Difficulties of Development of US LH2 Stages

Although the Centaur stage was first launched in May 1962, its first
operational launch (Surveyor I) didn't come until May 1966. Not
counting the first launch, where the Centaur never had a chance to show
its stuff because of a first-stage failure, there were 6 flights prior
to Surveyor I, of which two or three were failures (in one case, I'm
not sure whether the failure was in the Centaur stage or not).

Contrast that with the larger S-IV stage, which first flew in January
1964 and racked up two more successes before what might be called its
first operational mission, the launch of Pegasus I, in February 1965.
Although only flown 6 times in total, the S-IV never failed. At the
time of the S-IV's first flight, Centaur's record (again, ignoring the
first flight) was 1 success in 2 attempts.

Given that the S-IV project got started later and was larger and more
complex, how is it that it became operational before the Centaur?
We're there problems with the Centaur's manufacturer (Convair, or
whatever it was called then)? Was it lack of attention that from MSFC,
Centaur's original manager, that was the trouble?

Douglas's S-IVB worked well from its initial outing.

Then there's the S-II stage, which seems to have been the bottleneck in
the development of the Saturn V. Why was it so troublesome? Was it
incompetence at North American Aviation? The stage's mass structure
fraction was lower than that of the other H2 stages. Although that's
natural for a larger stage, does it indicate that the S-II design was
sailing closer to the wind? Was that a source of development problems?

The reason I ask is that I'm wondering when a Saturn C-3-class booster
might have become operational under the previously posted question
about multi-launch LOR missions.

Proponent wrote:

The reason I ask is that I'm wondering when a Saturn C-3-class booster
might have become operational under the previously posted question
about multi-launch LOR missions.

Great question, (I too would like from the wiser ones on this one),

Carl

As a side point, I supply the following link:

http://www.cardmodels.net/

Join the group, and do a search for SA-5. The model designer has done a
amazing job with the detail on this model. He is looking for input to
finish it and dev. the whole early saturn series. I think with the
input from some of you guys, (We could help give the world what the
resin guys never did).

If you have a few moments, give this guy a hand,

Carl

"Proponent" wrote in message
ups.com...

Then there's the S-II stage, which seems to have been the bottleneck in
the development of the Saturn V. Why was it so troublesome? Was it
incompetence at North American Aviation? The stage's mass structure
fraction was lower than that of the other H2 stages. Although that's
natural for a larger stage, does it indicate that the S-II design was
sailing closer to the wind? Was that a source of development problems?

The reason I ask is that I'm wondering when a Saturn C-3-class booster
might have become operational under the previously posted question
about multi-launch LOR missions.


Start with this book and reference: Stages of Saturn
Should answer most questions asked.

gb

"g. beat " w9gb@spam protected wrote in message
...
"Proponent" wrote in message
ups.com...

Then there's the S-II stage, which seems to have been the bottleneck in
the development of the Saturn V. Why was it so troublesome? Was it
incompetence at North American Aviation? The stage's mass structure
fraction was lower than that of the other H2 stages. Although that's
natural for a larger stage, does it indicate that the S-II design was
sailing closer to the wind? Was that a source of development problems?

The reason I ask is that I'm wondering when a Saturn C-3-class booster
might have become operational under the previously posted question
about multi-launch LOR missions.


Start with this book and reference: Stages of Saturn
Should answer most questions asked.

And Angle of Attack, though it's a bit melodramatic in palces.



gb

Proponent wrote:
Although the Centaur stage was first launched in May 1962, its first
operational launch (Surveyor I) didn't come until May 1966. Not
counting the first launch, where the Centaur never had a chance to show
its stuff because of a first-stage failure, there were 6 flights prior
to Surveyor I, of which two or three were failures (in one case, I'm
not sure whether the failure was in the Centaur stage or not).

Contrast that with the larger S-IV stage, which first flew in January
1964 and racked up two more successes before what might be called its
first operational mission, the launch of Pegasus I, in February 1965.
Although only flown 6 times in total, the S-IV never failed. At the
time of the S-IV's first flight, Centaur's record (again, ignoring the
first flight) was 1 success in 2 attempts.

Given that the S-IV project got started later and was larger and more
complex, how is it that it became operational before the Centaur?
We're there problems with the Centaur's manufacturer (Convair, or
whatever it was called then)? Was it lack of attention that from MSFC,
Centaur's original manager, that was the trouble?

Douglas's S-IVB worked well from its initial outing.

Then there's the S-II stage, which seems to have been the bottleneck in
the development of the Saturn V. Why was it so troublesome? Was it
incompetence at North American Aviation? The stage's mass structure
fraction was lower than that of the other H2 stages. Although that's
natural for a larger stage, does it indicate that the S-II design was
sailing closer to the wind? Was that a source of development problems?

The reason I ask is that I'm wondering when a Saturn C-3-class booster
might have become operational under the previously posted question
about multi-launch LOR missions.

I did a write up on this a while ago. You can find it at:
"http://www.geocities.com/launchreport/aclv3cb.html"

My understanding was that Centaur suffered from weak
program management, especially when it was initially
run as an underfunded joint USAF/NASA project. The
Marshall Center was never fully committed to the project
(it was busy with Saturn). Centaur didn't start to
come together until it was shifted to the Lewis Center,
but even then it suffered a troubled development effort.
The low point was probably the AC-5 disaster, which
wasn't a Centaur problem but which cost money and
time.

Still, a remarkable program. AC-2 is still up there,
circling Earth, the Surveyors still rest on the surface of
the Moon, and AC-5 remains the largest on-pad
explosion ever seen at the Cape.

- Ed Kyle

"Proponent" wrote in message
ups.com...

Given that the S-IV project got started later and was larger and more
complex, how is it that it became operational before the Centaur?
We're there problems with the Centaur's manufacturer (Convair, or
whatever it was called then)? Was it lack of attention that from MSFC,
Centaur's original manager, that was the trouble?

Douglas's S-IVB worked well from its initial outing.

Then there's the S-II stage, which seems to have been the bottleneck in
the development of the Saturn V. Why was it so troublesome? Was it
incompetence at North American Aviation? The stage's mass structure
fraction was lower than that of the other H2 stages. Although that's
natural for a larger stage, does it indicate that the S-II design was
sailing closer to the wind? Was that a source of development problems?

NASA SP-4206 Stages of Saturn (yes, its on-line, if you don't want to read
the paper copy)

Table of Contents
http://history.nasa.gov/SP-4206/contents.htm

Have fun -- you will read how the weight issue was the real bottleneck --
and the S-II stage had to solve the problem.

gb

On 6 Oct 2006 22:25:40 -0700, "Ed Kyle" wrote:

My understanding was that Centaur suffered from weak
program management, especially when it was initially
run as an underfunded joint USAF/NASA project. The
Marshall Center was never fully committed to the project
(it was busy with Saturn). Centaur didn't start to
come together until it was shifted to the Lewis Center,
but even then it suffered a troubled development effort.
The low point was probably the AC-5 disaster, which
wasn't a Centaur problem but which cost money and
time.

....Wasn't some of that funding also misdirected to that competitor
project, Vega?

OM
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OM wrote:
On 6 Oct 2006 22:25:40 -0700, "Ed Kyle" wrote:

My understanding was that Centaur suffered from weak
program management, especially when it was initially
run as an underfunded joint USAF/NASA project. The
Marshall Center was never fully committed to the project
(it was busy with Saturn). Centaur didn't start to
come together until it was shifted to the Lewis Center,
but even then it suffered a troubled development effort.
The low point was probably the AC-5 disaster, which
wasn't a Centaur problem but which cost money and
time.

...Wasn't some of that funding also misdirected to that competitor
project, Vega?

Could be, but Vega was cancelled not long after it started
when NASA discovered that DoD was developing Agena.
Agena and Centaur handled different payload classes,
but they may have competed for funding a bit. My
recollection is that the early Mariner missions were
reprogrammed from Atlas-Centaur for launch on
Atlas-Agena boosters instead, due to the Centaur
development troubles.

- Ed Kyle

In article .net,
Greg D. Moore \(Strider\) wrote:
Start with this book and reference: Stages of Saturn ...

And Angle of Attack, though it's a bit melodramatic in palces.

Yeah, you have to take "Angle of Attack" with more than a few grains of
salt, since it was clearly meant as a movie script, not as history.

Oh, and it's "Stages to Saturn", not "Stages of Saturn".
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