STS-42: Puzzled by Bondar's "Columbia more powerful than Discovery"

Grabbed Roberta Bondar's "Touching the Earth" from the library.

Regarding STS-42 which hauled up Spacelab, she states that it was
originally planned as a 10-day mission with Columbia, but had been
bumped to Discovery and the mission length (but not content) cut to
seven days. This made the mission workload extremely frenetic. The
reason she gives is that "the more powerful Columbia could keep
Spacelab aloft for 10 days, but Discovery could only keep it aloft for
seven days".

(Apologies to Ms Bondar for any misquotes; I don't have the text in
front of me.)

This puzzled me, since Columbia was heavier and therefore able to lift
less. Maybe it was something to do with onboard power supplies? (As it
turns out, the mission was extended to eight days anyway; NASA says
for "continued scientific experimentation".)

There were other bits where I thought I spotted technical
inaccuracies, but this is the only one that left me puzzled.

On 06/17/2010 01:47 PM, Ed Treijs wrote:
Grabbed Roberta Bondar's "Touching the Earth" from the library.

Regarding STS-42 which hauled up Spacelab, she states that it was
originally planned as a 10-day mission with Columbia, but had been
bumped to Discovery and the mission length (but not content) cut to
seven days. This made the mission workload extremely frenetic. The
reason she gives is that "the more powerful Columbia could keep
Spacelab aloft for 10 days, but Discovery could only keep it aloft for
seven days".

(Apologies to Ms Bondar for any misquotes; I don't have the text in
front of me.)

This puzzled me, since Columbia was heavier and therefore able to lift
less. Maybe it was something to do with onboard power supplies?

More or less. The power is supplied by the fuel cells. The fuel cells
are supplied by cryogenic hydrogen and oxygen. Columbia could
accommodate an Extended Duration Orbiter (EDO) kit with extra cryo
tanks, but IIRC Discovery could not.

On Thu, 17 Jun 2010 22:02:51 -0500, "Jorge R. Frank"
wrote:

On 06/17/2010 01:47 PM, Ed Treijs wrote:
Grabbed Roberta Bondar's "Touching the Earth" from the library.

Regarding STS-42 which hauled up Spacelab, she states that it was
originally planned as a 10-day mission with Columbia, but had been
bumped to Discovery and the mission length (but not content) cut to
seven days. This made the mission workload extremely frenetic. The
reason she gives is that "the more powerful Columbia could keep
Spacelab aloft for 10 days, but Discovery could only keep it aloft for
seven days".

(Apologies to Ms Bondar for any misquotes; I don't have the text in
front of me.)

This puzzled me, since Columbia was heavier and therefore able to lift
less. Maybe it was something to do with onboard power supplies?

More or less. The power is supplied by the fuel cells. The fuel cells
are supplied by cryogenic hydrogen and oxygen. Columbia could
accommodate an Extended Duration Orbiter (EDO) kit with extra cryo
tanks, but IIRC Discovery could not.

Right. Columbia and Endeavour had the EDO capability. Discovery and
Atlantis did not. Endeavour flew with it once (STS-67) all the other
EDO flights were on Columbia.

Brian

On Jun 19, 7:45*pm, Brian Thorn wrote:
On Thu, 17 Jun 2010 22:02:51 -0500, "Jorge R. Frank"





wrote:
On 06/17/2010 01:47 PM, Ed Treijs wrote:
Grabbed Roberta Bondar's "Touching the Earth" from the library.

Regarding STS-42 which hauled up Spacelab, she states that it was
originally planned as a 10-day mission with Columbia, but had been
bumped to Discovery and the mission length (but not content) cut to
seven days. This made the mission workload extremely frenetic. The
reason she gives is that "the more powerful Columbia could keep
Spacelab aloft for 10 days, but Discovery could only keep it aloft for
seven days".

(Apologies to Ms Bondar for any misquotes; I don't have the text in
front of me.)

This puzzled me, since Columbia was heavier and therefore able to lift
less. Maybe it was something to do with onboard power supplies?

More or less. The power is supplied by the fuel cells. The fuel cells
are supplied by cryogenic hydrogen and oxygen. Columbia could
accommodate an Extended Duration Orbiter (EDO) kit with extra cryo
tanks, but IIRC Discovery could not.

Right. Columbia and Endeavour had the EDO capability. Discovery and
Atlantis did not. Endeavour flew with it once (STS-67) all the other
EDO flights were on Columbia.


That would not necessarily be an EDO flight as 10 days is rather short
for an EDO-equipped OV. For example, on STS-50, the first flight of
the EDO kit on Columbia, the duration was set at 13 days, though a
weather delay and diverting to KCS resulted in a total mission
duration of 14 days. Every other EDO flight has been 15-18 days
duration. What I think Dunbar is refering to here is that Columbia was
equipped with a fifth set of cryo tanks, which allowed for missions of
9-14 days. Later in the Shuttle program, all the other OVs were
equipped with them to allow mission durations that would support ISS
assembly and resupply.
-Mike

On Sun, 20 Jun 2010 16:54:17 -0700 (PDT), Mike DiCenso
wrote:


Right. Columbia and Endeavour had the EDO capability. Discovery and
Atlantis did not. Endeavour flew with it once (STS-67) all the other
EDO flights were on Columbia.


That would not necessarily be an EDO flight as 10 days is rather short
for an EDO-equipped OV.

STS-67 flew 16 Days, 15 Hours (March 2-18, 1995) with the EDO pallet.

Brian

On Jun 21, 4:03*pm, Brian Thorn wrote:
On Sun, 20 Jun 2010 16:54:17 -0700 (PDT), Mike DiCenso

wrote:
Right. Columbia and Endeavour had the EDO capability. Discovery and
Atlantis did not. Endeavour flew with it once (STS-67) all the other
EDO flights were on Columbia.

That would not necessarily be an EDO flight as 10 days is rather short
for an EDO-equipped OV.

STS-67 flew 16 Days, 15 Hours (March 2-18, 1995) with the EDO pallet.

I think you got a bit mixed up, Brian. I was refering to the mission
duration Bondar was speaking of in context to her referencing Columbia
could do a 10 day mission to Discovery's 7 days (which was extended to
8 days by careful conservation of resources). Columbia did not need an
EDO pallet for a 10 day mission, as it had a 5th cryo tank set
installed under the payload bay. The only orbiter to have such until
the the ISS-era necessitated their use in the other OVs.
-Mike

On Tue, 22 Jun 2010 21:16:07 -0700 (PDT), Mike DiCenso
wrote:

Right. Columbia and Endeavour had the EDO capability. Discovery and
Atlantis did not. Endeavour flew with it once (STS-67) all the other
EDO flights were on Columbia.

That would not necessarily be an EDO flight as 10 days is rather short
for an EDO-equipped OV.

STS-67 flew 16 Days, 15 Hours (March 2-18, 1995) with the EDO pallet.

I think you got a bit mixed up, Brian. I was refering to the mission
duration Bondar was speaking of in context to her referencing Columbia
could do a 10 day mission to Discovery's 7 days (which was extended to
8 days by careful conservation of resources). Columbia did not need an
EDO pallet for a 10 day mission, as it had a 5th cryo tank set
installed under the payload bay. The only orbiter to have such until
the the ISS-era necessitated their use in the other OVs.

Ah, gotcha. Looked to me like you were saying STS-67 wasn't EDO.

Brian

On Jun 17, 11:02*pm, "Jorge R. Frank" wrote:
On 06/17/2010 01:47 PM, Ed Treijs wrote:

(Apologies to Ms Bondar for any misquotes; I don't have the text in
front of me.)

.....

More or less. The power is supplied by the fuel cells. The fuel cells
are supplied by cryogenic hydrogen and oxygen. Columbia could
accommodate an Extended Duration Orbiter (EDO) kit with extra cryo
tanks, but IIRC Discovery could not.

I have the book in front of me. What the text actually says is:

"This flight was originally scheduled to be a ten-day mission. The
change in orbiters, from Columbia to Atlantis and then to Discovery,
meant that it was impossible tor NASA to put all the expteriments into
a relaxed timeline, or schedule, for the crew. Because Discovery can't
keep the heavy Spacelab aloft for as long as the more powerful
Columbia can, the ten days have been compressed into seven." (pg
45-46)

From this writing of Dr Bondar's, I picture the orbiter hanging tail-
down, with the main engines blazing (well, as blazing as hydrogen-
fuelled engines get), trying to keep the whole shebang from falling
back to earth.

Dr Bondar has a real doctorate and numerous honorary degrees, but they
aren't in aerospace engineering. And good writing is harder to do than
it looks. Yes, it's just a throwaway sentence or two in the book, but
it really suggests a number of incorrect conclusions.