Early CEV Mission

The CEV could be sent on a Lunar orbit mission in the near term.

Nath.

In article ,
"Blurrt" wrote:

The CEV could be sent on a Lunar orbit mission in the near term.

Nath.


Do we have a launch vehicle capable of putting a CEV (let's just say it
weighs about the same as a CSM) through TLI? If not, its deveolpment
would push back such a flight.

-Jonathan

--
Jonathan Drake, '04
Physics and Astronomy
Dickinson College

"Jonathan Drake" wrote in message
...
In article ,
"Blurrt" wrote:

The CEV could be sent on a Lunar orbit mission in the near term.

Nath.


Do we have a launch vehicle capable of putting a CEV (let's just say it
weighs about the same as a CSM) through TLI? If not, its deveolpment
would push back such a flight.

-Jonathan

Well, the vehicle could rendezvous with a boost stage. That seems a pretty
sensible option. Other than that, the mass of the CEV capsule could be
limited to 5-6 tonnes leaving 14-15tonnes for boost and transit stage/s. A
20tonne launch vehicle (Delta 4, proton etc)is all that is required (metric
units) whether it launches the vehicle in one or two parts.

Nathan

Jonathan Drake writes:

In article ,
"Blurrt" wrote:

The CEV could be sent on a Lunar orbit mission in the near term.

Nath.

Do we have a launch vehicle capable of putting a CEV (let's just say it
weighs about the same as a CSM) through TLI? If not, its deveolpment
would push back such a flight.

Even though I think the CEV's first missions will likely be to ISS,
there is no reason that you couldn't use two, or more, launches to go
to the moon (this is the EOR, or Earth Orbit Rendezvous approach which
was a possible approach for Apollo).

You use something like a Delta IV Heavy to put a CEV into orbit with a
transfer stage, then use one or more additional launches to put extra
fuel into orbit (or possibly entire transfer stages). Dock them
together (just as Mir and ISS are being assembled) and you're on your
way.

Jeff
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jeff findley wrote:

Even though I think the CEV's first missions will likely be to ISS,
there is no reason that you couldn't use two, or more, launches to go
to the moon (this is the EOR, or Earth Orbit Rendezvous approach which
was a possible approach for Apollo).

Okay, fair enough, but over the long term the cost of all these double
launches seems likely to exceed the development and subsequent operating
cost of a single heavy-lift ELV. How soon that point would likely be
reached would depend on a lot of unknowns, though.

-Jonathan

--
Jonathan Drake, '04
Physics and Astronomy
Dickinson College

Jonathan Drake writes:

Okay, fair enough, but over the long term the cost of all these double
launches seems likely to exceed the development and subsequent operating
cost of a single heavy-lift ELV. How soon that point would likely be
reached would depend on a lot of unknowns, though.

-Jonathan


The US is unlikely to be willing to fund a flight rate that will make a large
HLV competitive for some time. Delta cost a lot less per pound in orbit than
Titan IV for exactly this reason, and that doesn't count development costs.

Will Mclean

In article et,
Jonathan Drake wrote:
there is no reason that you couldn't use two, or more, launches to go
to the moon ...

Okay, fair enough, but over the long term the cost of all these double
launches seems likely to exceed the development and subsequent operating
cost of a single heavy-lift ELV. How soon that point would likely be
reached would depend on a lot of unknowns, though.

It's a long way out. The dominant costs of large launch systems are the
standing armies of people, who have to be paid even when they're not
working on a launch. The launch *rate* is almost irrelevant; doubling the
launch rate typically does not require anywhere near doubling the staff
(although it will require some small increases). Expended hardware is
not a big cost item, and costs there are partly canceled out by better
economics of larger production runs.

Costs depend a whole bunch on assumptions, but one analysis I've seen says
that it makes no economic sense to develop a launcher you don't intend to
use at least a thousand times before it's obsolete...
--
MOST launched 30 June; science observations running | Henry Spencer
since Oct; first surprises seen; papers pending. |

"McLean1382" wrote in message
...
Jonathan Drake writes:

Okay, fair enough, but over the long term the cost of all these double
launches seems likely to exceed the development and subsequent operating
cost of a single heavy-lift ELV. How soon that point would likely be
reached would depend on a lot of unknowns, though.

-Jonathan


The US is unlikely to be willing to fund a flight rate that will make a
large
HLV competitive for some time. Delta cost a lot less per pound in orbit
than
Titan IV for exactly this reason, and that doesn't count development
costs.

It also depends on how long a time frame you are talking.

While it's true that, long-term, developing a new heavy-lift ELV
may wind up being cheaper, if you don't have the money for
that, you have to take what you can get. Congress won't
give you $50B this year to develop your ELV; you'll get
$10B a year for the next 5 years instead. Now, at the end
of those 5 years, you could have a new ELV and no missions,
OR you could have flown several missions on existing ELVs.

If your goal is to fly missions ASAP and your funding is
limited, buying existing launch services is your only option.

Also, while such a heavy-lift ELV may be right-sized for
initial lunar missions, it may not at all be what you want
for lunar resupply, Mars missions, etc. The payoff on
the ELV only happens if you wind up using it a lot, and
15 years from now NASA's ELV requirements may be
very different.

Bruce

Jonathan Drake writes:

jeff findley wrote:

Even though I think the CEV's first missions will likely be to ISS,
there is no reason that you couldn't use two, or more, launches to go
to the moon (this is the EOR, or Earth Orbit Rendezvous approach which
was a possible approach for Apollo).

Okay, fair enough, but over the long term the cost of all these double
launches seems likely to exceed the development and subsequent operating
cost of a single heavy-lift ELV. How soon that point would likely be
reached would depend on a lot of unknowns, though.

Really? How much do you think it will cost to develop this new HLV?
It will surely be NASA specific, so plan on keeping the shuttle
(former Saturn V) facilities around to support this. The shuttle's
standing army will be needed too. If you do all this, where is the
money to develop the other hardware needed to get to the Moon?

The reality is that NASA can't afford another space shuttle sized
launch vehicle program.

It is much more likely that they can afford to buy commercial launches
as they are needed. As this is done, it will get Delta IV and Atlas V
to compete against each other and will hopefully end up lowering costs
for NASA and for anyone else who buys launches on these vehicles.
This is better for NASA and better for the commercial space industry
(e.g. comsats).

Jeff
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On 17 Jan 2004 11:16:05 -0500, jeff findley
wrote:

The reality is that NASA can't afford another space shuttle sized
launch vehicle program.

Correct, but I do not foresee moving to the Delta IV or Atlas V
myself, when these launchers do not seem powerful enough.

Since I would envision a larger Moon landing capsule design myself,
then launch mass I would estimate as between 12 to 30 tons. Since NASA
is likely to want to move cargo with this same launch system, then the
larger size is preferred.

So those rockets you mention are ideal for satellite launches, but I
doubt even ESA's 12 ton launcher is good enough for putting lots of
mass on the Moon.

And so out of the same budget that NASA builds the CEV I expect they
would build a new launcher of around 20 to 30 tons. Most of all I
would expect NASA to use those in-development RS-84 engines.

I expect that a lot of their current launch and support system could
be got rid of, but they would need a smaller facility, even if they
contract this out.

Best idea, when there may be a commercial use for a reusable 15 to 30
ton launcher.

Still, lets see what designs NASA can rally up.

It is much more likely that they can afford to buy commercial launches
as they are needed.

There is no current commercial reason to put lots of mass on the Moon,
which is why no existing launcher is really good enough.

As this is done, it will get Delta IV

Delta IV heavy is 13.2 metric tons to LEO (and not the Moon!).

Possible, if they wish a really small craft, but even NASA's CEV promo
tape envisions something much larger.

and Atlas V

Atlas V heavy is 11.4 metric tons to LEO.

I just cannot envision building a Moon Base using these launchers,
when you will need many more launches than going with the RS-84 route.

In other words let me know when we have the Delta V and Atlas IV.

to compete against each other and will hopefully end up lowering costs
for NASA and for anyone else who buys launches on these vehicles.

I am sure that you can work out for yourself how many tons these two
launchers can put on the Moon, where I just do not see that this is
good enough.

So I would save these rockets for launches to the ISS, if the CEV fits
in these weight limits of course.

This is better for NASA and better for the commercial space industry
(e.g. comsats).

NASA I am already sure has other plans.

Cardman
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