Yeah well we shall see when they come alive and what “reusability” actually means. Nothing is on their website. So if I reuse the astronaut couch does that make it a reusable vehicle? I know I exaggerate but you get the point. And as I already said multiple times at what cost? If cost is not an issue I can tell you we could build a darn good reusable vehicle with vertical landing and abort modes…

And wait until NASA or the FAA defines “reusability”…

Oh well…

1. HLV’s cost more to operate than existing vehicles because they are bigger and have low flight rates

2. Large payloads cost more per lb because of complexity

3. HLV payloads are too expensive and NASA can’t afford them. NASA can only fly one flagship per decade.

4. Only delusional fools think NASA funding will be increased

“The bigger the launcher the less it will cost per pound to orbit.”

As Vladislaw points out, you need to take into account more than just the marginal cost of the launcher.

Any government-run HLV is going to have a standing army of personnel that only supports the HLV, regardless how many times it launches (or not), or how much payload it sends to orbit. There are no funded programs, and since part of NASA’s budget will be consumed in just supporting the HLV program, NASA will have less budget to do real stuff in space. Not good.

Pretend like NASA has a set amount of money to work with (which it does) – how much could it do in space? With $10B, they could build part of an HLV (certainly not finish a 100 ton version). With that same money, they could put more than 1.6M lbs into LEO using existing launchers – that’s the equivalent to two of the current ISS.

We have the ability to put lots of mass into space, with money left over for payloads. Sure those payloads will be modular, but modular construction has lots of benefits, and along the way we’ll learn what the next larger size is we want to build.

There is nothing holding us back from doing stuff in space, except for lack of money – which is what HLV’s excel at sucking up and not returning.

Even then it seems doubtful. There are many potential forms of economies of scale and HLV is just one of them. Mass production would be enother economy of scale and so would massive reuse of a single reusable vehicle.

That is only true if the development costs are ignored. Once you factor in the all costs it changes the game. Also, unless you have a lot of payloads for the rocket to launch, it just sits there with an expensive ground crew doing nothing, again costs you are not accounting for.

The bigger the launcher the less it will cost per pound to orbit. The regulars here scream bloody murder when HLV’s are promoted and the simple truth of economy of scale is held up for others to see. All the advertising and double talk that flows onto this board when someone starts saying bigger is better is amazing. The more that goes up in a single launch, the cheaper it will be in the long run. The shuttle is held up as the argument against HLV but in fact the shuttle was payload, making the SRB’s and hydrogen second stage components the most fully evolved heavy lift hardware there is. Only idiots- or people trying to rip off the taxpayer, would just dump that infrastructure.

YOU need to focus on reality; as I just posted, it would take a 16 nozzle monster to equal the lift of two 5 segment SRB’s. The SRB’s are simple, resuable, and come loaded from the factory. The way you people talk about them you would think they are junk. They are not. They work. They are now, not 30 months from now (if you believe that figure).

“Actually yes “we” addressed some of these problems ann I believe their are AIAA papers of old available (for a fee?) or NASA papers.”

Good point. I guess I was talking about future vehicles and transportation systems, but the physics involved don’t change, only the attempted solutions.

“One of the problems with the Shuttle was that it had safe abort zones during launch, but not 100% coverage. Yes, low speed aborts for a winged vehicle should work, but what if you’re going at high speed?”

Not so easy even at low speed. For example max dynamic pressure usually is around Mach 1.3. Even Apollo had a major issue at this speed. Separation of the Apollo+LES (LEV) was not guaranteed and they had to enforce pitch to get it to go in a stable manner. A winged vehicle might very well rip off its wings under tremendous loads.

“It’s not that there isn’t an answer to these problems, but that we haven’t addressed them yet. I hope there is a solution, because I would rather land on wheels than water, but it’s cheaper to go back to the basics until we get enough traffic to warrant winged transportation.”

Actually yes “we” addressed some of these problems ann I believe their are AIAA papers of old available (for a fee?) or NASA papers.

“Since there is no Atlas “heavy” with 3 CBC’s, what are you talking about?”

ULA advertises the Atlas V Heavy on their website, so there is a product, but it is on hold for customer orders. They said they can have it ready for launch in 30 months, so it is a near-term solution when needed. But no one needs 32 ton to LEO capability (including the USAF), so they haven’t had a reason to finish it.

“If my math is correct it would require no less than 8 Atlas CBC’s to equal the thrust of 2 5 segment SRB’s.”

You need to focus on $/lb to orbit rather than just maximum thrust. Solid fueled motors have their uses, but liquid-fueled motors are more flexible, and are typically less costly for the end product, which is getting payload to orbit.

If you haven’t gotten the political message of the year, money matters, and Congress is getting ready to cut back on spending, so NASA will likely have to make do with less. SRB’s are not that solution.