Shrinking Orion's crew

David Spain wrote:

On the webpage, or my section of it?


Since it's what pops up on the link as is, and that link has your name
on it, I assume it's your section of it?

Nah, it's a fluke in the webpage address; it takes you to the top of the
page instead of my section of it.
Scroll down till you get to the section with my name on it.
The page is from this great website, which is a ball to go digging
around in: http://www.projectrho.com/rocket/

Pat

"David Spain" wrote in message
...
OM wrote:
On Mon, 27 Apr 2009 23:13:23 -0500, "Jorge R. Frank"
wrote:

Even if thousands of bloggers were posting internal NASA documents (all
genuine) relating to problems with Apollo (and those problems were quite
real, quite expensive to fix, and in fact some *weren't* fixed until
literally the last minute before Apollo 11) while constantly beating the
drum that The Program Is Doomed And Webb Is A Political Hack With No
Business Running A Lemonade Stand Much Less A Program Of This Magnitude?

...Yeah, but it's still something to imagine how things would have
been different if all those bloggers had concentrated on one thing and
one thing alone: the dangers of the single-gas system of the Apollo
Block I.


I doubt the bloggers would have recognized the danger at the time.


OM

I need some enlightenment here. I thought capsule pressures on Apollo
where kept at 1ATM because of a variety of engineering issues, some
having to do with weight (gas carried aloft) and others having to do
with the structural integrity of the capsule itself. In other words the
capsule could maintain its structural integrity AND be lighter if it
wasn't pressurized to 1ATM. In order to keep the pressure low, the gas
chose was pure oxygen and I thought that was never changed. What I thought
was changed were the electrical connections?

Is that correct?

Sorta. The difference was that on the ground it was a 2 gas system with N2
making up the bulk of the gas. This way a fire in theory could not spread
nearly as quickly.

Once on orbit, it was purely O2 at a much lower pressure (top of the head
about 4.2psi) where again, the fire threat wasn't considered nearly as high.

The problem with Apollo 1 was the 17+psi of pure O2 on the ground.


Dave



--
Greg Moore
Ask me about lily, an RPI based CMC.

"Pat Flannery" wrote in message
dakotatelephone...


Jeff Findley wrote:
While true, it would have been in deep trouble had von Braun not made
Saturn V bigger than originally intended. What worries me is that Ares I
has little ability to grow bigger since it's limited by its five segment
SRB first stage.

Simple! We hang little SRBs on the big SRB! :-)
(...and you can actually see them doing that, can't you?)

Of course, especially since NASA frowned on strap on solids on EELV's...
:-P

Jeff
--
"Take heart amid the deepening gloom
that your dog is finally getting enough cheese" - Deteriorata - National
Lampoon

Greg D. Moore (Strider) wrote:
Sorta. The difference was that on the ground it was a 2 gas system with
N2 making up the bulk of the gas. This way a fire in theory could not
spread nearly as quickly.

Once on orbit, it was purely O2 at a much lower pressure (top of the
head about 4.2psi) where again, the fire threat wasn't considered nearly
as high.

The problem with Apollo 1 was the 17+psi of pure O2 on the ground.


Still a little confused. Was the 2 gas system employed before or after
the Apollo 1 mishap? And if before, why was Apollo 1 using pure O2?

When the capsule was closed prior to launch was the pressure reduced and
the gas purged to O2 before launch, during ascent or upon orbit?

Dave

by the time it flies ISS will be history, ended either by a accident
or more likely the budget, so no crew swaps really matter.

but a crew of 4 would of easily been carried by a existing
expendable............

no new manned booster was necessary or desierable, other than to line
the pockets of existing shuttle contractors..........

the money wasted on the booster to no where should of been spent on a
better capsule and service module

"David Spain" wrote in message
...
Greg D. Moore (Strider) wrote:
Sorta. The difference was that on the ground it was a 2 gas system with
N2 making up the bulk of the gas. This way a fire in theory could not
spread nearly as quickly.

Once on orbit, it was purely O2 at a much lower pressure (top of the head
about 4.2psi) where again, the fire threat wasn't considered nearly as
high.

The problem with Apollo 1 was the 17+psi of pure O2 on the ground.


Still a little confused. Was the 2 gas system employed before or after
the Apollo 1 mishap? And if before, why was Apollo 1 using pure O2?

After.

Apollo 1 had pure O2 atmosphere. During the ground check the cabin was
pressurized at over 16psi (source: wikipedia, though I thought it was closer
to 17).

The idea being they wanted to simulate the pressure difference the vessel
would feel in space (i.e. about 3.4 gauge psi). So to that on the ground,
they pressurized the cabin higher than the outside atmosphere.

This soaked everything in Oxygen and made things normally not flammable
become flammable.

The reason for pure O2 was several fold. One, save weight (fewer tanks
among other things) and perceived safety. No risk of over mixing N2 and
getting nitrogen narcosis, or lowering the pressure too quickly and getting
the bends, etc.

And "it's what they did for Mercury and Gemini".

When the capsule was closed prior to launch was the pressure reduced and
the gas purged to O2 before launch, during ascent or upon orbit?

I've read during ascent.

Dave



--
Greg Moore
Ask me about lily, an RPI based CMC.

OM wrote:
On Tue, 28 Apr 2009 12:53:22 -0400, "Jeff Findley"
wrote:

Simple! We hang little SRBs on the big SRB! :-)
(...and you can actually see them doing that, can't you?)

...And we'll hang a couple hundred Estes "F" engines off of those as
well. Could you imagine the nichrome igniter array for that!

Of course, especially since NASA frowned on strap on solids on EELV's...

...What was their final reasoning for that? Were they afraid the
boosters might cross the streams?

Adds more staging events and other LOC/LOM baddies.

"Greg D. Moore (Strider)" wrote in message
...


When the capsule was closed prior to launch was the pressure reduced and
the gas purged to O2 before launch, during ascent or upon orbit?

I've read during ascent.



They let astronauts read when they're going up. Wouldn't the letters get
all blurry from the shaking?




mk5000





Jaime Escalante: What you got?
Pancho: I got a core.
Jaime Escalante: You owe me a hundred percent. And I'll see you in the
People's Court--Stand and Deliver

OM writes:

...For future reference:

Thanks OM, noted.

Dave

"OM" wrote in message
...
On Wed, 29 Apr 2009 00:11:36 -0400, David Spain
wrote:

OM writes:

...For future reference:

Thanks OM, noted.

...Glad to help. So much for the claims I'm a troll, huh?

:-/

You're not a troll. In fact, you have a very low tolerance for trolls, so
low that I think you sometimes have "false positives" from your
Troll-O-Meter. ;-)

Jeff
--
"Take heart amid the deepening gloom
that your dog is finally getting enough cheese" - Deteriorata - National
Lampoon