Shuttle-Mir question

Dear all,
None of the shuttle visits to the Mir space station was carried out by
Columbia. Was this only a coincidence or were there technical issues
that prevented Columbia from docking with Mir?

Thanks in advance,

Rainer

Rainer Kresken wrote:
Dear all,
None of the shuttle visits to the Mir space station was carried out by
Columbia. Was this only a coincidence or were there technical issues
that prevented Columbia from docking with Mir?

Thanks in advance,

Rainer

Columbia was heavier than the other orbiters, and after fitting her with
ODS and launching to Mir's orbit, there would not have been a
significant payload. They needed her for other missions as well, such
as Hubble servicing, Chandra launch (which used the whole length of the
payload bay and would have interfered with ODS).

However, there were plans to fit Columbia with an ODS (I believe this
was supposed to happen after STS-107), and she would have flown the
remainder of flights to the ISS like the other orbiters.

Bob Martin wrote:


However, there were plans to fit Columbia with an ODS (I believe this
was supposed to happen after STS-107), and she would have flown the
remainder of flights to the ISS like the other orbiters.

Actually, Columbia got the major work done before 107 during its major
maintenance/refit period. They removed the internal airlock, making for
a more spacious middeck. And added an external airlock. For 107, they
also extended the tunnel to connect to spacehab. Its "airlock" had the
door pointing zenit (up) because ODS wasn't plugged into it, and the
normal EVA exit (aft) was not available due to the tunnel to Spacehab.

eg: the shuttles now have 2 components in the cargo bay attached to the
crew quarters: the airlock which is a T with 3 hatches: one aft to the
cargo bay, one zenith to the ODS, and one forward to the shuttle
middeck. ODS plugs into the top part of the airlock.

The external airlock does prevent cargo modules that would take the full
length of the cargo bay. And with ODS installed, the cargo has to stop
afr enough away from the aft exit of the airlock to allow crewmembers to
exit from airlock through the aft door.

John Doe wrote:
Actually, Columbia got the major work done before 107 during its major
maintenance/refit period. They removed the internal airlock, making for
a more spacious middeck. And added an external airlock.

Did they? I know ODS/external airlock scars were added, but I'm pretty
sure Columbia retained her internal airlock.

Had Columbia flown ISS-13A.1, my guess is they they would have flown her
with the internal airlock, the tunnel adaptor, Discovery's ODS, a
tunnel, and a SpaceHab single module. This is similar to Atlantis's Mir
flights, before her internal airlock was removed.

For 107, they
also extended the tunnel to connect to spacehab. Its "airlock" had the
door pointing zenit (up) because ODS wasn't plugged into it, and the
normal EVA exit (aft) was not available due to the tunnel to Spacehab.

Basically correct, but change "ODS" to "tunnel adaptor".

eg: the shuttles now have 2 components in the cargo bay attached to the
crew quarters: the airlock which is a T with 3 hatches: one aft to the
cargo bay, one zenith to the ODS, and one forward to the shuttle
middeck. ODS plugs into the top part of the airlock.

The external airlock does prevent cargo modules that would take the full
length of the cargo bay. And with ODS installed, the cargo has to stop
afr enough away from the aft exit of the airlock to allow crewmembers to
exit from airlock through the aft door.

That's correct.

--Chris

Chris Bennetts wrote:
Did they? I know ODS/external airlock scars were added, but I'm pretty
sure Columbia retained her internal airlock.

Looking back at Google messages, you appear to be correct, there were
even posts by me stating it!. They had modified the fittings to allow
the ODS to be plugged in. (mechanical and electrical).

At the time of the Mir missions, it seems similar arrangements had been made.

On 2005-08-21, Rainer Kresken wrote:
Dear all,
None of the shuttle visits to the Mir space station was carried out by
Columbia. Was this only a coincidence or were there technical issues
that prevented Columbia from docking with Mir?

In order to dock with Mir, a new docking system had to be installed.
Originally, the Orbiters had an airlock going out into the payload bay;
to dock with Mir (and later ISS) they needed one heading "up out of" the
bay. Originally this was just fitted to Atlantis, then - by the end of
the program - it had been added to Discovery and Endeavour.

If you look at http://www.spaceflightnow.com/columb...rt/rescue.html
it's possible to notice the difference between Atlantis (with the
docking system, the large block next to the cabin) and Columbia, which
simply has a small airlock on the "tunnel".

Because of the high inclination of ISS and Mir, flights to them had a
payload penalty. Because Columbia was so much heavier than the other
orbiters - a good few tonnes - it was more efficient to use these three
orbiters for ISS, and keep Columbia for missions not requiring such
tight payload constraints - thus she flew the Hubble service missions,
for example, or the few "free-flying" missions left on the manifest.
Because of this, there was no need to add the docking system.

If you look at a pre-STS-107 flight plan - for example, this -
http://groups.google.com/group/sci.s...e607f77f9cd313
you see that Columbia was in fact planned for a single ISS flight,
STS-118/ISS-13A.1. This was possible because this particular payload was
comparatively very light.

I would assume - Jorge? - that the plan was to remove the docking system
from Discovery, then being maintained, and equip Columbia with it for
this one flight. This would save the expense of building four. As far as
I know, all the "modern" orbiters are permanently equipped with one.

--
-Andrew Gray

Andrew Gray wrote in
:

I would assume - Jorge? - that the plan was to remove the docking system
from Discovery, then being maintained, and equip Columbia with it for
this one flight. This would save the expense of building four. As far as
I know, all the "modern" orbiters are permanently equipped with one.

I'm not sure what the plan was for the hardware, actually.

--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.

On 2005-08-21, Jorge R. Frank wrote:
Andrew Gray wrote in
:

I would assume - Jorge? - that the plan was to remove the docking system
from Discovery, then being maintained, and equip Columbia with it for
this one flight. This would save the expense of building four. As far as
I know, all the "modern" orbiters are permanently equipped with one.

I'm not sure what the plan was for the hardware, actually.

Hmm. I take it there is an ODS per orbiter at the moment?

--
-Andrew Gray

Andrew Gray wrote in
:

On 2005-08-21, Jorge R. Frank wrote:
Andrew Gray wrote in
:

I would assume - Jorge? - that the plan was to remove the docking
system from Discovery, then being maintained, and equip Columbia
with it for this one flight. This would save the expense of building
four. As far as I know, all the "modern" orbiters are permanently
equipped with one.

I'm not sure what the plan was for the hardware, actually.

Hmm. I take it there is an ODS per orbiter at the moment?

At the moment, yes. We have three orbiters. I'm not sure what the plan was
back when we had four.


--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.