Expedition 16 lands 260 miles and 20 minutes past target?

"John Doe" wrote in message
...
Greg D. Moore (Strider) wrote:

One can argue that the Russians don't really need to pinpoint the target

One could argue that. Just like one could argue you don't have to fix
the
O-Rings since the worst burn-thru still left 30% of the O-ring left.

There is a big difference. The o-rings are a catastrophic result.
Landing off-course doesn't because the area is not populated, flat
toundra all around so it isn't as if they were to land in the alps if
they missed a small flat area in the middle of Switzerland.



No, this is the mistake that people fall into. When you start to RELY on
your backups working, YOU HAVE MAJOR ISSUES. The O-rings were never
supposed to be impacted at all, let alone routinely in 26 flights. The
Soyuz TMA should NOT be routinely going into a ballastic re-entry mode.
Once you can maybe right off. A 33% failure rate is not something you can
ignore.

Remember, among other things, the Soyuz is to be used to return injured
astronauts. Can you imagine what happens to an already medically
compromised patient after he experiences 10g and then lands 400km from the
waiting rescue vehicles?

It's great the backup worked, it's far from great that it's a routine
occurance.

But even if NASA has all the budget to fix those glitches,

Umm, NASA's aint paying to fix these glitches.


I was refering the glitches that will happen with CEV. NASA will have
the budgets and incentives to fix them if it ops for land landings
because landing 260 miles off course would be big news in the USA. For
russia, it doesn't really make that big a deal to land offcourse because
it won't hurt anyone.

Neither did blow-by on O-rings. Until it did.



What sort of G forces are we talking about here in the case of a
ballistic re-entry vs normal re-entry ? is it 3G instead of 2 ? Is it
10Gs instead of 2 ?

10G instead of 2 or 3.





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

"Brian Thorn" wrote in message
news
On Sun, 20 Apr 2008 15:40:46 -0400, John Doe wrote:


One could argue that. Just like one could argue you don't have to fix
the
O-Rings since the worst burn-thru still left 30% of the O-ring left.

There is a big difference. The o-rings are a catastrophic result.
Landing off-course doesn't

Yet.

Since Russia clams up about the ballistic entries, we have no idea
what's really causing it, or if that problem can propogate to other
systems that _would_ cause a catastrophic result.

Exactly. We're ignoring all the other things that could go wrong because we
don't know exactly what's happening.

What happens if next time the capsule re-enters in the wrong orientation.
Or the parachutes fail due to the ballastic re-entry, etc.



Brian



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

BBC reports on this issue.

http://news.bbc.co.uk/2/hi/science/nature/7355912.stm
(It has picture of a smiling Peggy Whitson).


"severe G-forces"

420km from its planned landing point. 20 minutes later than schedule.
BBC also mentions 10-Gs experienced. Aslo confirms it was done using
backup ballistic re-entry. Some blurb about crew changing something at
last minute without informing ground control.

I am curious about the "20 minutes later".

It is my understanding that under normal circumstances, the soyuz tries
to "ride a wave" on the thin atmosphere to slow down its rate of descent
(and loose speed before it reaches dense atmosphere).

So doing a ballistic re-entry would have the spacecraft increase its
downward velocity at greater rate. This means reaching desnser
atmnosphere faster and one would conclude reaching the ground faster.
Can anyone explain the principle behind the ballistic re-entry taking
longer ?


or does the "20 minutes later" refer to the search-rescue folks arriving
20 minutes after the original plan for arrival of crews ?


I tend to agree that 10Gs is pretty severe and that this is not the
"mild inconvenience" we are led to believe. It is a shame that we don't
hear so much about the investigation.

"Craig Fink" wrote in message
m...
Translation problem, lands short

http://www.spaceflightnow.com/statio...19landing.html
...Soyuz capsule came down well short of its intended touchdown
site...

That sounds better.

Mission Control spokesman Valery Lyndin said ... touched down some
260

snip

This is interesting. Lots of attention to how the Russians got
it wrong (plus a little translation confusion) overlays the fact
*they did it* vs what are *we* doing these days? ??

Titeotwawki -- mha [2008 Apr 21 sci.space.policy]

No, I cannot get my head around this either. Surely, a steeper trajectory
equals more g, thus a shorter time, so it should have landed short?

Its obvious now why they use seat liners. No way would that g force be
acceptable otherwise I'd say.

As to crew changing landing plan... Hmm, well if you listen to comms the
Russians are always at great pains to make sure that their crew know
exactly what is supposed to be done, getting them to repeat the settings
many times as their comms are notoriously crap.


Sounds more likely that either something got knocked and was not noticed,
and the system said, that's stupid, lets do a safe re entry and ignore it.

Brian

--
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graphics are great, but the blind can't hear them
Email:
__________________________________________________ __________________________________________________ __________


"John Doe" wrote in message
...
BBC reports on this issue.

http://news.bbc.co.uk/2/hi/science/nature/7355912.stm
(It has picture of a smiling Peggy Whitson).


"severe G-forces"

420km from its planned landing point. 20 minutes later than schedule.
BBC also mentions 10-Gs experienced. Aslo confirms it was done using
backup ballistic re-entry. Some blurb about crew changing something at
last minute without informing ground control.

I am curious about the "20 minutes later".

It is my understanding that under normal circumstances, the soyuz tries
to "ride a wave" on the thin atmosphere to slow down its rate of descent
(and loose speed before it reaches dense atmosphere).

So doing a ballistic re-entry would have the spacecraft increase its
downward velocity at greater rate. This means reaching desnser
atmnosphere faster and one would conclude reaching the ground faster.
Can anyone explain the principle behind the ballistic re-entry taking
longer ?


or does the "20 minutes later" refer to the search-rescue folks arriving
20 minutes after the original plan for arrival of crews ?


I tend to agree that 10Gs is pretty severe and that this is not the
"mild inconvenience" we are led to believe. It is a shame that we don't
hear so much about the investigation.

"Greg D. Moore (Strider)" wrote in message
m...
"Craig Fink" wrote in message
m...
Mission Control spokesman Valery Lyndin said ... touched down some 260
miles
off target - a highly unusual distance given how precisely engineers plan
for such landings...the craft may have followed a so-called "ballistic
re-entry" - a very steep course which submits the crew to sometimes
severe
physical forces.
http://ukpress.google.com/article/AL...UtZAykGxQD5JMw



But just remember... capsules are safer when they fail. Who cares if they
fail more often!

At least that's what the capsule mafia will be proclaiming.

It's not a good thing that Soyuz reentry guidence keeps failing. But it is
also a good thing that it doesn't kill the people on board when it does
fail. The backup mode of doing a ballistic reentry has been "tested" far
more times than you'd think is necessary.

At this rate, the Soyuz-TM has had what 20% failure rate involving
ballastic re-entries and I believe a few other fairly major issues.

I'm sure a lot of this has to do with the Russian engineering philosophy
that says "good enough is good enough" *long* before a typical US or
European engineer would reach the same conclusion. That and the Russian
economy, and space funding, is still rather poor. It's hard to justify
upgrades to such systems when the backup seems to be working just fine.

Still, NASA lost two orbiters and crews in the process by not getting
serious enough fast enough when faced with flight anomalies. One has to
wonder if Russia is doing the same with Soyuz.

Jeff
--
A clever person solves a problem.
A wise person avoids it. -- Einstein

Jeff Findley wrote:
"Greg D. Moore (Strider)" wrote in message
m...
"Craig Fink" wrote in message
m...
Mission Control spokesman Valery Lyndin said ... touched down some 260
miles
off target - a highly unusual distance given how precisely engineers plan
for such landings...the craft may have followed a so-called "ballistic
re-entry" - a very steep course which submits the crew to sometimes
severe
physical forces.
http://ukpress.google.com/article/AL...UtZAykGxQD5JMw


But just remember... capsules are safer when they fail. Who cares if they
fail more often!

At least that's what the capsule mafia will be proclaiming.

It's not a good thing that Soyuz reentry guidence keeps failing. But it is
also a good thing that it doesn't kill the people on board when it does
fail. The backup mode of doing a ballistic reentry has been "tested" far
more times than you'd think is necessary.

It may not have been "just" a ballistic entry, either. A poster on NSF
reports (third-hand, but the original source is cited as Andre Kuipers)
that TMA-11 had a separation problem and started entry nose-forward,
similar to Soyuz 5.

*That* would be a bigger deal, if true. The Soyuz 5 problem was supposed
to have been fixed long ago.

Again, unconfirmed at this time. This should sort itself out over the
next few days.

Still, NASA lost two orbiters and crews in the process by not getting
serious enough fast enough when faced with flight anomalies. One has to
wonder if Russia is doing the same with Soyuz.

It's called "foam logic" when NASA does it; I wonder what the term would
be for Soyuz...?

John Doe wrote:

I tend to agree that 10Gs is pretty severe and that this is not the
"mild inconvenience" we are led to believe. It is a shame that we don't
hear so much about the investigation.

NASA has a history of not holding the Russian's toes to the fire, that
is when they are not actively conspiring with them to overlook and/or
hide safety problems.

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

http://derekl1963.livejournal.com/

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

On Mon, 21 Apr 2008 01:18:12 -0400, John Doe wrote:

420km from its planned landing point. 20 minutes later than schedule.
BBC also mentions 10-Gs experienced. Aslo confirms it was done using
backup ballistic re-entry. Some blurb about crew changing something at
last minute without informing ground control.

Malenchenko is now quoted as saying the problem had nothing to do with
the crew's actions.

Brian

"Jorge R. Frank" wrote in message
...
Jeff Findley wrote:

It's not a good thing that Soyuz reentry guidence keeps failing. But it
is also a good thing that it doesn't kill the people on board when it
does fail. The backup mode of doing a ballistic reentry has been
"tested" far more times than you'd think is necessary.

It may not have been "just" a ballistic entry, either. A poster on NSF
reports (third-hand, but the original source is cited as Andre Kuipers)
that TMA-11 had a separation problem and started entry nose-forward,
similar to Soyuz 5.

Now that is rather scary. Though might jive with reports the Korean
cosmonaut made regarding seeing flame outside the window. (Though I still
suspect that's the normal plasma sheath.)


*That* would be a bigger deal, if true. The Soyuz 5 problem was supposed
to have been fixed long ago.

Again, unconfirmed at this time. This should sort itself out over the next
few days.


Really? You really think we'll get a straight story out of the Russians?

I'm starting to think that in the next 5 years or less we'll lose a Soyuz
crew.


Still, NASA lost two orbiters and crews in the process by not getting
serious enough fast enough when faced with flight anomalies. One has to
wonder if Russia is doing the same with Soyuz.

It's called "foam logic" when NASA does it; I wonder what the term would
be for Soyuz...?



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