly happening anyway.

To buy you need to have money to pay, the source of money makes the difference, paying by tax money to help to develop a private enterprise is a subsidizing.

>You dont understand anything, do you?

It's quite ironic; apparently it's impossible to make you type slower then you are able to think...

[GIThruster]

So, if we made a new Falcon9VTVL with these engines, total thrust (vacuum) would be 1,395,000 lbf, or a 25.7% more.

IIRC, the optimization in Merlin 1D is they extended the cone to get more thrust in vacuum. It would get less thrust at sea level so you don't want to use them for the first stage. They're intended for second stage only.

[charliem]

To buy you need to have money to pay, the source of money makes the difference, paying by tax money to help to develop a private enterprise is a subsidizing.

There are subsidies and there are purchases.

It is not the source of the money what marks the difference but, as you also say, the objective.

When you make a purchase the goal is to satisfy a need, and you do it searching for who can offer you the best buy (barring corruption or bad administration).

When you give a subsidy what you want is to promote some behavior you see of possible future benefit. At that moment the question of who can do it for less is secondary, because it's not clear yet what will be the cheapest avenue in the long run.

NASA does both.

The $500 M CCDev program is to promote the R&D of crew vehicles to LEO by private companies. Yes, that's a subsidy.

But the acquisitions of cargo capacity to different providers are clearly purchases, and if they pay in advance to speed up the last tests or tune up the vehicles to their like, even so, purchases still.