SA-214, the Last Cluster Booster

I've posted a rarely seen photo of the last Saturn IB booster stage,
built for
the SA-214 vehicle, at the following address.

"http://geocities.com/launchreport/sa214.html"

Today, with the agency scrambling to develop a new Saturn IB class
Crew Launch Vehicle, it almost hurts to view this photograph of one of
three powerful booster stages that NASA saw fit, in another time, to
scrap.

- Ed Kyle

Ed Kyle wrote:

I've posted a rarely seen photo of the last Saturn IB booster stage,
built for
the SA-214 vehicle, at the following address.

"http://geocities.com/launchreport/sa214.html"

Today, with the agency scrambling to develop a new Saturn IB class
Crew Launch Vehicle, it almost hurts to view this photograph of one of
three powerful booster stages that NASA saw fit, in another time, to
scrap.



Yeah, but it was pretty large and heavy for its capabilities, and eight
motors is about where you start to worry about the odds of a
catastrophic single engine failure occurring and destroying the stage.
Mind you, it beats the hell out of putting thirty engines in the first
stage like the N-1 did.
That was just asking for it. :-D

Pat

Pat Flannery wrote:
Ed Kyle wrote:

I've posted a rarely seen photo of the last Saturn IB booster stage,
built for
the SA-214 vehicle, at the following address.

"http://geocities.com/launchreport/sa214.html"

Today, with the agency scrambling to develop a new Saturn IB class
Crew Launch Vehicle, it almost hurts to view this photograph of one of
three powerful booster stages that NASA saw fit, in another time, to
scrap.



Yeah, but it was pretty large and heavy for its capabilities, and eight
motors is about where you start to worry about the odds of a
catastrophic single engine failure occurring and destroying the stage.

The S-IB stage wasn't as heavy as it looked. It actually compares
well with the Zenit 3 first stage - which can be considered a modern
equivalent in that it uses the same propellants and delivers about the
same total impulse. S-IB had a propellent mass ratio of about 0.907.
The Zenit first stage propellent ratio is about 0.909.

And although it is not a fair comparison (because different propellents

are used), it is still interesting to note that SRB and Delta 4 CBC are

both "heavier", relatively speaking, than S-IB. SRB has a 0.846
propellant mass ratio, Delta 4 CBC has a 0.882 ratio.

As for the probability of catastrophic engine failure, it would be
interesting to compare the probability of a CATO in an H-1 cluster
with the probability of a CATO in an SRB.

- Ed Kyle

In article ,
Pat Flannery wrote:
Yeah, but it was pretty large and heavy for its capabilities...

The S-IB was eight tons lighter than the S-I, due to a combination of
reduced requirements(*) and better understanding of margins. Despite
MSFC's reputation for conservative engineering, my recollection is that
the numbers actually don't come out all that badly.

(* The original S-I's design payloads included Dyna-Soar and RIFT (flight
test of a nuclear engine), and the demise of those payloads reduced both
maximum bending loads and maximum axial loads. )

...and eight
motors is about where you start to worry about the odds of a
catastrophic single engine failure occurring and destroying the stage.

Not seriously. Such things are quite rare in well-developed hardware.
One of the Saturn Is had a turbopump strip its gears, and the engine just
quietly shut down. (The gear design was already understood to be marginal
and fixes were already in the works.)

Mind you, it beats the hell out of putting thirty engines in the first
stage like the N-1 did.
That was just asking for it. :-D

What was asking for it on the N1, much more than the engine count, was the
lack of full-scale ground testing of the first stage.
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |

Ed Kyle wrote:

The S-IB stage wasn't as heavy as it looked. It actually compares
well with the Zenit 3 first stage - which can be considered a modern
equivalent in that it uses the same propellants and delivers about the
same total impulse. S-IB had a propellent mass ratio of about 0.907.
The Zenit first stage propellent ratio is about 0.909.


Yeah, but look at the actual physical size of the two stages:
S-1B was 6.52 m. in diameter by 24.48 m. long, and weighed in at 448,648
kg. fully fueled.
Zenit's first stage is 3.90 m. in diameter by 32.90 m. long and weighs
in at 354,300 kg. fully fueled.
Although using the Jupiter and Redstone tankage tooling made for a quick
way to make a large rocket stage (the S-1B stage consisted of a large
diameter central LOX tank based on the Jupiter tooling, surrounded by a
total of eight smaller diameter tanks based on the Redstone tooling,
four of which held LOX and four kerosene) without much new tooling
needed, it wasn't a very efficient design from an internal volume vs.
overall size viewpoint due to the empty spaces between the clustered tanks.
For a really clunky design, compare the R-7 Semyorka to Atlas for size
and weight.
Both the stage and a half Atlas D (such as used to launch Mercury) and
central core and four strap-ons R-7-8A91 (such as used for Sputnik 3)
could carry about the same payload into orbit. Atlas D weighed in at
120,000 kg. fully fueled and the R-7-8A91 at 269,973 kg. fully fueled.
Hoorah for balloon tankage.

And although it is not a fair comparison (because different propellents

are used), it is still interesting to note that SRB and Delta 4 CBC are

both "heavier", relatively speaking, than S-IB. SRB has a 0.846
propellant mass ratio, Delta 4 CBC has a 0.882 ratio.



That is to be expected given the lower isp of the SRB's fuel as well as
its need for a heavy pressure resistant casing and the low density of
the LH2 used in the Delta 4 with its need for large insulated tankage.

As for the probability of catastrophic engine failure, it would be
interesting to compare the probability of a CATO in an H-1 cluster
with the probability of a CATO in an SRB.


Tricky to do...we probably have a fair amount of data on the reliability
of the H-1 due to so many Thor and Delta flights, but we only have the
one SRB failure on Challenger to use for the SRB reliability
figures...and the design has been improved since then.

Pat

Pat Flannery wrote:
Ed Kyle wrote:

The S-IB stage wasn't as heavy as it looked. It actually compares
well with the Zenit 3 first stage - which can be considered a modern
equivalent in that it uses the same propellants and delivers about the
same total impulse. S-IB had a propellent mass ratio of about 0.907.
The Zenit first stage propellent ratio is about 0.909.


Yeah, but look at the actual physical size of the two stages:
S-1B was 6.52 m. in diameter by 24.48 m. long, and weighed in at 448,648
kg. fully fueled.
Zenit's first stage is 3.90 m. in diameter by 32.90 m. long and weighs
in at 354,300 kg. fully fueled.

True, Zenit's first stage weighs 21-22% less, both fueled and
empty, than S-IB did, but Saturn's multi-tankage layout itself is
not necessarily the dominant reason why. One important
reason is that Zenit's RD-171 main engine is seriously more
fuel efficient than Saturn's H-1 engines. RD-171 has a
311/337 sec sea-level/vacuum specific impulse, 14-19% better
than H-1's 262/296 sec. ISP. Another reason is that Saturn IB
was designed to haul more payload. A Saturn IB could put
15.6 tonnes into a 50 degree 200 km orbit, about 14% more
than Zenit.

As I recall - but don't trust me on this completely - the cluster
tankage only added something like 10% to the S-IB dry mass
versus an ideal single diameter tank design. Of course,
first stage dry mass is quite a bit less important than upper
stage dry mass for total vehicle performance.

As for size, S-IB was shorter and fatter than Zenit, which isn't
much of a big deal. The Saturn stage could be hauled on a
relatively simple trailer pulled by a standard cab-over semi-tractor.
Zenit uses a slick erector system. NASA never bothered to
develop such a setup - Saturns were erected with a gantry bridge
crane augmented by a mobile ground crane - but there is no
reason that a Saturn erector could not have been developed if
needed.

It is interesting, BTW, to note that RD-171 weighs 8.8 tonnes
dry while Saturn's eight H-1 engines taken together only
weighed about 7.2 tonnes.

Although using the Jupiter and Redstone tankage tooling made for a
quick
way to make a large rocket stage (the S-1B stage consisted of a large
diameter central LOX tank based on the Jupiter tooling, surrounded by a
total of eight smaller diameter tanks based on the Redstone tooling,
four of which held LOX and four kerosene) without much new tooling
needed, it wasn't a very efficient design from an internal volume vs.
overall size viewpoint due to the empty spaces between the clustered tanks.
For a really clunky design, compare the R-7 Semyorka to Atlas for size
and weight.
Both the stage and a half Atlas D (such as used to launch Mercury) and
central core and four strap-ons R-7-8A91 (such as used for Sputnik 3)
could carry about the same payload into orbit. Atlas D weighed in at
120,000 kg. fully fueled and the R-7-8A91 at 269,973 kg. fully fueled.
Hoorah for balloon tankage.

R-7 may not have matched the Atlas mass ratio, but it is hard to argue
with its results. R-7 (still the world's busiest launcher) has now
flown
about 1,150 more times than the stage-and-a-half Atlas (retired in
2004)
did!

- Ed Kyle

Ed Kyle wrote:

R-7 may not have matched the Atlas mass ratio, but it is hard to argue
with its results. R-7 (still the world's busiest launcher) has now
flown
about 1,150 more times than the stage-and-a-half Atlas (retired in
2004)
did!



Yeah, it was a resounding success...but jeeze, those engines are about
1/2 step forward from a V-2's.

Pat

Pat Flannery wrote:
Ed Kyle wrote:

R-7 may not have matched the Atlas mass ratio, but it is hard to argue
with its results. R-7 (still the world's busiest launcher) has now
flown
about 1,150 more times than the stage-and-a-half Atlas (retired in
2004)
did!



Yeah, it was a resounding success...but jeeze, those engines are about
1/2 step forward from a V-2's.


Maybe that is why R-7 has been successful. There seems to be a
place for "low-tech" ruggedness. The USAF is still flying B-52s
of the same vintage as the early R-7s, after all (and could keep them
flying for decades more if needed). B-52Hs are still powered by the
same engines that pushed DC-8s and 707s around - engines that
themselves weren't far removed from the J57s that might be
considered the V-2 engines of the jet age.

Another R-7 (Soyuz-FG/Fregat) launched just a few minutes ago
with Europe's answer to GPS, BTW. That makes 1,705 R-7s and
counting!

- Ed Kyle

"Ed Kyle" wrote in news:1135750019.850307.129440
@g44g2000cwa.googlegroups.com:


Pat Flannery wrote:


Yeah, it was a resounding success...but jeeze, those engines are about
1/2 step forward from a V-2's.


Maybe that is why R-7 has been successful. There seems to be a
place for "low-tech" ruggedness. The USAF is still flying B-52s
of the same vintage as the early R-7s, after all (and could keep them
flying for decades more if needed). B-52Hs are still powered by the
same engines that pushed DC-8s and 707s around - engines that
themselves weren't far removed from the J57s that might be
considered the V-2 engines of the jet age.

Though it does appear that both are going to be re-engined
with more modern (and efficient) designs. Don't know about the
B-52s engines, but the ol' R-7's are kinda interesting and
nearly unique, being spun up with hydrogen peroxide instead
of a 'hot' gas generator. The 'staged combustion' HTP/kero
engines that the Black Knight/Arrow? used were interesting, too.
Not really high performance, but good enough in subtle ways
to do the job.

--Damon

On 27 Dec 2005 22:06:59 -0800, "Ed Kyle" wrote:

The USAF is still flying B-52s
of the same vintage as the early R-7s, after all (and could keep them
flying for decades more if needed)

....Actually, the last I heard they were looking at keeping them in
service until 2025 at least, with some extended projections going as
far as 2040 provided there's a refit program to inspect and retrofit
every single one in service conducted sometime between 2015 and 2020.
There's even been one study that claimed they could be extended for a
full century of service.

It should be noted that similar claims have not been made for the
B-1B...

OM
--
]=====================================[
] OMBlog - http://www.io.com/~o_m/omworld [
] Let's face it: Sometimes you *need* [
] an obnoxious opinion in your day! [
]=====================================[