No Shuttle 'Till 2005?

It turns out that one CAIB recommendation is adding schedule
pressure to STS. Florida Today reported at:

"http://www.floridatoday.com/columbia/columbiastory2A13038A.htm"

that the new launch criteria will limit launching to four periods
during 2004: "roughly March 11 to April 6; May 19 to June 28;
July 18 to Aug. 26 and about a three-week period between
mid-September and mid-October". There are also two three-day
periods in November 2004 and January 2005, but if NASA can't get
shuttle ready to fly by October (it has already given up on the
first one or two 2004 periods), then it probably won't be able
to launch until February 2005, according to the report.

- Ed Kyle

In article ,
ed kyle wrote:
It turns out that one CAIB recommendation is adding schedule
pressure to STS. Florida Today reported at:

"http://www.floridatoday.com/columbia/columbiastory2A13038A.htm"

that the new launch criteria will limit launching to four periods
during 2004: "roughly March 11 to April 6; May 19 to June 28;
July 18 to Aug. 26 and about a three-week period between
mid-September and mid-October". There are also two three-day
periods in November 2004 and January 2005, but if NASA can't get
shuttle ready to fly by October (it has already given up on the
first one or two 2004 periods), then it probably won't be able
to launch until February 2005, according to the report.

Okay, this is probably a really dumb question; but how easy would
it be to change the orbit of the ISS to put it in something that
is more convenient to reach from the Cape? Forget the politics, etc.,
just the mechanics?

Nick

In article ,
(Nicholas Fitzpatrick) wrote:

In article ,
ed kyle wrote:
It turns out that one CAIB recommendation is adding schedule
pressure to STS. Florida Today reported at:

"http://www.floridatoday.com/columbia/columbiastory2A13038A.htm"

that the new launch criteria will limit launching to four periods
during 2004: "roughly March 11 to April 6; May 19 to June 28;
July 18 to Aug. 26 and about a three-week period between
mid-September and mid-October". There are also two three-day
periods in November 2004 and January 2005, but if NASA can't get
shuttle ready to fly by October (it has already given up on the
first one or two 2004 periods), then it probably won't be able
to launch until February 2005, according to the report.

Okay, this is probably a really dumb question; but how easy would
it be to change the orbit of the ISS to put it in something that
is more convenient to reach from the Cape? Forget the politics, etc.,
just the mechanics?

Nick

I'll leave it to the orbital mechanics gurus to do the numbers (it's
been a long time since I calculated delta-V requirements for this type
of thing) but in general, it's REALLY hard to change planes like that,
especially for massive structures. In the case of ISS, you also have to
realize that it's fairly flimsy - lots of large structures hanging off
at odd places, like TCS radiators, solar arrays, modules hanging off the
Node(s), etc. These elements all behave like spring-mass systems and
have complicated oscillatory modes along with lateral and off-axis
stress limitations on their mechanical attachment points to the rest of
the station. That's why a simple reboost by an orbiter is a rather
complicated, drawn-out affair - you have to keep impulses from thrusting
maneuvers very low to avoid damaging the station.

Concerning real numbers, however, someone ran the figures for Columbia
to reached the ISS orbital plane from its original orbit - google for
that post and the following comments and you'll see that the this kind
of maneuver is (as Monty Python might say), "It's really, hugely,
mind-boggling hard." In terms of fuel AND the fact that the structure
is so relatively flimsy that the manuever has to happen very slowly
(small delta-Vs, spread out over a long time).

--
Herb Schaltegger, B.S., J.D.
Reformed Aerospace Engineer
"Heisenberg might have been here."
~ Anonymous

Herb Schaltegger wrote:
[snip]

I also thought the ISS Orbital Plane was chosen specifically to benefit
the Russians and their higher latitude of launch sites.

In article , stmx3 wrote:
Herb Schaltegger wrote:
[snip]

I also thought the ISS Orbital Plane was chosen specifically to benefit
the Russians and their higher latitude of launch sites.

Yeah, but the criteria set by the original poster for this thread specified
that he wasn't interested in going into the politics, just the math (and
science) behind such a change.

-Dan

Dan Foster wrote:
In article , stmx3 wrote:

Herb Schaltegger wrote:
[snip]

I also thought the ISS Orbital Plane was chosen specifically to benefit
the Russians and their higher latitude of launch sites.


Yeah, but the criteria set by the original poster for this thread specified
that he wasn't interested in going into the politics, just the math (and
science) behind such a change.

-Dan

Ooops. Forgot.

In article ,
Dan Foster wrote:

I also thought the ISS Orbital Plane was chosen specifically to benefit
the Russians and their higher latitude of launch sites.

Yeah, but the criteria set by the original poster for this thread specified
that he wasn't interested in going into the politics, just the math (and
science) behind such a change.

Indeed I was just pondering the math. (pondering the feasibility of,
for example, someone building a special one-time use second-stage type
unit that could be used ... though given how slow an operation it would
have to be, perhaps there isn't much technology sitting on the shelf that
could burn that slow, for that long ....

Another thought though, that is raised though ... what about moving the
US launch site .... Are there more northerly launch sites that would have
better operating windows?

Nick

In article ,
Dan Foster wrote:

In article , stmx3
wrote:
Herb Schaltegger wrote:
[snip]

I also thought the ISS Orbital Plane was chosen specifically to benefit
the Russians and their higher latitude of launch sites.

Yeah, but the criteria set by the original poster for this thread specified
that he wasn't interested in going into the politics, just the math (and
science) behind such a change.

-Dan

Yeah, what Dan said!

Leaving politics aside, moving ISS to the current orbital plane was such
a technical mess . . . Since a major chunk of ISS is legacy Space
Station Freedom hardware (all the U.S. elements, the ESA Columbus
module, NASDA Kibo module, etc), it was all baselined for launch from
KSC into more or less a 28 degree orbit. Changing the plane to satisfy
Russian Baikonur constraints resulted in MAJOR shuttle payload hits;
that meant (means!) elements have to be launched stripped-down and not
fully operational, then outfitted on-orbit. That means adding flights
to launch equipment and hardware which had been baselined for
ground-based installation and checkout. That imposes increased testing
(and possibly reliability/maintainability) requirements and adds lots of
time to orbital assembly - lots more on-orbit rack-moving, connectors to
be mated and verified, etc.

Since the modules you're launching are not fully outfitted, you have
lots of new operational constraints, too. For instance, deletion of the
ECLSS ARS rack from the launch of the U.S. Lab module meant that all the
procedures established for module entry and activation had to be redone:
from verifying internal cabin atmosphere prior to hatch opening (which
was to be done with the ARS GC/mass spectrometer and MCA) to software
loads [the ARS rack had (has?) an MDM that also controlled equipment in
other racks] to power-up procedures. The list goes on and on.

All those things had to be changed for just about every system and every
procedure due to the seemingly simple change to orbital inclination.

--
Herb Schaltegger, B.S., J.D.
Reformed Aerospace Engineer
"Heisenberg might have been here."
~ Anonymous

On 18 Sep 2003 11:52:01 -0400, (Nicholas Fitzpatrick)
wrote:


Okay, this is probably a really dumb question; but how easy would
it be to change the orbit of the ISS to put it in something that
is more convenient to reach from the Cape?

Extremely difficult and time-consuming.

And the result would be a Space Station that the Russians can't reach,
which isn't exactly something wise to do this year or next. :-)

Brian

On Thu, 18 Sep 2003, Brian Thorn wrote:

On 18 Sep 2003 11:52:01 -0400, (Nicholas Fitzpatrick)
wrote:


Okay, this is probably a really dumb question; but how easy would
it be to change the orbit of the ISS to put it in something that
is more convenient to reach from the Cape?

Extremely difficult and time-consuming.

And the result would be a Space Station that the Russians can't reach,
which isn't exactly something wise to do this year or next. :-)

One of the handful of advantages the U.S. has gotten from the partnership
with the Russians. If only the Russian economy was in a little bit better
shape.
-Mike