Tales of the IGY

On Tue, 23 Sep 2003 20:50:21 GMT, Doug...
wrote:

In article ,
says...

snip some truly excellent stuff

Well, Andrew and Doug, you only have yourself to blame.
I should not be encouraged.

Oh, yes you should! That was wonderful.

More. Please.

....And while you're at it...Henry? How about reposting your correction
submissions?


OM

--

"No ******* ever won a war by dying for | http://www.io.com/~o_m
his country. He won it by making the other | Sergeant-At-Arms
poor dumb ******* die for his country." | Human O-Ring Society

- General George S. Patton, Jr

In article ,
OM om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org wrote:
More. Please.

...And while you're at it...Henry? How about reposting your correction
submissions?

More commentary than corrections...

In article ,
Len wrote:
...The U.S. was trying to preserve the
"research" heritage by deriving the first stage from the
Viking, rather than from a ballistic missile. The
Vanguard was a rather sophisticated vehicle for its time...

I note with interest that in his book, Kurt Stehling (Vanguard's head of
propulsion) says that if the Vanguard launcher had really *been* what it
was frequently billed as -- a slightly improved Viking plus a slightly
improved Aerobee-Hi plus a solid third stage -- it would probably have
been flying a year earlier and probably *would* have launched the first
satellite, although only a rather small one.

He thought much of Vanguard's grief came from the rather drastic revisions
made to increase the performance of both the "existing" stages (the
all-new third stage was ready on schedule and never gave the slightest
trouble), and that if the Stewart committee had really understood how much
new development was involved, it might well have chosen Jupiter C instead.

(I'm less sure. I see signs of a familiar pattern: valuing promises of
greater immediate science return over getting something flying quickly and
then improving it to increase science return. It's terribly tempting to
think that there is no need to experiment and evolve if you are smart
enough to do it right the first time. As it was, three generations of
successively-improved Explorers flew before the first instrumented
Vanguard.)

official recognition for Jupiter C--which was derived from
the Redstone and had a "tub" of, if I recall correctly,
11 solid rockets derived from the WAC Corporal by JPL,
surrounding three more of these solid rockets, and topped
off with a similar, single, final, fourth rocket stage...

Correct. The solid rockets don't seem to have had a name of their own; a
JPL paper on them described the design as "a 6-in. OD scale model of an
early version of the powerplant of the Sergeant missile", with minor
modifications, notably structural reinforcements to the second-stage
nozzles to keep them from deflecting outward under spin loads (180G at
the design spin rate).

...The modified
Redstone could reach orbital altitude, at which point the
"tub" of solid rockets was to be spun up to 700 rpm for
spin stabilization.

Small correction: the tub was already spinning at launch, although the
spin rate was actively controlled (and in fact was varied in flight, to
stay away from the first-stage body-bending vibration-mode frequencies).
I don't know why they did it that way; Vanguard's approach of spinning up
the third stage just before ignition was better, although unproven until
its flight test on Vanguard TV-1.
--
MOST launched 1015 EDT 30 June, separated 1046, | Henry Spencer
first ground-station pass 1651, all nominal! |

(Henry Spencer) wrote in message ...
In article ,
OM om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org wrote:
More. Please.

...And while you're at it...Henry? How about reposting your correction
submissions?

More commentary than corrections...

In article ,
Len wrote:
...The U.S. was trying to preserve the
"research" heritage by deriving the first stage from the
Viking, rather than from a ballistic missile. The
Vanguard was a rather sophisticated vehicle for its time...

I note with interest that in his book, Kurt Stehling (Vanguard's head of
propulsion) says that if the Vanguard launcher had really *been* what it
was frequently billed as -- a slightly improved Viking plus a slightly
improved Aerobee-Hi plus a solid third stage -- it would probably have
been flying a year earlier and probably *would* have launched the first
satellite, although only a rather small one.

He thought much of Vanguard's grief came from the rather drastic revisions
made to increase the performance of both the "existing" stages (the
all-new third stage was ready on schedule and never gave the slightest
trouble), and that if the Stewart committee had really understood how much
new development was involved, it might well have chosen Jupiter C instead.

(I'm less sure. I see signs of a familiar pattern: valuing promises of
greater immediate science return over getting something flying quickly and
then improving it to increase science return. It's terribly tempting to
think that there is no need to experiment and evolve if you are smart
enough to do it right the first time. As it was, three generations of
successively-improved Explorers flew before the first instrumented
Vanguard.)

official recognition for Jupiter C--which was derived from
the Redstone and had a "tub" of, if I recall correctly,
11 solid rockets derived from the WAC Corporal by JPL,
surrounding three more of these solid rockets, and topped
off with a similar, single, final, fourth rocket stage...

Correct. The solid rockets don't seem to have had a name of their own; a
JPL paper on them described the design as "a 6-in. OD scale model of an
early version of the powerplant of the Sergeant missile", with minor
modifications, notably structural reinforcements to the second-stage
nozzles to keep them from deflecting outward under spin loads (180G at
the design spin rate).

...The modified
Redstone could reach orbital altitude, at which point the
"tub" of solid rockets was to be spun up to 700 rpm for
spin stabilization.

Small correction: the tub was already spinning at launch, although the
spin rate was actively controlled (and in fact was varied in flight, to
stay away from the first-stage body-bending vibration-mode frequencies).
I don't know why they did it that way; Vanguard's approach of spinning up
the third stage just before ignition was better, although unproven until
its flight test on Vanguard TV-1.

Henry's comments and corrections are always most
welcome and informative. When I reposted on
sci.space.history, it gave me an opportunity to
tweak the article--and I had already made an
adjustment in light of Henry's comment on the
"spinning tub."

Best regards,
Len