Ares vs Delta or Atlas

Ian Parker wrote:

:On 31 Dec 2008, 22:16, Fred J. McCall wrote:
: Ian Parker wrote:
:
: :On 31 Dec, 20:08, Fred J. McCall wrote:
: : Ian Parker wrote:
: :
: : :On 31 Dec, 16:01, Frogwatch wrote:
: : : So, why not upgrade the Delta or Atlas instead of building Ares 1 or
: : : 2. *Are the solid boosters really more reliable and safe? *Could an
: : : upgraded Delta or Atlas launch Orion without huge changes to the
: : : launch support facilities?
: : :
: : : Please, no replies from Kt Or Guth
: : :
: : :SATURN my friend if they havn't destroyed the blueprints.
: : :
: :
: : Blueprints are the least of your problems if you want to replicate
: : Saturn V. *You have to build all new tooling, find or rebuild sources
: : for all those 1960's components, etc.
:
:In many cases you could have close equivalents.
:

"Close equivalents" requires a redesign and recertification. Have you
ever designed and built ANYTHING?

:
: :
: : Trying to just repeat the past is generally not a good approach. *We
: : could build a much better Saturn V these days if a Saturn V is what is
: : wanted.
: :
: :
: :Futurologists have things called S curves.
: :
:
: 'Futurologists' are generally loony.
:
:
:Are your predictions any better?
:

Yes.

:
: :It is NOT a different concept, like a
: :nuclear rocket, an ion drive or even the use of AI to mine the Moon/
: :Astreroids would be.
: :
:
: Yes, it is QUITE a 'different concept' from Saturn V. *In this case
: 'different' doesn't necessarily mean 'better'.
:
:
:If it is NOT better why not just build Saturn?
:

Because you can't. You either redesign for a new 'Saturn V' or you
start from requirements and design something better.

: A couple more hints for you:
:
: 5) Using multiple vehicles to mount a single Moon mission is a
: 'different concept' from the single vehicle 'direct' approach used by
: Saturn V.
:
: 6) Building these large solids and putting people on them is a
: 'different concept' and is currently totally untested.
:
:But Ares has the same role as Saturn.
:

No it doesn't.

:
:The payload of the largest Ares
:is even a bit bigger than that of Saturn.
:

Except, of course, it isn't allowed to carry people.

:
:You are right in saying that
:Apollo was one rocket and consellation involves many modules going to
:the Moon. However the propellor Ares is little different from aturn
:and is likely to be a lot more expensive.
:

To recreate Saturn V would probably be MORE expensive than Ares. To
create an equivalent would probably be cheaper.


--
"The reasonable man adapts himself to the world; the unreasonable
man persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man."
--George Bernard Shaw

On Jan 3, 6:19*am, Fred J. McCall wrote:
Ian Parker wrote:

:On 31 Dec 2008, 22:16, Fred J. McCall wrote:
: Ian Parker wrote:
:
: :On 31 Dec, 20:08, Fred J. McCall wrote:
: : Ian Parker wrote:
: :
: : :On 31 Dec, 16:01, Frogwatch wrote:
: : : So, why not upgrade the Delta or Atlas instead of building Ares 1 or
: : : 2. *Are the solid boosters really more reliable and safe? *Could an
: : : upgraded Delta or Atlas launch Orion without huge changes to the
: : : launch support facilities?
: : :
: : : Please, no replies from Kt Or Guth
: : :
: : :SATURN my friend if they havn't destroyed the blueprints.
: : :
: :
: : Blueprints are the least of your problems if you want to replicate
: : Saturn V. *You have to build all new tooling, find or rebuild sources
: : for all those 1960's components, etc.
:
:In many cases you could have close equivalents.
:

"Close equivalents" requires a redesign and recertification. *Have you
ever designed and built ANYTHING?

:
: :

i get reading this thread and thinking costs, when the delta/atlas
was 1st contracted they where to cost around 100 million, last i heard
it was costing over 200 million per launch, where the shuttle's
boosters cost less than 50 mill, and when the concept of building the
stick launch vehicle was considered, getting a man rating for maned
flight was part of the consideration, as the shuttles solid boosters
had a launch record, and delta/atlas had none.
back to the ares, if your going to bundle 3 or 4 of the delta/atlas
systems together to launch the equivalent mass of the 3rd stage of a
Saturn 5 (around 75 tons) you could also use a 3 engine version of the
"shuttle c" ( no re-entry cargo version) to get the same mass into
orbit, both systems are derivatives of currently operational launch
vehicles. and would most likely have quite similar development costs.
unless you where to just strip a shuttle, as 2 of the currently flying
shuttles where made out of spare parts.
the Saturn 5 was expensive to build, the reusable shuttle idea
didn't prove to be more cost effective, using the delta/atlas systems
to recreate a system similar to the Saturn 5 will most likely have the
same cost, while it would be great to have a NASA/millitary
cooperation prove to be less costly, Historically wasn't that the
Saturn 5 ?

On 3 Jan, 15:16, wrote:
On Jan 3, 6:19*am, Fred J. McCall wrote:





Ian Parker wrote:

:On 31 Dec 2008, 22:16, Fred J. McCall wrote:
: Ian Parker wrote:
:
: :On 31 Dec, 20:08, Fred J. McCall wrote:
: : Ian Parker wrote:
: :
: : :On 31 Dec, 16:01, Frogwatch wrote:
: : : So, why not upgrade the Delta or Atlas instead of building Ares 1 or
: : : 2. *Are the solid boosters really more reliable and safe? *Could an
: : : upgraded Delta or Atlas launch Orion without huge changes to the
: : : launch support facilities?
: : :
: : : Please, no replies from Kt Or Guth
: : :
: : :SATURN my friend if they havn't destroyed the blueprints.
: : :
: :
: : Blueprints are the least of your problems if you want to replicate
: : Saturn V. *You have to build all new tooling, find or rebuild sources
: : for all those 1960's components, etc.
:
:In many cases you could have close equivalents.
:

"Close equivalents" requires a redesign and recertification. *Have you
ever designed and built ANYTHING?

:
: :

* *i get reading this thread and thinking costs, when the delta/atlas
was 1st contracted they where to cost around 100 million, last i heard
it was costing over 200 million per launch, where the shuttle's
boosters cost less than 50 mill, and when the concept of building the
stick launch vehicle was considered, *getting a man rating for maned
flight was part of the consideration, as the shuttles solid boosters
had a launch record, and delta/atlas had none.
* *back to the ares, if your going to bundle 3 or 4 of the delta/atlas
systems together to launch the equivalent mass of the 3rd stage of a
Saturn 5 (around 75 tons) you could also use a 3 engine version of the
"shuttle c" ( no re-entry cargo version) to get the same mass into
orbit, both systems are derivatives of currently operational launch
vehicles. and would most likely have quite similar development costs.
unless you where to just strip a shuttle, as 2 of the currently flying
shuttles where made out of spare parts.
* *the Saturn 5 was expensive to build, the reusable shuttle idea
didn't prove to be more cost effective, using the delta/atlas systems
to recreate a system similar to the Saturn 5 will most likely have the
same cost, while it would be great to have a NASA/millitary
cooperation prove to be less costly, Historically wasn't that the
Saturn 5 ?- Hide quoted text -

In fact Saturn 5 had the lowest cost/Kg. The fact of the matter is
that NASA thought that a windeg spacecraft was the way to go. Now they
think it isn't.

If you want a launcher for heavy indivisible loads, Saturn has nevrer
been beaten. Anything new is going to look very like Saturn and cost
probably more. The deeper question is do we need heavy indivisible
loads. Are there other ways of looking at the problem.


- Ian Parker

Quadibloc wrote:

It may well be a single rocket engine, but with four chambers, are
there now four chances for the combustion to become unstable? Or, on
the other hand, since it is very difficult to scale up a rocket
combustion chamber, is a design with multiple chambers a safer option?


They went with that design on the RD-107/08 series of engines on the R-7
ICBM entirely due to the combustion instability problem they were
running into with trying to build a single-chambered engine of that thrust.
Behold one of the great flops of Soviet space design; the giant
single-chambered RD-105 engine:
http://www.russianspaceweb.com/rd105_r7_2.jpg
http://www.astronautix.com/engines/rd105.htm
With its long cylindrical combustion chamber and conical engine bell,
that thing made the A4/V2 engine look like a pretty sophisticated piece
of design.

Pat

Just look at what you are saying Fred. I am sure most people would
come to the conclusion that this was no a scientific discussion group.

BTW - You seem to me to be hazy on the basic laws of dynmamics. What I
said on fragmented telescopes and ion station keeping was absolutely
correct. You rubbished it out of total ignorance.

I also feel that we should be thinking of ultra stability when we
xconsider future telescopes.

But , we are not a scientific group - Are we?


- Ian Parker

As I said I now know what the Iraqis were up against.

Once again we see the total removal of context that indicates an
A.S.S. reset of 'Ian Parker'.

Let's keep in mind Ian's original statement - that in a rocket
"Stability is produced by control of the fuel pump."

I pointed out to him just how wrong that statement is. Hence his
removal of all context.

Now, let us continue....

Ian Parker wrote:
:
:Just look at what you are saying Fred. I am sure most people would
:come to the conclusion that this was no a scientific discussion group.
:

Perhaps 'most people' in your world, Ian. But you're a loon.

:
:BTW - You seem to me to be hazy on the basic laws of dynmamics.
:

Many preposterous things "seem" to be true to you. You "feel" the
correctness of much absolutely barmy material.

:
:What I
:said on fragmented telescopes and ion station keeping was absolutely
:correct. You rubbished it out of total ignorance.
:

I didn't 'rubbish' it. It was rubbish to start with, as others
pointed out to you.

:
:I also feel that we should be thinking of ultra stability when we
:xconsider future telescopes.
:

There you go 'feeling' again. Try 'thinking', instead. You might
like the change, should you ever manage to actually do it.

:
:But , we are not a scientific group - Are we?
:

You certainly aren't.

:
:As I said I now know what the Iraqis were up against.
:

Of course you do.

You don't know anything about anything, Ian, if the public record is
any indicator.


--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
-- Thomas Jefferson

"Ian Parker" wrote in message
...
Stability is produced by control of the fuel pump. A single engine
means that the punping system is shered between 4 combusion chambers.

Ares, as I understand it, is unstable because acceleration leads to
greater pressure in the pump(s). This means more fuel goes through
leading to a faster acceleration. The control system throttles back,
but time delays lead to an oscillation.

What you're describing is POGO, which can afflict liquid fueled rocket
stages. POGO is relatively easily solved by dampers in the fuel/oxidizer
feed lines. POGO solutions eliminate oscillations at the source (the
pumps/engines).

But what Ares suffers from is thrust oscillation caused by its *solid*
fueled rocket stage. This is an entirely different problem than POGO and is
absolutely not easily solved. NASA's current solutions for Ares I mitigate
the effects of thrust oscillation on the upper stage and Orion, they don't
eliminate thrust oscillation in the solid stage.

Anyone who is defending Ares I and points to POGO solutions on Saturn and
says, "look we've solved these sorts of problems before" is being
disingenuous at best and an outright liar at worst.

Jeff
--
"Many things that were acceptable in 1958 are no longer acceptable today.
My own standards have changed too." -- Freeman Dyson

On Mon, 5 Jan 2009 10:01:16 -0500, in a place far, far away, "Jeff
Findley" made the phosphor on my monitor
glow in such a way as to indicate that:


"Ian Parker" wrote in message
...
Stability is produced by control of the fuel pump. A single engine
means that the punping system is shered between 4 combusion chambers.

Ares, as I understand it, is unstable because acceleration leads to
greater pressure in the pump(s). This means more fuel goes through
leading to a faster acceleration. The control system throttles back,
but time delays lead to an oscillation.

What you're describing is POGO, which can afflict liquid fueled rocket
stages. POGO is relatively easily solved by dampers in the fuel/oxidizer
feed lines. POGO solutions eliminate oscillations at the source (the
pumps/engines).

But what Ares suffers from is thrust oscillation caused by its *solid*
fueled rocket stage. This is an entirely different problem than POGO and is
absolutely not easily solved. NASA's current solutions for Ares I mitigate
the effects of thrust oscillation on the upper stage and Orion, they don't
eliminate thrust oscillation in the solid stage.

Anyone who is defending Ares I and points to POGO solutions on Saturn and
says, "look we've solved these sorts of problems before" is being
disingenuous at best and an outright liar at worst.

I think that in Ian's case, he's simply uninformed, nuts, and stupid.
But other than that, he's great...

"Rand Simberg" wrote in message
...
On Mon, 5 Jan 2009 10:01:16 -0500, in a place far, far away, "Jeff
Findley" made the phosphor on my monitor
glow in such a way as to indicate that:
But what Ares suffers from is thrust oscillation caused by its *solid*
fueled rocket stage. This is an entirely different problem than POGO and
is
absolutely not easily solved. NASA's current solutions for Ares I
mitigate
the effects of thrust oscillation on the upper stage and Orion, they don't
eliminate thrust oscillation in the solid stage.

Anyone who is defending Ares I and points to POGO solutions on Saturn and
says, "look we've solved these sorts of problems before" is being
disingenuous at best and an outright liar at worst.

I think that in Ian's case, he's simply uninformed, nuts, and stupid.
But other than that, he's great...

While true, it's easy to see how the uninformed can be misled when even Dr.
Griffin has given talks which describe Saturn V POGO followed by a
discussion of Ares I thrust oscillation.

http://www.nasa.gov/pdf/222994main_B..._17_Apr_08.pdf

Similar disinformation here (near the end of the paper):

http://ntrs.nasa.gov/archive/nasa/ca...2008018688.pdf

Such "official" disinformation does nothing to eliminate the confusion that
some have between (liquid fueled) POGO and (solid fueled) thrust
oscillation.

Jeff
--
"Many things that were acceptable in 1958 are no longer acceptable today.
My own standards have changed too." -- Freeman Dyson

Pat Flannery wrote:
:
:Fred J. McCall wrote:
: :If you did make a rocket engine that, say, used two separate turbopumps
: :to drive its four combustion chambers... yeah, I'd agree to that being
: :two separate rocket engines despite what the designers called it or how
: :the wiring or plumbing on it worked.
: :
:
: Why? Just based on the number of pumps? We just saw that break down
: for your automotive example. Is it any better definition here?
:
:
:It didn't break down for my automotive example.
:

It certainly did initially, where you started out saying that if there
was a single fuel pump then it was a single engine (like your 'single
turbopump' argument for rocket engines). Then I pointed out that a
fuel injected engine with multiple fuel pumps would not necessarily be
too odd, at which point you switched to 'more than one engine block'.

:
:If the Cadillac V-16 engine consisted of two separate Cadillac V-8
:engines connected to a single transmission system, I would have no
roblem at all calling it a two-engine system.
:But it used a single carburetor and electrical system connected to all
:16 cylinders mounted in a single engine block.
:Even if it had consisted of two separate V-8 engine blocks connected to
:a single drive shaft front-to-back but using a single electrical system,
:distributer to fire the spark plugs appropriately, and carburetor to
:feed all sixteen cylinders the correct fuel-air mixture - as well as the
:timing gears that opened and closed all sixteen intake and exhaust
:valves at the appropriate times to make the engine work properly, then
:it's a single engine.
:Split the two engine blocks apart, and at least one of them will be
:nonfunctional, as it no longer has a carburetor system to send fuel and
:air to its cylinders, will have its timing way off due to the missing
:eight cylinders, and won't posses a distributer to fire its spark plugs.
:

So how do you decide where 'the engine' stops?

: : : If I ta
:
: You talked a lot, but the answer is weak. Now lets take a progression
: and see how many engines we're talking about at each stage by your
: definitions:
:
: Start with a pressurized system with four chambers and four nozzles.
: Since there is no pump, presumably this is counted as four engines,
: just like the example of the solids.
:
:But again , you're talking hypothetical rocket systems - not anything
:anyone has really built due to their obvious shortcomings.
:

Of course I am. Any good taxonomy will cover everything, not just
stuff you've currently seen.

:
:You can make a good case for the original pressure-fed version of the
:four barreled XLR-11 used in the original X-1 flights as being a single
r multiple rocket engine... but what's your point? It only existed in
:the four-barreled version, and no one ever suggested making a
:two-barreled or six-barreled version of it.
:When it did get a turbopump in the later version it was a single
:turbopump feeding all four combustion chambers, and it was still
:described as a XLR-11 with the turbopump simply replacing the pressure
:feed system.
:

So to your mind it suddenly (perhaps) transmogrifies from multiple
engines when pressure fed to being a single engine when fed by
turbopump. So IDENTICALLY THE SAME HARDWARE changes from a multiple
engines to a single engine or back depending solely on what is used to
pressurize the propellants?

That just doesn't seem to make sense, Pat.

:
:
: Now add a single set of turbopumps with no other changes. Now,
: according to you, the original four engines are magically transformed
: into one engine.
:
:
:That would be exactly the case, as none of the engine's individual
:combustion chambers can work on its own without that turbopump feeding
:it fuel and oxidizer.
:

Again, multiple engines suddenly transmogrify into a single engine
based solely on how the propellant is pressurized.

Again, that just doesn't seem to make sense.

: Now add three more sets of turbopumps. It's suddenly four engines
: again.
:
: What happens if instead of adding a pump for propellant and oxidizer,
: we only add propellant pumps and leave the oxidizer pressure-fed? Now
: what is it?
:
:
:Again, what you are doing is creating philosophical concepts, not real
:hardware that has ever been built - to try to create some sort of
:razor's edge description of what a thing is via sophistry.
:

No, I'm just trying to point out where your taxonomic system breaks
down. And it *does* break down.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn