Jim O exclusive facts/analysis of spacewalk

John Doe wrote in :

Also, remember that they are not spending a whole afternoon in bright
sunshine, they alternate every 45 minutes between very hot and very
cold.

Common misconception. Due to ISS' altitude, it does not spend half the
orbit in shadow. Its orbit has a period of 92 minutes, and the most shadow
you can get is a 56:36 day:night split. Due to the changing declination of
the sun through the seasons, and the regression of the line of nodes of
ISS' orbit, the day:night split constantly changes. There are brief periods
(a few days each year) where the split is 92:0 (i.e. all daylight, no
shadow).


--
JRF

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

I agree, and would like to expand on your comment.

One thing that needs to be remembered about flight rules, there is a
process in place to waive them in real time. This process was put in
place (40 years ago) in recognition of the fact that when things
happen "for real", sometimes situations develop which may be outside
of what the rule's authors were thinking of when the rule was written.
Flight rules usually contain written rationale to provide the "why"
of the rule, so that they can be interpreted by the flight team
properly if an ambiguous (or possibly dangerous) situation arises
which threatens safety (first) and mission success (second).

In the case of the this rule, the rationale for two laptops being
available was so that the crew (isolated to the Russian segment for
multiple days in preparation for the EVA) would be able to view (and
respond to) the text of caution and warning messages annunciated by
the US segment, which they physically could not go to. As was pointed
out, by the time the laptops were inadvertently powered off, the crew
was already very close to going out the door, meaning that the
messages (which they could obviously not view or respond to outside)
not being available did not increase the risk of the EVA itself beyond
what it already was. It already was accepted that the ground could
adequately monitor and respond during that timeframe. Ergo, the
reason the rule existed no longer applied.

In reality, how the rule was waived provides evidence of how carefully
it is done these days. There are, in fact, rules on how to waive
other rules. During execution, the rules state the flight director
has complete (although very carefully wielded) authority to waive a
rule for safety or mission success until a consultation with the MMT
is possible. With a crew about to head out the door, the decision to
waive falls squarely within the authority of the flight director (and
his/her team, which wrote the rule in the first place) because a full
MMT meeting cannot normally be convened or briefed to a level to come
to a conclusion in that timeframe. In this case, however, they did go
above and beyond and briefed several MMT members (obviously in the
control center).

The decision to waive the rule was made to achieve mission success
(the EVA activities) which is allowable since safety was not
compromised. The rule would never have been waived if there was a
safety issue.

One thing that needs to be remembered about flight rules,

Space is a dangerous environment, indeed the equipment they use is
dangerous if not properly setup. So when you are performing an
activity and something happens you need to evaluate the risk of not
only the unexpected event but the risk that was taken to get to that
point of the mission.

So was the risk of having the backup laptop down for the EVA was
higher than the risk taken by suiting up and getting prepared for EVA.

If the laptop were for the crew to respond to station events while in
the station then it seems pretty irrelevent whether the backup was up
or down during the EVA.

Also unlike the two shuttle disasters it seems to me that this is a
straight forward assessment. They have done dozens of EVA
preparations, and they know what they need to monitor and report
stations functions. With Challenger it was the assumption about cold
weather when they never really tested for that condition, with
Columbia it was the assumption about foam striking the underside when
again they never tested that situation.

The only questionable thing I see was trying to push the envelope on
suit lifetime when they were performing the first 'empty' station EVA
on the ISS. That something more akin to the shuttle disaster than
leaving with one of the laptops down.

Rob Conley

Don't ask ME why NASA put "two" laptops on the required equipment list.
They did -- if YOU think they were wrong to do so, hassle THEM.

As to suit malfunctions -- something going wrong on a suit during a
spacewalk is ALWAYS potentially life-threatening. All you see is symptoms --
not causes.

You seem to assume that since LATER the cause appeared to be benign, then
BEFORE KNOWING THAT, a nonchalent reaction was prudent enough.

Thanks for this and your earlier history of excellent postings, by the way.
At some point i'd be interested in finding out who you really are.

I note you seem to have dropped using fake British spelling to throw off
speculations on your identity grin?

One clue: the module is called 'Pirs', which means 'pier' in Russian. You
spelled it 'Piers', the first name of a NASA astronaut.


Jim




"John Doe" wrote in message ...
JimO wrote:
My new msnbc analysis at http://msnbc.msn.com/id/4424650
and also see Friday's 'Daily Planet' (www.discovery.ca) show for
video of my interview on the walk.

I realise that you need to add sensationalism to any stories published on
a
media outlet such as Microsoft's MSNBC.

However, does the requirement to have 2 "user interface" laptops
operational
really necessary when you have 0 crewmembers in the station and much of
the
systems had been shutdown ? What would those laptops have been able to
perform
with nobody inside to pointy-click the menus ?

Secondly, were lives endangered because of the glitch in the suit ? Media
seem to want to turn this into a dramatic event (you did use the word
"dramatic" in your MSNBC article, didn't you ?)

Lets say that the russians did notice lower than normal cooling
performance
from the start, if they monitored it carefully and stopped the EVA as soon
as
it became unconfortable,.is there really anything wrong with this ?

The EVA was more akin to shovling snow in your driveway during a snowstorm
rather than walking across antarctica.

Seriously, in case of emergency, how long would it take for the crewmember
to
"run" back to the Piers airlock from anywhere in the SM ?

"John Doe" wrote in message ...
Those laptops are not watchdogs. They are glorified dumb terminals that
display stuff and allow commands to be entered.

what do you suppose NASA knew about them, that you don't?

I appreciate the insider insight here -- but I still can't reconcile it with
the following excerpt from the Feb 28 On-Orbit Status report:

"When SM panel power was turned off during EVA preps, the PCS (portable
computer system) laptop in the SM was also deactivated, which was in
violation of a flight rule and the EVA-9 Minimum Equipment List. [The
flight rule requires a minimum of two active PCS's attached to core data
busses for Caution & Warning support. After coordinated
evaluation/assessment of the situation by MCC-H specialists, including the
IMMT Chair, the violation was deemed acceptable, and EVA ops continued as
planned. The PCS was successfully reactivated following the spacewalk.] "

YOU argue that "the purpose of the PCS rule is to provide the IVA crew a way
to list C&W events and react to them", and suggest the rule is a holdover
from 3-crewmember ops when there is one IVA crewman for EVA -- but if so, my
simple question is: WHY were these laptops then STILL on the EVA-9 MINIMUM
EQUIPMENT LIST?

EVA-9 was KNOWN to be a no-IVA-crew activity, nicht wahr?

You can call/fax me additional info at 281-337-2838 here in Houston.

"a user" wrote in message
...
The purpose of the PCS rule is to provide the IVA crew a way to list C&W
events and react to them. Since they were on an EVA, the status of the
laptop in the SM was not truly critical to the crew. Ground Telemetry
can still see all C&W events and be able to react to them even if all
PCS computers were offline. Also, The Audio system still annunciates C&W
events even if all PCS's are offline. IMO the flight rule should say "an
IVA crew must have 2 active PCS's...", to an EVA crew its irrelevant. I
agree the ground made a procedure call mistake in turning off the power
feeding the SM PCS, but its an easy one to make, since the Russian power
distribution is not as well understood on the US side and the crew does
not always plug in the PCS laptops to the ports the ground thinks they
are using.

These are GREAT discussions, i am learning a lot from them, and i deeply
appreciate the efforts put into them by obviously well-informed
contributors.

jim o

The best answer to the WHY that I can come up with, is so the ISS is in
a valid IVA state (2 PCSs active) from the moment the crew opens the
airlock (PIRS) and reenters the station as IVA crew.
I guess I was implying the rule is a holdover from 3 man ops, or rather
the assumption in nearly all flight rules that the ISS is always manned.
Regardless of the flight rule and the EVA Eq. list, fact is the PCS
being unpowered would not prevent the ground from seeing all C&W events
and reacting, and they were the only people that could have seen and
reacted to C&W events during the EVA anyway.
I'm wondering when they noticed the PCS wasn't active. Was it ground or
crew? The ground must not have seen the RT disconnected from the bus
until well into the suiting up or even into depress, or else they would
have had the crew put the laptop on the correct port (that had power).
Those old 760XD batteries rarely last more than 30 minutes without
external power, so maybe the bus disconnect did not occur until the PCS
battery died (say 30 minutes after the power was turned off)

JimO wrote:
I appreciate the insider insight here -- but I still can't reconcile it with
the following excerpt from the Feb 28 On-Orbit Status report:

"When SM panel power was turned off during EVA preps, the PCS (portable
computer system) laptop in the SM was also deactivated, which was in
violation of a flight rule and the EVA-9 Minimum Equipment List. [The
flight rule requires a minimum of two active PCS's attached to core data
busses for Caution & Warning support. After coordinated
evaluation/assessment of the situation by MCC-H specialists, including the
IMMT Chair, the violation was deemed acceptable, and EVA ops continued as
planned. The PCS was successfully reactivated following the spacewalk.] "

YOU argue that "the purpose of the PCS rule is to provide the IVA crew a way
to list C&W events and react to them", and suggest the rule is a holdover
from 3-crewmember ops when there is one IVA crewman for EVA -- but if so, my
simple question is: WHY were these laptops then STILL on the EVA-9 MINIMUM
EQUIPMENT LIST?

EVA-9 was KNOWN to be a no-IVA-crew activity, nicht wahr?

You can call/fax me additional info at 281-337-2838 here in Houston.

"JimO" wrote in message ...
My new msnbc analysis at http://msnbc.msn.com/id/4424650
and also see Friday's 'Daily Planet' (www.discovery.ca) show for
video of my interview on the walk.

It seems to me that the Orlan equivalent of Caution & Warning
parameters should have been available by engineers in Houston for both
spacewalkers. If this is not so, then Houston would have to rely on
communication from Russia for indications of problems. Otherwise,
they would have been able to independently monitor cooling status.
[But I forget whether the Orlan transmits this info once the umbilical
is disconnected]

Also, at least during training on the ground (in Houston), Russians
are notorious for poopooing any problem. If cooling goes away, well
who needs cooling? Not that this happened here, but it might have.
How could the crewmember not know if he's not receiving proper
cooling? Once it starts raining in your suit is a little late to be
saying you have a problem. But, manly men will do menly things.

-Cache!

I think you are helping me close in on an understanding of this, and I'll
compose a correction to the msnbc.com piece shortly to put the issue in
better perspective.

BTW: I was the Ascent Flight Rules panel secretary for STS-1, for Neil
Hutchison, so i've been immersed in the culture for a quarter of a century
or so. I sat on console for the Silver Team that first launched a shuttle --
puckered so damned tight I was constipated for a week afterwards.

It seems to me that the dual-PCS requirement would be justified, purely on
crew annunciation grounds, in the scenario where the crew must return to
Russian segment because of a real C&W alarm -- and they then need to have
stand-alone ability to assess the alarm ASAP. They can tolerate one
addiitonal failure -- FOFuS -- of ONE of the laptops, but requiring TWO
means they will have at least one way to get this time-critical information
and act on it productively.

Am I gathering clues? I always can use more grin.

jimo





"a user" wrote in message
...
The best answer to the WHY that I can come up with, is so the ISS is in
a valid IVA state (2 PCSs active) from the moment the crew opens the
airlock (PIRS) and reenters the station as IVA crew.
I guess I was implying the rule is a holdover from 3 man ops, or rather
the assumption in nearly all flight rules that the ISS is always manned.
Regardless of the flight rule and the EVA Eq. list, fact is the PCS
being unpowered would not prevent the ground from seeing all C&W events
and reacting, and they were the only people that could have seen and
reacted to C&W events during the EVA anyway.
I'm wondering when they noticed the PCS wasn't active. Was it ground or
crew? The ground must not have seen the RT disconnected from the bus
until well into the suiting up or even into depress, or else they would
have had the crew put the laptop on the correct port (that had power).
Those old 760XD batteries rarely last more than 30 minutes without
external power, so maybe the bus disconnect did not occur until the PCS
battery died (say 30 minutes after the power was turned off)

JimO wrote:
I appreciate the insider insight here -- but I still can't reconcile it
with
the following excerpt from the Feb 28 On-Orbit Status report:

"When SM panel power was turned off during EVA preps, the PCS (portable
computer system) laptop in the SM was also deactivated, which was in
violation of a flight rule and the EVA-9 Minimum Equipment List. [The
flight rule requires a minimum of two active PCS's attached to core data
busses for Caution & Warning support. After coordinated
evaluation/assessment of the situation by MCC-H specialists, including
the
IMMT Chair, the violation was deemed acceptable, and EVA ops continued
as
planned. The PCS was successfully reactivated following the spacewalk.]
"

YOU argue that "the purpose of the PCS rule is to provide the IVA crew a
way
to list C&W events and react to them", and suggest the rule is a
holdover
from 3-crewmember ops when there is one IVA crewman for EVA -- but if
so, my
simple question is: WHY were these laptops then STILL on the EVA-9
MINIMUM
EQUIPMENT LIST?

EVA-9 was KNOWN to be a no-IVA-crew activity, nicht wahr?

You can call/fax me additional info at 281-337-2838 here in Houston.