Why Christer and not Suni for EVA-4?

"Jim Oberg" wrote in message
...
Can somebody review again the EMU management issues
that had pre-determined that Christer and not Suni would
make this 4th EVA? I want to make clear to my clients
that Suni's not going outside today had nothing to do
with any performance issues on Saturday -- which,
there weren't any.

Jim,

IIRC Christer and Beamer actually trained for a few array contingencies. I
can't remember if I heard it from the NASA TV PAO or read it on the CBS
website.

Jason Ciastko

Craig Fink writes:

I wouldn't call one astronauts tether the last line of redundancy. The
other astronaut could always jump out and grab the one who's tether
broke.

I think you underestimate the complexity of doing such a stunt. Being
able to aim, jump and grab the other in time is in no way easy. Note
that as soon as you let go the handrail you're unable to change
direction, rate of rotation or anything else. You will most probably
either miss him or just bump against him, even if your tether is long
enough to actually reach him.

But, a very gentle push to traverse 10-15 feet in 30 seconds wouldn't have
much force or tension when the end of the tether is reached. Mountain
climbers often rely on one rope with gravity as the force, not
microgravity.

Yeah, and they're dying often enough by doing that. Spaceflight is
dangerous enough already as it is.

I certainly wouldn't want to be the guy that orders an astronaut to "not"
jump out and save a fellow astronaut who's equipment failed (broken
tether). I think that qualifies as something more important.

Well, you don't want to be the guy and you aren't. Says a lot, too ;-)


Jochem

--
"A designer knows he has arrived at perfection not when there is no
longer anything to add, but when there is no longer anything to take away."
- Antoine de Saint-Exupery

They have the SAFER jet packs, don't forget.


"Jochem Huhmann" wrote

Jumping out for 10 feet means you have to *rely* on the tether to come
back and that tether is already your last line of redundancy. If it
snaps, you're doomed. And jumping like that for a cheap camera which was
able to drift away only because its tether *did* break would be really
silly.

He has his tether as a 1-D control, well until it breaks anyway.
Astronauts have no trouble bouncing around inside the Space Station. It's
pretty much the same as bouncing around the inside, except for the overly
bulky stiff suit. That's why practicing real world (space) would be good,
it's not the same as in the Space Station, or the Swimming Pool. Something
that might take a little bit of practice to get it right.

Seriously, would it really matter if the astronaut botched a camera
retrieval? But, an astronaut retrieval might be a different matter.

I don't think astronauts have died very often during space walks, yet. NAP.

I agree, the guy must be feeling pretty "silly" right about now, having
lost such an expensive camera. I hope they don't send him a bill for the
camera.

Safer practices and training in microgravity/vacuum might also be a good
thing. Things that just can't quite be simulated inside a ...

--
Craig Fink
Courtesy E-Mail Welcome @
--

On Mon, 18 Dec 2006 23:49:03+0100, Jochem Huhmann wrote:

Craig Fink writes:

I wouldn't call one astronauts tether the last line of redundancy. The
other astronaut could always jump out and grab the one who's tether
broke.

I think you underestimate the complexity of doing such a stunt. Being
able to aim, jump and grab the other in time is in no way easy. Note
that as soon as you let go the handrail you're unable to change
direction, rate of rotation or anything else. You will most probably
either miss him or just bump against him, even if your tether is long
enough to actually reach him.

But, a very gentle push to traverse 10-15 feet in 30 seconds wouldn't have
much force or tension when the end of the tether is reached. Mountain
climbers often rely on one rope with gravity as the force, not
microgravity.

Yeah, and they're dying often enough by doing that. Spaceflight is
dangerous enough already as it is.

I certainly wouldn't want to be the guy that orders an astronaut to "not"
jump out and save a fellow astronaut who's equipment failed (broken
tether). I think that qualifies as something more important.

Well, you don't want to be the guy and you aren't. Says a lot, too ;-)


Jochem

I didn't forget, that's why practicing in the USA suits would be better
than the Russian suits.

--
Craig Fink
Courtesy E-Mail Welcome @
--

On Mon, 18 Dec 2006 23:02:20+0000, Jim Oberg wrote:

They have the SAFER jet packs, don't forget.


"Jochem Huhmann" wrote

Jumping out for 10 feet means you have to *rely* on the tether to come
back and that tether is already your last line of redundancy. If it
snaps, you're doomed. And jumping like that for a cheap camera which was
able to drift away only because its tether *did* break would be really
silly.

"Jim Oberg" wrote in
:

Can somebody review again the EMU management issues
that had pre-determined that Christer and not Suni would
make this 4th EVA? I want to make clear to my clients
that Suni's not going outside today had nothing to do
with any performance issues on Saturday -- which,
there weren't any.


I would have thought Suni since she'd been to the array already, but maybe
the crew talked it over and she didn't want to go again.

burt

On Tue, 19 Dec 2006 00:20:50 GMT, burt wrote:

"Jim Oberg" wrote in
:

Can somebody review again the EMU management issues
that had pre-determined that Christer and not Suni would
make this 4th EVA? I want to make clear to my clients
that Suni's not going outside today had nothing to do
with any performance issues on Saturday -- which,
there weren't any.


I would have thought Suni since she'd been to the array already, but maybe
the crew talked it over and she didn't want to go again.

burt

The decision to have Fuglesang out there was made prior to the 3rd
EVA. Per Spaceflightnow.com (12/15/06):

"...a solar array repair job would be carried out by Curbeam and
Christer Fuglesang, who trained for solar array contingencies before
launch."

http://spaceflightnow.com/shuttle/st...re/index4.html

"Craig Fink" wrote in message
news
On Mon, 18 Dec 2006 15:33:20 +0000, Jim Oberg wrote:

... EMU management issues
that had pre-determined that Christer and not Suni would
make this 4th EVA? I want to make clear to my clients
that Suni's not going outside today had nothing to do
with any performance issues on Saturday -- which,
there weren't any.

Who Lost the Camera? Looks like NASA is going to be going a bit Overboard
to make sure it doesn't happen again. Glued, Screwed and tethered. After
making such a big deal about a tiny light weight golf ball, NASA must be
much more worried about a much heavier camera with almost zero initial
delta V and most likely has a lower drag coefficient than the Space
Station.


Does anyone know if the ground radars have a track on the camera?

Danny Deger

How long would it take to "start" the Soyuz or the shuttle? My guess is too
long

Danny Deger

"Jason A. Ciastko" wrote in message
...

snip

IIRC Christer and Beamer actually trained for a few array contingencies. I
can't remember if I heard it from the NASA TV PAO or read it on the CBS
website.

Jason Ciastko

If training is anything like it was in 1995 when I left it, I am sure they
did LOTS of contingency training.

Danny Deger