TGD(ver 1.0) Waste of Time

Al Globus wrote:

> Ian Woollard wrote:
>> Al Globus wrote:
>>> Ian Woollard wrote:
>> Yes, but costs to launch go down greatly with launcher size. Saturn V
>> was rather a lot bigger. Launchers are getting bigger aren't they?
>
> I believe the shuttle has the greatest capacity to LEO, and it's less than Saturn V, so
> no, they aren't.

Absolutely. Space Shuttle is a highly capable, highly advanced space vehicle.
It's a source of great national pride, and rightly so.

Not cheap though.

When I formed the opinion I now hold (and unlike most people I know I am
quite willing to change my opinion on something) I checked out the data
on launch payloads and costs. I threw away all the expensive ones- I
figured they'd screwed up somehow- space launch is HARD after all
and in any case I was trying to minimise the cost of a project I
was working on (landing 10 tonnes of hardware on the moon).

I then stared at the numbers and noticed a weak correlation with
launch size. In particular, the cheapest was Proton V with a launch
cost of $2600/lb which was also amongst the biggest.

I've since read up on the theory behind launch costs, it looks like
everything else being equal (which it never is) big rockets are
cheaper than little ones. This is spectacularly true at the small
payload sizes. When you reach Space Shuttle sizes it isn't quite
so obvious, then again there's probably only about 4 launchers of
that weight class including Saturn V.

My theories about why both the Space Shuttle and ESA launchers are
similarly priced are:

a) they address a similar market (ESA could afford to price its
launcher upto the space shuttle prices because there's been little
competition.

b) they use hydrogen (hydrogen has required some massive development
costs, and still has technical disadvantages; and it turns out that
the supposed advantages of hydrogen aren't there once you plug it
into a complete launch system, or are greatly reduced, I'd have
naively expected many times more payload)

c) they are projects run by western governments (Soviet block governments
tend to be more efficient than western governments, but not nearly
as efficient as western companies!)

d) this is a weird one- they're kinda similar! Sure, the ESA has no
wing, but they both have 3 sets of rockets, the central one burns
hydrogen, with two booster rockets either side to allow them to
make orbit. There's a reason for that too. ESA were trying to copy
the Space Shuttle (Hermes).

>>>> Tourism is ~15 years away, if I am right.
>>>
>>> I wish you were right, but I don't see a shred of evidence for a tourism business
>>> outside of people with literally millions to spend on a trip to space.. The only
>>> hope I see for middle-class tourism is NASA's official goal of a few hundred
>>> dollars/lb to LEO by 2020 or so with one failure in 10,000 flights. If this goal
>>> were reached, tourism should work. However, I don't see a development path that
>>> will get us there. Hopefully am wrong.
>>
>> Isn't that the same goal they had for the Space Shuttle?
>
> No. Cost goals for the shuttle were $500/lb in 1980 dollars and one failure in 100,000
> flights. The shuttle missed these goals by over an order of magnitude in cost and three
> orders of magnitude in reliability. Nonetheless, the space shuttle is by far the most
> capable launch vehicle in the world.

Undoubtedly. The space shuttle is like a Ferrari; overpriced, somewhat unreliable
(although not by space standards!) and excellent performance. And I want one
of each ;-)

>> NASA don't
>> care about cheap launch.
>
> There's a difference between failing to achieve your ambitious goals and not caring. In
> my experience, many people at NASA do care about cheap launches, although there has been
> little success.

Yes. I'm more talking not about what the people that make up NASA want; but
how NASA as a whole behaves. It's a subtle distinction. NASA behaves
as if space costs are irrelevent. NASA people state that they want to reduce
costs, but NASA doesn't do so. NASA people aren't lying either. They may
well be trying to do so. But if the political will isn't there, or doing so
would damage NASA then they may be organisationally unable to act in a way that
they may genuinely wish to.

For instance if a big dumb booster really would slash costs by an order of
magnitude would NASA go for it? Doubtful. Going to a big dumb booster would
also slash the profits of the associated companies. The politics would be
terrible also, NASA is supported by pork barrel politics. There might even
be national esteem issues of large bruteforce low tech throwaway rockets
compared to reusable, cutting edge hydrogen, with these amazing tiles...

There is evidence that the associated companies deliberately intervened
in the studies of big dumb rockets. Whether they intervened to provide
technical assistance or provide apparent technical assistance but
scupper the whole thing is unclear; but I strongly suspect the latter.

Whether a big dumb rocket would actually cut costs; probably, but of
course till someone actually tries it...

>> Or more accurately the associated companies
>> around NASA don't care about cheap launch. They like it just
>> fine really expensive with them raking off a percentage.
>
> I think there may be some truth to this. However, in the current launch market people
> are cutting margins to the bone because of the extreme competition. Most of the fat is
> either gone or will be gone soon, so current commercial prices are a pretty good
> indication of real cost.

Yes. But there is a difference between real cost that was achieved and
real costs that can be achieved or even real costs that have been
achieved elsewhere.

>> Why else
>> is the space shuttle the most expensive launcher ever per pound
>> (ignoring the small launch systems)?
>
> Other possibilities: It's the only re-usable launch vehicle, it's man-rated, and
> operations are quite different than other vehicles. The shuttle has a 1% failure rate
> while commercial launchers have about a 7% failure rate. At these levels, additional
> reliability is pretty expensive. Also, the shuttle is the *least* expensive launcher in
> volume per lb., so your choice of measurement affects the analysis.

I don't consider re-usability to be much of a plus, but other
than that its all very true. Volume is definitely useful for
some payloads, but in general I have a feeling that weight is
more critical; many things can fold, but things never get
heavier when they reach orbit.

> Note that Orbital Sciences was able to create a new
> company, break into the aerospace market (including launchers), and become a major player
> over the last 10 or 15 years. It's not impossible.

Glad to hear.

> --
> Al Globus
> aglobus@..., (650) 604-4404
> http://www.nas.nasa.gov/~globus/home.html

--
- Ian Woollard (ian.woollard@...)

"Is a planetary surface the right place for an expanding technological
civilization?"
- Gerard O'Neill