No need for HLLVs

"Henry Spencer" wrote in message
...
In article ,
DGH wrote:
1) Development costs ~ Almost all the designs being proposed for heavy
lift
are using existing flight tested components.
This should cause major reductions in development costs. It should cost
around what the EELVs did to develop.

Depends on how it is done, and by who. NASA's estimate for development of
Shuttle-C, a decade ago, was several times that.

Anything is possible.


2) Cost ~ The cost seems a little high based on that we already know the
cost of the individual components.

It is by no means a foregone conclusion that we already know the costs of
the components. That depends on the *choice* of components.

Moreover, especially for the low launch rate one would expect from an
HLLV, component cost is almost irrelevant. What matters is the size of
the standing army, both at the factory and at the launch site, because
they have to be paid no matter how much or how little they launch.

Agree. That is why I suggest it only when the launch model gets high enough.
I have said before the cut off point seems to be around 24 Heavy EELVs
If we want less then a million pounds a year to orbit for the Moon Mission
then forget any Heavy lift.



3)Market ~ First the average satellite mass has been increasing for some
time and is unlikely to stop doing so. The use by NASA of this rocket
peaks
in the Early 2020's so we are talking about the Market in the late 2020's
and beyond commercial and Military satellites should be very large by
then.

Maybe, and maybe not. Such predictions are rather uncertain... as are
predictions of competing systems that might develop in those twenty years.

Third the most common design of these rockets without the shuttle solids
are
very similar to a Delta IV Heavy which a market already exists for.

The only existing market for Delta IV Heavy, if I recall correctly, is two
launches for the NRO. Hardly a solid customer base.

The same weight class includes the Araine 5, Atlas Heavy and just a little
lower Sea Launch.
These vehicles make up a large percentage of the market in dollar terms.


4)Orbital assembly ~ ISS strikes again. Those who fail to learn from
history are bound to repeat it.

Ah yes, the Wile E. Coyote approach to engineering: if it doesn't work
once, the whole approach must be infeasible, so throw it out and try
something entirely different, rather than trying to debug it.

No just simple logic. One part would be automated assembly the other would
be less assembly.
At the higher end even with 150,000 pound heavy lift you still have you
would still have 20 launches.
That would still be a lot of orbital assembly.


The main thing we learn from the history of the shuttle and ISS is not to
put JSC in charge of a major space project. (MSC was a much more capable
place, but it's gone.)

This would take between 24 and 40 EELV Heavy launches a year. The high
end
would take many more EELVs then the plants are designed to produce...

We could, of course, enlarge the plants, or invest in automation of the
existing ones (Khrunichev goes from sheet metal to a finished Proton in
eleven months, something neither EELV plant can match). Either is likely
to be cheaper than developing an HLLV. In fact, changes like *these*
could probably be privately financed, if the government was willing to
commit to volume purchases of rockets.

Since they would never know when the contract might end it would be real
hard to get them to build another plant.
Traditionally they design a new rocket when this happens. A three engine
version would be under current circumstances most likely since it has engine
out capability for man rating an item which is already going to have funds.


It would probably be cheaper to look at minor improvements to the existing
rockets.
The MB-60 and RL-60 come to mind both will give nice additional capacity.
Another option might be reuse of rocket engines.

I do not rule out an EELV only system.
I am just not ready to rule out a HLV assisted system either.
Both have advantages.
Both have disadvantages.
As we move forward and the plan takes shape we will then see which is better
for that plan.

clip

This would take between 24 and 40 EELV Heavy launches a year. The high
end
would take many more EELVs then the plants are designed to produce...

We could, of course, enlarge the plants, or invest in automation of the
existing ones (Khrunichev goes from sheet metal to a finished Proton in
eleven months, something neither EELV plant can match). Either is
likely
to be cheaper than developing an HLLV. In fact, changes like *these*
could probably be privately financed, if the government was willing to
commit to volume purchases of rockets.

John Karas of Lockheed said in his recent Senate testimony that vehicles
carrying up to 75 tons are compatible with current EELV infrastructure (I
suppose he's only speaking for the Atlas infrastructure).
http://commerce.senate.gov/hearings/...75&wit_id=3363

That should be enough for moon flights, with only limited EOR.


The 75 ton figure seems a little high without new designs but not new
engines.
Multi-engine versions could do 75 tons.
Much more powerful second stages could be a big boost as well.
Dual MB-60 or RL-60 upper stages would offer very large boosts especially if
combined with a RL-10 upper stage.

I really wish they had put up his exhibits.

Derek Lyons wrote:
Sander Vesik wrote:
Couldn't one build "containerised" HLLV? You know, figure out how many
launches you are going to do (max) in the next 15-20 years, design a HLLV
that has a storage life of 25 years,

Essentially no. It costs a great deal to design a booster with any
significant shelf life. The USAF/USN have spent a great pile of money
on doing exactly that, and even they don't trust a bird longer than
about 2-3 years without major inspections and maintenance.

In that case, they should be buying the know-how from the people who did
did the UR-100N (aka SS-19) ICBM. It appears to provide for at least 25
year successful storage life.


D.

--
Sander

+++ Out of cheese error +++

Derek Lyons wrote:
Sander Vesik wrote:
Couldn't one build "containerised" HLLV? You know, figure out how many
launches you are going to do (max) in the next 15-20 years, design a HLLV
that has a storage life of 25 years,

Essentially no. It costs a great deal to design a booster with any
significant shelf life. The USAF/USN have spent a great pile of money
on doing exactly that, and even they don't trust a bird longer than
about 2-3 years without major inspections and maintenance.

Remember that unlike milkitary, you can postpone pumping fuels until
you need them. There is no need for a 1 minute launch readyness.


D.

--
Sander

+++ Out of cheese error +++

Joe Strout writes:

The Moon should be developed because it's the obvious next step in
learning to live off Earth, and a source of raw materials for use in
cislunar space; not because it helps us go visit the setting of Edgar
Rice Burroughs novels.

Of course. But should it be developed by socialistic government space
agencies, or by private industry?

Perhaps the government should do research and "exploration" while
private industry takes the results of that and figures out how to make
a profit.

Jeff
--
Remove "no" and "spam" from email address to reply.
If it says "This is not spam!", it's surely a lie.

Sander Vesik writes:
Couldn't one build "containerised" HLLV? You know, figure out how many
launches you are going to do (max) in the next 15-20 years, design a HLLV
that has a storage life of 25 years, build a launch facilitythat lets you
simply drop the conatiner off the transport, install an upper stage with
satellite and launch. This will let you just build a large patch of them
and not maintain any kind of standing army or production facilities at all.

You mean like we did with the Saturn V? The problem with this
approach is that it is absolutely not sustainable. Once your HLLV
supply is gone, you're done, unless you're willing to pay for the huge
startup costs to build more (you've got to re-hire and re-train your
standing army of HLLV production workers, even if you have paid keep
the tooling in storage).

The only way to make access to space sustainable, is to look at it as
a process that is continuous, not a series of events. If you take
this approach, you want your highly trained workers to be productive,
with little down time, as well as minimizing the size of that "standing
army" of workers. Note that this is very hard to do with any sort of
low flight rate vehicle.

Jeff
--
Remove "no" and "spam" from email address to reply.
If it says "This is not spam!", it's surely a lie.

George William Herbert wrote:
DGH wrote:

Other:
1) Less dependable launches ~ 1 in 3 is kind of crazy IMO but a 5% failure
rate would not be bad for bulk cargo.


Why would any failure rate be bad for bulk cargo, which costs
essentially nothing compared to any credible next couple of
decades space access system launch costs? Nobody is going
to feel badly if you scatter LOX or liquid hydrogen or water
or a load of sandwiches and soup and toilet paper across the
middle of the ocean.

Delivered price = launch cost / reliability

If a rocket with 66.7% reliability costs half what the 95%
reliable rocket does, you save money, significantly.
If a rocket with 50% reliability costs a quarter of what
the 95% reliable rocket does, you save more money than that.

The actual cost / reliability tradeoffs are more complicated than
that and have not been analyzed in as great depth as I would
like... not enough for a AIAA paper, but good enough for some
usenet arguments. I believe that going from 97% to 90% reliability
is likely to save between 35 and 45% of the cost, and from 90% to 75%
reliability is likely to save 45-65% of the cost. Those *clearly*
are net wins for lower reliability in bulk materials transport.

It seems to me that cheaper, less reliable rockets would eventually
result in more reliable rockets.

Ford or GM didn't build more reliable cars by having engineers second
guess every failure that had a remote possibility of occuring. They
built more reliable cars by building many thousands of them and learning
from experience.

--
Hop David
http://clowder.net/hop/index.html

jeff findley wrote:
Still, the pieces are transported commercially. The construction
companies typically don't have to build their own trucks to move
oversized loads.

Indeed. There is a whole specialized industry dedicated to moving
overweight/oversize parts.

D.
--
Touch-twice life. Eat. Drink. Laugh.

Sander Vesik wrote:

Derek Lyons wrote:
Sander Vesik wrote:
Couldn't one build "containerised" HLLV? You know, figure out how many
launches you are going to do (max) in the next 15-20 years, design a HLLV
that has a storage life of 25 years,

Essentially no. It costs a great deal to design a booster with any
significant shelf life. The USAF/USN have spent a great pile of money
on doing exactly that, and even they don't trust a bird longer than
about 2-3 years without major inspections and maintenance.

In that case, they should be buying the know-how from the people who did
did the UR-100N (aka SS-19) ICBM. It appears to provide for at least 25
year successful storage life.

Got a cite on that (other than a propoganda site)? (And be sure
that's 25 years in cold storage, not 25 years in maintained storage.)

D.
--
Touch-twice life. Eat. Drink. Laugh.

Sander Vesik wrote:

Derek Lyons wrote:
Sander Vesik wrote:
Couldn't one build "containerised" HLLV? You know, figure out how many
launches you are going to do (max) in the next 15-20 years, design a HLLV
that has a storage life of 25 years,

Essentially no. It costs a great deal to design a booster with any
significant shelf life. The USAF/USN have spent a great pile of money
on doing exactly that, and even they don't trust a bird longer than
about 2-3 years without major inspections and maintenance.

Remember that unlike milkitary, you can postpone pumping fuels until
you need them. There is no need for a 1 minute launch readyness.

Doesn't have anything to do with fuels and fuelling. It has
everythign to do with the fact that components and structures age,
even when sitting in storage.

If your stored birds require significant work before use, then you
have lost any advantage you have over JIT production.

D.
--
Touch-twice life. Eat. Drink. Laugh.