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Brian Gaff · Guest

If you admit that there is no such thing as fault free operation, or that
mistakes will be made, and you want to send humans around in space, a
hostile environment, I think in the end you have to accept that this sort of
unexpected job will be needed from time to time. What I hope is that all the
expertise being learned is somehow kept and documented for the future.

When is this job supposed to occur?

Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can>t hear them
Email: briang1@blueyonder.co.uk
______________________________________________________________________________________________________________

"nmp" <address@is.invalid> wrote in message
news:4866cb17$0$14360$e4fe514c@news.xs4all.nl...
[quote]Jorge R. Frank wrote:

Alan Erskine wrote:
"Jorge R. Frank" <jrfrank@ibm-pc.borg> wrote in message
news:g9GdnbqSPpfgwPvVnZ2dnUVZ_srinZ2d@giganews.com...
Alan Erskine wrote:
"Brian Gaff" <Briang1@blueyonder.co.uk> wrote in message
news:ANr9k.17278$E41.11307@text.news.virginmedia.com...
Hmm, time was that anyone fiddling with bolts that had any pyro
devices associated with them was a no no for flight crew. Are we
saying that these are definitely categorically safe to fiddle with?
No. It shows how desparate they are to fix it.
Stated another way, they consider the risk incurred by the cosmonauts
fiddling with the pyrobolts is less than the risk incurred by
performing the next Soyuz entry without inspecting the bolts.

Have the crew trained for such a thing? I wouldn>t have thought they>d
have the right tools for removal either as it>s a rather specialised
device.

The tools were brought up on the most recent Progress.

It>s almost beginning to sound like a safe and sensible operation.

"Oh it>s just one of those things..."

Let>s hope for the best.[/quote]

Brian Gaff · Guest

Well, I>d hardly think that a bolt firing was going to damage the Soyuz,
since they are designed to fire to separate the units.
I think what worried me is that you are messing with wiring which has got
to work on all the other bolts when required, so they would need some way
to avoid any damage or shorts when removing bolts.

Maybe they should remove all bar two and use duct tape for the rest. That
would burn through very fast.. Note this is a joke.

Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can>t hear them
Email: briang1@blueyonder.co.uk
______________________________________________________________________________________________________________

"Greg D. Moore (Strider)" <mooregr_deleteth1s@greenms.com> wrote in message
news:tfednVSx6d7oY_vVnZ2dnUVZ_vqdnZ2d@earthlink.com...
[quote]"Jorge R. Frank" <jrfrank@ibm-pc.borg> wrote in message
news:g9GdnbqSPpfgwPvVnZ2dnUVZ_srinZ2d@giganews.com...
Alan Erskine wrote:
"Brian Gaff" <Briang1@blueyonder.co.uk> wrote in message
news:ANr9k.17278$E41.11307@text.news.virginmedia.com...
Hmm, time was that anyone fiddling with bolts that had any pyro devices
associated with them was a no no for flight crew. Are we saying that
these are definitely categorically safe to fiddle with?

No. It shows how desparate they are to fix it.

Stated another way, they consider the risk incurred by the cosmonauts
fiddling with the pyrobolts is less than the risk incurred by performing
the next Soyuz entry without inspecting the bolts.

It does raise two interesting questions:

1) What happens if say there>s a detonation of the bolt while removing it.
Forget the danger to the cosmonaut for now. What happens if there>s
damage to the Soyuz? They>ve just mangled their ride home. Interesting
position to be in.

2) If I>m understanding the problem, Russia is saying they>ve had the same
problem on successive flights, namely a pyro NOT firing? As I recall this
is one area where the US program has a 100% safety record (at least in
manned craft).

If that>s the case, that>s a bit scary.

--
Greg Moore
SQL Server DBA Consulting Remote and Onsite available!
Email: sql (at) greenms.com
http://www.greenms.com/sqlserver.html

[/quote]

Alan Erskine · Guest

"Brian Gaff" <Briang1@blueyonder.co.uk> wrote in message
news:qdJ9k.17658$E41.12547@text.news.virginmedia.com...
[quote]Well, I>d hardly think that a bolt firing was going to damage the Soyuz,
since they are designed to fire to separate the units.
I think what worried me is that you are messing with wiring which has got
to work on all the other bolts when required, so they would need some way
to avoid any damage or shorts when removing bolts.

Maybe they should remove all bar two and use duct tape for the rest. That
would burn through very fast.. Note this is a joke.
[/quote]
I note the joke, but don>t forget that the crew are going to have to remove
the bolt; it could short-circuit and BOOM! Even if there>s no juice going
to the bolt at the time, there>s static that it>s not designed to deal with.
The suit could be ruptured at the very least.

The bold isn>t designed for removal (not in one piece, anyway). And that>s
the real problem; the bolts aren>t designed for on-orbit removal. They>re
going to have to remove the bolt wearing cumbersome gloves, in a pressure
suite.... Sure, they>ve tried it out in the big pool, but geez....

John Doe · Guest

Alan Erskine wrote:

[quote]What about the training? That>s got to be tough.
[/quote]

The crews are not monkeys. They are intelligent human beings.

If they have people on the ground try to remove a bolt, measure the
torque and have a tool that can unscrew the bolt in a pool or on a
skating rink (aka: no traction to a floor in 1G), then they should be
able to transmit instructions to the station crew.

NASA>s micro managing of EVAs with extensive training probably has more
to do with scheduling of tasks. Of you have good grasp of how long each
task takes you can have good degree of assurance that all those tasks
will be accomplished during that EVA.

Alan Erskine · Guest

"John Doe" <jdoe@doe.org> wrote in message
news:48681aff$0$4961$c3e8da3@news.astraweb.com...
[quote]Alan Erskine wrote:

What about the training? That>s got to be tough.

The crews are not monkeys. They are intelligent human beings.
[/quote]
I>ve no doubt about that. I>m just wondering if anyone>s had the nerve/guts
to do some training with _live_ bolts on the ground. As I said before,
there>s static. Don>t forget that the bolts are not designed to be exposed
to the heat and cold cycles either. The bolts are just not designed to be
removed on-orbit.

John Doe · Guest

Alan Erskine wrote:

[quote]I>ve no doubt about that. I>m just wondering if anyone>s had the nerve/guts
to do some training with _live_ bolts on the ground. As I said before,
there>s static. Don>t forget that the bolts are not designed to be exposed
to the heat and cold cycles either. The bolts are just not designed to be
removed on-orbit.
[/quote]
They can train on the ground with unexplosive bolts. This, to check the
usability of the wrench and torque/force needed to get the bolt to unscrew.

Then, they can play with explosive bolts in a controlled room where they
can subject the bolt to various electrostatic discharges to see it it
will self detonate.

They might also rig up a remotely operated wrench to loosen the bolt and
see if it causes any danger of detonation.

I assume those bolts are normally housed in some form of cocoon designed
to capture the fragments of the exploding bolt. Does removing the cocoon
expose those bolts to conditions not experienced during 6 months of stay
in orbit and raise likelyhood of detonation ? I wouldn>t think so.

Derek Lyons · Guest

"Jorge R. Frank" <jrfrank@ibm-pc.borg> wrote:

[quote]Alan Erskine wrote:
"Brian Gaff" <Briang1@blueyonder.co.uk> wrote in message
news:ANr9k.17278$E41.11307@text.news.virginmedia.com...
Hmm, time was that anyone fiddling with bolts that had any pyro devices
associated with them was a no no for flight crew. Are we saying that these
are definitely categorically safe to fiddle with?

No. It shows how desparate they are to fix it.

Stated another way, they consider the risk incurred by the cosmonauts
fiddling with the pyrobolts is less than the risk incurred by performing
the next Soyuz entry without inspecting the bolts.
[/quote]
Which sounds frightening as hell.

D.
--
Touch-twice life. Eat. Drink. Laugh.

http://derekl1963.livejournal.com/

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL

Brian Gaff · Guest

I know very little of these sort of bolts, but its certainly not beyond the
realms of design to make systems where the actual severing device is a bolt
cutter mounted on the actual craft, not in the bolt. I doubt if it were a
self sheering bolt, whether the idea would be entertained at all. Given that
its probably a guillotine or similar device, its probably fairly safe. The
thing is though, is it that the bolts do not sheer, or that the sheerer is
not man enough to sheer them?
Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can>t hear them
Email: briang1@blueyonder.co.uk
______________________________________________________________________________________________________________

"Derek Lyons" <fairwater@gmail.com> wrote in message
news:486891a1.26177546@news.supernews.com...
[quote]"Jorge R. Frank" <jrfrank@ibm-pc.borg> wrote:

Alan Erskine wrote:
"Brian Gaff" <Briang1@blueyonder.co.uk> wrote in message
news:ANr9k.17278$E41.11307@text.news.virginmedia.com...
Hmm, time was that anyone fiddling with bolts that had any pyro devices
associated with them was a no no for flight crew. Are we saying that
these
are definitely categorically safe to fiddle with?

No. It shows how desparate they are to fix it.

Stated another way, they consider the risk incurred by the cosmonauts
fiddling with the pyrobolts is less than the risk incurred by performing
the next Soyuz entry without inspecting the bolts.

Which sounds frightening as hell.

D.
--
Touch-twice life. Eat. Drink. Laugh.

http://derekl1963.livejournal.com/

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL[/quote]

John Doe · Guest

Brian Gaff wrote:
[quote]I know very little of these sort of bolts, but its certainly not beyond the
realms of design to make systems where the actual severing device is a bolt
cutter mounted on the actual craft, not in the bolt.
[/quote]
If you use deja news /google on this group, you may find old posts from
an ex-NASA employee who spoke of the explosive bolts on the SRBs and on
launch pad. They were called "frangible" bolts and the bolts really did
explode from within, with some cocoon capturing the debris.

Whether this is the same on Soyuz, I am not sure, but I would suspect it
is very similar.

Craig Fink · Guest

JD in TX wrote:

[quote]Craig Fink <WeBeGood@GMail.Com> wrote in
news:F9GdnfVrjMb6R_nVnZ2dnUVZ_hGdnZ2d@earthlink.com:

...Russian experts have told NASA that the bolts at position 5
apparently failed to fire during both previous Soyuz descents.

Very interesting. I wonder if that>s just a co-incidence or if there is
something else (wiring issue) responsible for the failure? Since neither
of the pair of bolts at that location fired, and the previous Soyuz
experienced the exact same problem with the bolts in the same location,
it would suggest that the problem isn>t with the bolts themselves, but
possibly with the command used to fire the bolts. In other words, for
some reason, the bolts did not receive the signal to fire.
[/quote]
Yeah, I agree. If the first Space Tourist flight is include, that makes
three since they upgraded the Soyuz. Wiring or something else, maybe they
are firing, but something is hanging during the separation. Or, everything
is assembled correctly, but for some reason there is low current, not
enough to fire the bolts that have the longest wires. Hard to examine parts
that didn>t work properly and are gone. Sounds like they are getting closer
to the problem.

Also, I wonder were the diagram in the article came from, a Russian media
handout, a Russian NASA presentation, or a leaked internal document... And,
if it shows accurately "position 5"

My feeling about NASA is that they tends to rely on simulation to the point
of paralysis. Really an over reliance of simulation, that provides lots of
warm fuzzy feelings (cost is unimportant). The Russian don>t, that they
tend to get the hammer out, or ignore, or pick a scape goat for their
problems (low budget). Getting the problem down to "position 5" was
probably done with simulation of the vehicle dynamics, something they may
have done for the first time on this problem. I wonder if they simulated
the first Space Tourist flight and it didn>t fit the dynamics profile, or
the didn>t look that far back.

At least NASA would have simulated they dynamics sooner and had it narrowed
down to a certain position much sooner (the first time it happened). But
that doesn>t necessarily mean they would have found the cause, example the
ET wire problem. NASA spent lots of time scratching their heads, working on
getting more data on the problem. When the eventual fix was something that
was a very "safe", "easy", "simple", "extremely low risk" change. Soldered
electrical connections is somewhat of a "no brainer" improvement that could
have been done immediately after the problem became apparent, without
knowing exactly what the problem cause was. I wonder how many crimp
electrical connections were replaced with more robust soldered connections?
Just the few that were found to be the problem?

To change or not to change, which is more dangerous?

Derek Lyons · Guest

Craig Fink <WeBeGood@GMail.Com> wrote:

[quote]At least NASA would have simulated they dynamics sooner and had it narrowed
down to a certain position much sooner (the first time it happened). But
that doesn>t necessarily mean they would have found the cause, example the
ET wire problem. NASA spent lots of time scratching their heads, working on
getting more data on the problem.
[/quote]
They spent a lot of time scratching their heads mostly because the
problem was intermittent. Anyone with actual technichal experience
knows that intermittents are stone cold bitch to troubleshoot under
the best of conditions - and filling an ET in order to attempt to
induce the fault is just about as far from the best of conditions as
one can get.

[quote]When the eventual fix was something that was a very "safe", "easy", "simple",
"extremely low risk" change. Soldered electrical connections is somewhat of a
"no brainer" improvement that could have been done immediately after the
problem became apparent, without knowing exactly what the problem cause was.
[/quote]
In the real world, when you don>t know the cause of a problem, you
don>t go changing things just because. You also don>t have 20/20
hindsight.

D.
--
Touch-twice life. Eat. Drink. Laugh.

http://derekl1963.livejournal.com/

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL

Trekker · Guest

On Mon, 30 Jun 2008 15:09:28 +0000, Derek Lyons wrote:

[quote]They spent a lot of time scratching their heads mostly because the
problem was intermittent. Anyone with actual technichal experience
knows that intermittents are stone cold bitch to troubleshoot under the
best of conditions - and filling an ET in order to attempt to induce the
fault is just about as far from the best of conditions as one can get.
[/quote]
I have to wonder how much time and effort was spent on this problem
(prior to the last time of actually finding and fixing it.)

Sure, intermittent problems are probably the most difficult to
troubleshoot but what circuitry was involved in the tank itself? Was it
just some sensors and wiring going out to the connector on the tank? If
that>s all that was involved, I think they should have found the cause
earlier. Connections would be the first thing I would check with an
intermittent problem, especially one where a great degree of temperature
changes are involved.

That>s why I don>t think a whole lot of effort was put into figuring this
issue out until it finally because more than a nuisance and started
causing flight delays. Someone finally said "Enough is enough" and
actually troubleshot the problem instead of shrugging it off.

Jorge R. Frank · Guest

Trekker wrote:
[quote]On Mon, 30 Jun 2008 15:09:28 +0000, Derek Lyons wrote:

They spent a lot of time scratching their heads mostly because the
problem was intermittent. Anyone with actual technichal experience
knows that intermittents are stone cold bitch to troubleshoot under the
best of conditions - and filling an ET in order to attempt to induce the
fault is just about as far from the best of conditions as one can get.

I have to wonder how much time and effort was spent on this problem
(prior to the last time of actually finding and fixing it.)
[/quote]
Quite a bit.

[quote]Sure, intermittent problems are probably the most difficult to
troubleshoot but what circuitry was involved in the tank itself? Was it
just some sensors and wiring going out to the connector on the tank? If
that>s all that was involved, I think they should have found the cause
earlier. Connections would be the first thing I would check with an
intermittent problem, especially one where a great degree of temperature
changes are involved.
[/quote]
The problem is that in order to induce that temperature change, you have
to put the tank through a fill/drain cycle. You get one of those "for
free" every time you launch, but for troubleshooting, you>d want to
insert instrumentation into the loop - instrumentation you most likely
can>t launch with. That means a dedicated tanking test, which is a lot
of money and puts an additional thermal cycle on the tank, which makes
the tank more vulnerable to foam shedding when you finally do launch it.

[quote]That>s why I don>t think a whole lot of effort was put into figuring this
issue out until it finally because more than a nuisance and started
causing flight delays. Someone finally said "Enough is enough" and
actually troubleshot the problem instead of shrugging it off.
[/quote]
No, it was causing flight delays as far back as STS-114 and people were
saying enough is enough back then. The problem is that there were really
two separate root causes. Last time around, they discovered a batch of
faulty sensors. Which was a real problem, but it wasn>t the *whole* problem.


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