Op 8-3-2007, heeft Derek Lyons verondersteld :
André, PE1PQX <pe1pqx_geenviagra@planet.nl> wrote:

Derek Lyons was zeer hard aan het denken :
"Jorge R. Frank" <jrfrank@ibm-pc.borg> wrote:

It's not like we had a significant experience base to go stale in the
first place Jorge. Not only did the Mercury-Gemini-Apollo series
overlap each other to a large degree, they were all essentially first
generation systems.[1] Each program experienced significant flight
anomalies, and in Apollo's case, had at least two inflight failures
(15 docking, 17 SPS) that could easily have lead to LOM or LOCV.

inflight failures: What about Apollo 13 (exploded O2 tank)??

I discounted Apollo 13 because the accident was caused by component
damage during handling - unlike 15 and 17 where the causes are unknown
and could easily be failure modes which are rare but inherent to the
design. Apollo 13 type accidents from human error can happen even in
a mature program, 15 and 17 type incidents we cannot classify as the
causes are unknown.

D.

Then I'd like to know what happened on Apollo 15 and 17, did not know
there were some accidents during those flights.

I dread another Mr. Fenyman interviewing NASA folks who believe Orion has a
1 in a 100,000 (or better) risk of mission failure based on sheer hope.

André, PE1PQX <pe1pqx_geenviagra@planet.nl> wrote:

15 was unable to dock to the LM during initial T&D - until 'brute
forced'.

17 suffered a failure of the primary control cables across
the gimbals between the SM and the SPS.

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

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

André, PE1PQX <pe1pqx_geenviagra@planet.nl> wrote:

Op 8-3-2007, heeft Derek Lyons verondersteld :
André, PE1PQX <pe1pqx_geenviagra@planet.nl> wrote:

Derek Lyons was zeer hard aan het denken :
"Jorge R. Frank" <jrfrank@ibm-pc.borg> wrote:

It's not like we had a significant experience base to go stale in the
first place Jorge. Not only did the Mercury-Gemini-Apollo series
overlap each other to a large degree, they were all essentially first
generation systems.[1] Each program experienced significant flight
anomalies, and in Apollo's case, had at least two inflight failures
(15 docking, 17 SPS) that could easily have lead to LOM or LOCV.

inflight failures: What about Apollo 13 (exploded O2 tank)??

I discounted Apollo 13 because the accident was caused by component
damage during handling - unlike 15 and 17 where the causes are unknown
and could easily be failure modes which are rare but inherent to the
design. Apollo 13 type accidents from human error can happen even in
a mature program, 15 and 17 type incidents we cannot classify as the
causes are unknown.

D.

Then I'd like to know what happened on Apollo 15 and 17, did not know
there were some accidents during those flights.

15 was unable to dock to the LM during initial T&D - until 'brute
forced'. 17 suffered a failure of the primary control cables across
the gimbals between the SM and the SPS.

On Wed, 07 Mar 2007 14:04:17 -0500, John Doe <jdoe@doe.org> wrote:

To a certain degree, yes. It will get mission designers back into the
practice of deep space operations sooner than a straight-to-Mars
project would, so we should (re-)learn many lessons before we start
the much higher risk Mars expeditions.

Going to the moon is like a weekend camping trip. Going to Mars is a real
expedition lasting more than a year.

You forget, NASA isn't re-doing Apollo sorties. Their plan is to build
a moonbase beginning with Landing No.1. That, most decidedly, will be
useful for follow-on Mars operations.

So will any sorties from the
Moonbase that later astronauts make for exploration missions. That
will really help pave the way for how to explore Mars.

Besides, if Mars is the real expedition and the moon is the weekend
camping trip, then we are currently just doing jaunts around the
block.

Sort of. LEO makes a lot of things easier due to the lack of gravity, but
in some ways it's a hindrance.

Jeff Findley wrote:
Sort of. LEO makes a lot of things easier due to the lack of gravity,
but in some ways it's a hindrance.

Unless NASA buys the Starfleet warp drive designs from Paramount Pictures,
it will still take a large number of months to get to and from Mars. And
much of that time will be spent in 0g. Experience on the ISS and Mir has
shown that many of the ECLSS systems are very hard to get right and remain
reliable over a long period of time when operated in 0g.

Mostly this has to do with the low reliability of the Elektron O2 generation
system. At this point, it's unclear if US O2 generator will be more
reliable. The low tech way out is just to launch with enough O2 for the
entire mission instead of trying to make it from waste water.

The reasons you cite are all
reasons why Orion *should* *theoretically* be safer. The only way Orion
can *prove* itself safer is via flight record. I don't believe Orion will
ever fly enough to prove that; at NASA's projected flight rates, it won't
hit 58 flights until around 2040 or so.

Of course ultimately new systems have to replace old ones. But I do agree.

And this is one reason why it bothers me we're losing the shuttle. It's
slowly become a mature system, and we're tossing it away for something newer
and shinier.

(Personally I'd argue we would have been "better" off treating the shuttle
more like the developmental system it was and simply fly more flights for
the sake of more flights. the focus on "we need a payload" so we can
justify the cost just made things worse. Had we dropped say another billion
a year on the shuttle program just to fly 25-50% more flights and mark them
as pure "development testing" probably would have created a far safer
system.)

Soyuz has two fatal accidents in 95 flights (1 in 47.5) and four fatalities
in 228[*] person-trips (1 in 57). Soyuz has had 85 safe landings since the
last fatal accident.

The space shuttle has had two fatal accidents in 117 flights (1 in 58.5)
and fourteen fatalities in 698 person-trips (1 in 49.9). It had 87 safe
landings between the 51L and 107 accidents.

Within the wide statistical uncertainty imposed by the small sample sizes,
those numbers are essentially identical

I dread another generation learning nothing about a spacecraft
accident except from Mr. Fenyman or his equivalent.

(Personally I'd argue we would have been "better" off treating the
shuttle more like the developmental system it was and simply fly more
flights for the sake of more flights. the focus on "we need a
payload" so we can justify the cost just made things worse. Had we
dropped say another billion a year on the shuttle program just to fly
25-50% more flights and mark them as pure "development testing"
probably would have created a far safer system.)

I dread another Mr. Fenyman interviewing NASA folks who believe Orion
has a 1 in a 100,000 (or better) risk of mission failure based on
sheer hope.

Sentimentally I'd agree. Realistically, although the shuttle *should* have
been designed and built as a "developmental" system, it was instead
designed and built to be "operational". This is evident all the way down
to
program terminology; true developmental systems have "cockpits" and
"instrument bays", not "crew cabins" and "payload bays". Unfortunately,
the
shuttle turned out rather too expensive to utilize in a truly
developmental
fashion, and has been assigned "operational" missions, of which two
remain:
assembling ISS and servicing HST. This will remain a source of conflict
between the program and the recommendations of both accident investigation
boards, unfortunately.

I dread another Mr. Fenyman interviewing NASA folks who believe Orion
has a 1 in a 100,000 (or better) risk of mission failure based on
sheer hope.

I already shudder when I hear people quote the 1:2000 LOCV risk for Orion
cited in the ESAS report as if it were fact.

--
JRF

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

"Derek Lyons"

I dread another generation learning nothing about a spacecraft
accident except from Mr. Fenyman or his equivalent.

You'd be lucky to have had a seat in one of his classes.

Moronic insult of a Nobel Laueate.