Soyuz TMA-12 faulty

Jeff Findley wrote:

It's a given that expendables are more prone to failure than a reusable
vehicle of the same complexity.

Hold it.
"Same complexity"? It's not possible to make a reusable vehicle as
technologically simple as a expendable, as it has to do everything a
expendable has to do...plus be recoverable. So right there you have
added some sort of recovery system (parachutes, wings, landing gear,
etc.) plus, you have to add some sort of TPS on the recoverable part
that reaches orbit and returns to earth after releasing the payload.

The reason being that your expendable will
always suffer from the infant mortality problem far more than the reusable.
This is due to the simple fact that you simply cannot do a full test of an
expendable. It's one and only full test is, by definition, its one and only
flight to orbit.


Which can be good or bad depending on how you look at it; on the one
hand that will be its only flight so it will be all-new, and untested,
so a construction flaw may go unnoticed till it causes the loss of the
vehicle during the launch. On the other hand the reusable system needs
at least some inspection after each flight, particularly if it uses some
sort of TPS.
Don't be at all surprised if we lose another Shuttle prior to its
retirement, due to simply aging of the orbiter leading to something
faulty being missed between flights. That's already occurred in regards
to the wear problems on the wiring, and part of the actuators on the
rudder being installed backwards on at least one Shuttle.
This aspect became very noticeable in regards to the flight reports of
the X-15 in the book "At The Edge Of Space".
First, the X-15 have quite a few flight anomalies in early flights, as
kinks in the design and engineering are worked out.
Then it enters into a period where there are very few flight anomalies.
Then, as the program goes on, more and more anomalies reappear as the
individual aircraft age, and like a old car small things begin to
malfunction on each flight. A reusable launch vehicle is only as
reliable as its weakest point, and as the understrength RCC panels on
Columbia's wing leading edge showed, it's easy to miss a wear situation
that can destroy the vehicle with enough flights.
Since the DC-X never got anywhere near a orbital flight in it finished
Delta Clipper form, we don't know what the maintenance and inspection
requirements on it between flight would have been like.
Same goes for Venture Star.
The Shuttle was supposed to have pretty easy between-flight maintenance
requirements when proposed, but that certainly didn't turn out to be the
case when it actually entered service, and inspection and repair
requirements between flights became a major source of its terrible
economics as a launch vehicle.
Two aircraft your concept resembles (at best - and certainly a lot more
than a airliner or cargo plane) are the X-15 and SR-71. Neither of
theses was a "kick-the-tires-and-light-the-fires" type of maintenance
aircraft, and considering that your design would be going around four
times the speed of a X-15 once its upper stage reached orbital velocity
and would need a far more sophisticated (high heat tolerant and low
weight) TPS system to deal with reentry heating, their maintenance
requirements were far lower than what you propose.
If we'd built the X-20 Dyna-Soar and flown it a few times we probably
never would have built the Shuttle, after seeing how much inspection it
required between flights and extrapolating that up to something of
Shuttle size.
If you want a reusable launch system go back to the WvB Ferry Rocket
concept...just stick landing retros and parachutes on its stages and put
them down in the ocean. Once you realize how badly that affects your
orbital payload due to the weight of the recovery systems (like the
Russians figured out with their progressively more reusable Energia
system concept) you might figure out that expendables make a lot more
sense from a economic point of view when all is said and done.
About the only reusable booster concept I ever saw that looked like it
might have its head screwed on even halfways straight in regards to
economics was this thing: http://www.russianspaceweb.com/baikal.html
And all that was was a reusable first stage at best, so it didn't need
an involved and weighty TPS.

I'll agree that a sane reusable launch vehicle has not yet been built;
however, that's not proof that such a vehicle isn't possible.


No, but I'd like to see even a rough design as to how it's done.
Several countries have been batting their heads against the reusable
launch vehicle wall since the mid 1950's - early 1960's (US, Russia,
Britain, France, Germany, Japan, and China) and despite the profits that
can be expected from a low launch cost per pound in LEO for commercial
payloads alone, none of them has got even close to making it work in
reality.
Initial development cost alone to design and build such a system (if
even technically and economically feasible on a lowered actual launch
cost) is very high indeed, and that too has to be included in the
economics of it, since it has to be ameliorated by the payload launch
profits the system will carry once operational.
The classic case is the Concorde SST; once built it was actually was
capable of holding its own (barely) in a economic sense in regards to
ticket sales versus operating costs, but it never came anywhere near
recouping its development costs.

The closest we've come so far in an operational launch system are aircraft
used to drop expendable launch vehicles like Pegasus. Everything else
approaching sane reusability in rocket powered vehicles have been
experimental vehicles like the X-15 and the DC-X/XA.


And like you stated before, there may be a very good reason for that...
that's it's not economically feasible to build a reusable system with
today's technology. to make it possible either the engine isp needs to
be upped significantly or structural and TPS weight to be dropped
significantly. either of those would give the mass margin needed to
build a robust and fairly simple reusable launch vehicle, something like
a orbital C-130 cargo plane.
There might be some news on the structural side of the equation
regarding carbon nanotubes:
http://www.defensetech.org/archives/cat_armor.html
If they would maintain their strength characteristics at high
temperatures, then this might be a pretty nifty approach to a woven,
very lightweight and robust TPS... if you could figure out how to
convert its tensile strength into compression and shear strength equally
as high, then you could build a extremely lightweight and strong airframe.
Of course this implies that you can manufacture it at fairly low cost
per pound; it's not going to help if you can build a spacecraft out of
it that's really something, but it costs around a million dollars per
square inch of structure on average to build.
Still, if you get it into large-scale production at a decent cost with
those properties, it would change the whole world overnight far more
than the move from wood to iron, iron to aluminum, or aluminum to
composites ever did.
There's very few things you _couldn't_ build with a substance like that,
and one can picture a car whose whole body and frame (even engine block?
Carbon is a good conductor) might weigh around two hundred pounds total.
Which is going to work great till the first high wind comes along while
you are driving. Then you blow right off of the road.
If nothing else, this argues for battery-driven cars, if for the
ballast aspect alone if no other. :-D

Pat

On Thu, 29 May 2008 03:07:51 -0500, Pat Flannery
wrote:

Jeff Findley wrote:

It's a given that expendables are more prone to failure than a reusable
vehicle of the same complexity.

Hold it.
"Same complexity"? It's not possible to make a reusable vehicle as
technologically simple as a expendable, as it has to do everything a
expendable has to do...plus be recoverable. So right there you have
added some sort of recovery system (parachutes, wings, landing gear,
etc.) plus, you have to add some sort of TPS on the recoverable part
that reaches orbit and returns to earth after releasing the payload.

I'm confused. Isn't this discussion about the Soyuz capsule? The
booster was expendable, and maybe the capsule wasn't reusable,
but it was certainly intended to be recoverable. Might even be
reusable, as a Gemini capsule was, although that wasn't part of the
original intent.

Maybe I'm just not following along closely enough. I'm not sure the
Soyuz spacecraft should be more prone to failure because they are
individually crafted by artisans, and each is a one-off thing with no
previous experience or testing of the craft. They are essentially
manufactured on an assembly line. Sure, while Atlantis or Discovery
isn't on its "one and only flight to orbit", Soyuz by now should
pretty much be "type certified". Unless something has been altered
in its design or manufacture since the last one, the outcome shouldn't
change. On the other hand, there's nothing to say that a change in
the processing, and in some aspects "remanufacturing" of our
"reusable" orbiters will bring same results as the last flight. It
seems like the two overlap so much as to not really make much
difference...

Dale

I fear this post's formatting be all messed up

Dale Carlson wrote:
On Thu, 29 May 2008 03:07:51 -0500, Pat Flannery

wrote:

Jeff Findley wrote:

It's a given that expendables are more prone to failure than a
reusable vehicle of the same complexity.

Hold it.
"Same complexity"? It's not possible to make a reusable vehicle as
technologically simple as a expendable, as it has to do everything
a
expendable has to do...plus be recoverable. So right there you have
added some sort of recovery system (parachutes, wings, landing
gear, etc.) plus, you have to add some sort of TPS on the
recoverable part that reaches orbit and returns to earth after
releasing the payload.

I'm confused. Isn't this discussion about the Soyuz capsule? The
booster was expendable, and maybe the capsule wasn't reusable,
but it was certainly intended to be recoverable. Might even be
reusable, as a Gemini capsule was, although that wasn't part of the
original intent.

The "capsule" that is recovered is only part of the spacecraft.
Making that reusable would have negligible effect on operations costs
as you'd still be throwing away an orbit module and a service module
on every flight. And even if the reentry module itself is 100 percent
reliable, a failure in a part external to it could still put it into a
flight condition that it could not survive.

The same was true of Gemini--most of the technological guts of Gemini
was in the Equipment Module that was destroyed on reentry on every
flight.

Maybe I'm just not following along closely enough. I'm not sure the
Soyuz spacecraft should be more prone to failure because they are
individually crafted by artisans, and each is a one-off thing with
no
previous experience or testing of the craft. They are essentially
manufactured on an assembly line. Sure, while Atlantis or Discovery
isn't on its "one and only flight to orbit", Soyuz by now should
pretty much be "type certified". Unless something has been altered
in its design or manufacture since the last one, the outcome
shouldn't
change. On the other hand, there's nothing to say that a change in
the processing, and in some aspects "remanufacturing" of our
"reusable" orbiters will bring same results as the last flight. It
seems like the two overlap so much as to not really make much
difference...

You're ignoring manufacturing defects and what's called in failure
analysis the "bathtub curve"--failure rates are high for items fresh
off the line, go down after a period of time, and remain low until
wear, fatigue, and other effects of long term operation start becoming
an issue.

Every experienced delivery pilot has a horror story or two about
things that were wrong with a type certified airplane brand new from
the factory.


--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

Pat Flannery wrote:

:
:
:Jeff Findley wrote:
:
: It's a given that expendables are more prone to failure than a reusable
: vehicle of the same complexity.
:
:Hold it.
:"Same complexity"? It's not possible to make a reusable vehicle as
:technologically simple as a expendable, as it has to do everything a
:expendable has to do...plus be recoverable. So right there you have
:added some sort of recovery system (parachutes, wings, landing gear,
:etc.) ...
:

Anything manned needs those, unless you don't want to reuse the crew,
either.

:
:... plus, you have to add some sort of TPS on the recoverable part
:that reaches orbit and returns to earth after releasing the payload.
:

Again, anything manned needs that, too, unless you don't want to reuse
the crew.

Remember, we're talking about a crew return vehicle here (or at least
that's where the discussion started)...

--
"Insisting on perfect safety is for people who don't have the balls to
live in the real world." -- Mary Shafer, NASA Dryden

Dale Carlson wrote:
I'm confused. Isn't this discussion about the Soyuz capsule? The
booster was expendable, and maybe the capsule wasn't reusable,
but it was certainly intended to be recoverable. Might even be
reusable, as a Gemini capsule was, although that wasn't part of the
original intent.


Sorta reusable; they put a new heatshield on it with the added hatch.
Any ablative heatshield needs to of course be replaced after ever
flight; the Russians took a crack at a reusable heatshield it their
post-Soyuz spacecraft designs but if never panned out in, particularly
since they came down on land, so the heatshield got squished on impact.
Our new Orion was supposed to have a reusable heatshield as originally
designed, but that got quickly dumped...the advantages of a single-use
ablative heatshield both in lower cost and the fact it can be dropped
from the reentry capsule as it descends to landing after reentry to
greatly reduce its landing weight...and the weight of the parachutes,
landing rockets, or airbags that cushion its final impact is just too
seductive to a designer who wants to keep the overall mass of the
spacecraft biased toward maximum mission-related use of weight and
greatest internal crew volume for a given spacecraft mass.
The Apollo CM's shape ad weight was a far less efficient way of doing
things than the Soyuz with its orbital module, descent module with
jettisonable heatshield, and descent module's "gumdrop" shape.
All three modules of the early Soyuz spacecraft weighed less in total
than the Apollo CM alone did - due to its large diameter and heavy
heatshield - while offering more internal crew volume than the CM
between the Soyuz's orbital and descent modules.
All the companies that bid for the CM production contract pointed out
the inefficiency of the squat-cone design for the CM to NASA due to the
large diameter and weight of the heatshield on its bottom... but NASA
was adamant...like getting a Ford Model T in any shade of black you
wanted, you could design any type of Apollo CM you wanted... as long as
it was a squat cone.
Why exactly we are replicating that design error and failure of
imagination in Orion is way beyond me, but apparently "everything old is
new again".

Maybe I'm just not following along closely enough. I'm not sure the
Soyuz spacecraft should be more prone to failure because they are
individually crafted by artisans, and each is a one-off thing with no
previous experience or testing of the craft. They are essentially
manufactured on an assembly line.

They are done in batches in a fairly short period of time and stored
till needed - no continuous production line is used to save costs.
Somewhere I've seen photos of around eight finished Soyuz wrapped up in
plastic in the production works, awaiting launch over a period of a
couple of years or so.

Sure, while Atlantis or Discovery
isn't on its "one and only flight to orbit", Soyuz by now should
pretty much be "type certified". Unless something has been altered
in its design or manufacture since the last one, the outcome shouldn't
change.

That will occur on TMA-13 - that's the first of the new production
standard series using far lighter and more capable computers to replace
the Argon-16 dinosaur that's presently used.
Remember the "ferrite donuts on wire grids" memory systems of the
computers of the mid-late 1960's?*
(And boy, if you want to feel old... most computer whiz-kids today don't
have clue about what I'm talking about when I mention them. I might as
well be doing math in Roman numerals on a clay tablet. Later we discuss
reel-to-reel tapes versus LPs as a means of getting the best sound from
our "Rock And Roll Music" collections. :-D )
I hate to tell you this, but that's what's up there on Soyuz TMA-12 at
the moment.
The basic technology of the present Soyuz TMA computer isn't only
inferior to that used on the Space Shuttle... it's inferior to that used
on Apollo...where they figured out how to put the donuts around flexible
wiring bundles to save space.

On the other hand, there's nothing to say that a change in
the processing, and in some aspects "remanufacturing" of our
"reusable" orbiters will bring same results as the last flight. It
seems like the two overlap so much as to not really make much
difference...


I'm very concerned about just how old they are getting in absolute
terms; KSC's climate is very conducive to corrosion, and frankly when
they were built we thought they would have been retired for a
second-generation system by now.
(IIRC, when they were built, they were supposed to serve from around
1978-2000, doing around 100 flights each in that time period.)

Dale

I fear this post's formatting be all messed up


Worked fine on Thunderbird.

* I'm trying to remember how this all worked - did it have a "1", "0",
and "2" state depending if the magnetic field was aligned in one
direction, neutral, or aligned in the other direction, so that it was a
trinary as opposed to a binary form of memory storage?

Pat

"Jan Vorbrüggen" wrote in message
...
It's a given that expendables are more prone to failure than a reusable
vehicle of the same complexity.

Just so - the question being: can a reusable vehicle of the same
complexity actually be built, or is it implicit in the reusablity that the
complexity is higher?

The devil is in the details. This is one reason I liked the DC-X/XA
approach. For landing, you use the same engines that you used to take-off.
There are no parachutes, parafoils, air bags, or other bits of hardware
needed for landing. Also, not having wings, rudders, and aircraft like
landing gear simplified things quite a bit.

It did have small aerodynamic flaps, but I believe that one of the test
objectives was to investigate combinations of different control techniques
including the flaps, attitude control thrusters, gimballing the engines, and
differential throttling of the engines. You wouldn't necessarily need all
four techniques. Unfortunately I don't have a reference handy which shows
any conclusions of this sort of testing.

By far the advocates of HTHL, air breathing, SSTO's win the prize for most
complex vehicle. Not only are the air breathing engines overly complex when
compared to rocket engines, the vehicle is required to stay *in* the
somewhat denser parts of the atmosphere longer to use its air breathing
engines to accelerate. On top of that, you still need a rocket engine in
there somewhere to circularize your orbit. Plus you need landing gear that
will support the vehicle on take-off, retract properly, then redeploy
without fail for landing. Add to that the need to have wings, rudders, and
all sorts of other movable surfaces to make it stable from subsonic take-off
and landing to hypersonic speeds. All in all, very complex.

In particular, NASP did nothing to further the cause of cheaper access to
space. It was sold as a hypersonic cruise vehicle *and* a launch vehicle
(which is an acceleration type of flight). These are two vastly different
sets of requirements which would result in two vastly different vehicles.
Reminds me of Shimmer, the fictional floor wax and dessert topping which was
the centerpiece of a classic Saturday Night Live skit.

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

On May 29, 6:03*am, "J. Clarke" wrote:
Dale Carlson wrote:
On Thu, 29 May 2008 03:07:51 -0500, Pat Flannery

wrote:

Jeff Findley wrote:

It's a given that expendables are more prone to failure than a
reusable vehicle of the same complexity.

Hold it.
"Same complexity"? It's not possible to make a reusable vehicle *as
technologically simple as a expendable, as it has to do everything
a
expendable has to do...plus be recoverable. So right there you have
added some sort of recovery system *(parachutes, wings, *landing
gear, etc.) plus, you have to add some sort of TPS on the
recoverable part that reaches orbit and returns to earth after
releasing the payload.

I'm confused. Isn't this discussion about the Soyuz capsule? The
booster was expendable, and maybe the capsule wasn't reusable,
but it was certainly intended to be recoverable. Might even be
reusable, as a Gemini capsule was, although that wasn't part of the
original intent.

The "capsule" that is recovered is only part of the spacecraft.
Making that reusable would have negligible effect on operations costs
as you'd still be throwing away an orbit module and a service module
on every flight. *And even if the reentry module itself is 100 percent
reliable, a failure in a part external to it could still put it into a
flight condition that it could not survive.

The same was true of Gemini--most of the technological guts of Gemini
was in the Equipment Module that was destroyed on reentry on every
flight.

Maybe I'm just not following along closely enough. I'm not sure the
Soyuz spacecraft should be more prone to failure because they are
individually crafted by artisans, and each is a one-off thing with
no
previous experience or testing of the craft. They are essentially
manufactured on an assembly line. Sure, while Atlantis or Discovery
isn't on its "one and only flight to orbit", Soyuz by now should
pretty much be "type certified". Unless something has been altered
in its design or manufacture since the last one, the outcome
shouldn't
change. On the other hand, there's nothing to say that a change in
the processing, and in some aspects "remanufacturing" of our
"reusable" orbiters will bring same results as the last flight. It
seems like the two overlap so much as to not really make much
difference...

You're ignoring manufacturing defects and what's called in failure
analysis the "bathtub curve"--failure rates are high for items fresh
off the line, go down after a period of time, and remain low until
wear, fatigue, and other effects of long term operation start becoming
an issue.

Every experienced delivery pilot has a horror story or two about
things that were wrong with a type certified airplane brand new from
the factory.

--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)- Hide quoted text -

- Show quoted text -

This is the source for two proverbs in aviation:

Never fly the A version of anything

Never fly a plane if the paint hasn't worn off the rudder pedals.

Blue skies to all and take care . . .

John

On Thu, 29 May 2008 09:21:46 +0200, in a place far, far away, Jan
Vorbrüggen made the phosphor on my
monitor glow in such a way as to indicate that:

It's a given that expendables are more prone to failure than a reusable
vehicle of the same complexity.

Just so - the question being: can a reusable vehicle of the same
complexity actually be built, or is it implicit in the reusablity that
the complexity is higher?

Obviously a reusable will have to be more complex than an expendable,
because it will have systems required for recovery that an expendable
doesn't have. But there is much more to cost estimation than
complexity. Flight rate is the strongest driver in reducing launch
costs.

On May 29, 7:29 pm, "Jeff Findley"
wrote:
Not only are the air breathing engines overly complex when
compared to rocket engines

Is it true that a typical liquid-fuelled rocket engine is
*conceptually* simpler than a basic turbofan but *as flown* somewhat
more complex?

Jeff Findley wrote:
"Jan Vorbrüggen" wrote in message
...
It's a given that expendables are more prone to failure than a
reusable vehicle of the same complexity.

Just so - the question being: can a reusable vehicle of the same
complexity actually be built, or is it implicit in the reusablity
that the complexity is higher?

The devil is in the details. This is one reason I liked the DC-X/XA
approach. For landing, you use the same engines that you used to
take-off. There are no parachutes, parafoils, air bags, or other
bits
of hardware needed for landing. Also, not having wings, rudders,
and
aircraft like landing gear simplified things quite a bit.

May be simpler but how much payload do you sacrifice to tanker the
fuel needed for landing? The concept might be viable if you're
throwing atom-bombs out the back for power but for conventional
chemical fuel a single-stage vehicle has enough trouble just
struggling into orbit, without having to carry a payload or tanker
enough fuel for a powered landing.

It did have small aerodynamic flaps, but I believe that one of the
test objectives was to investigate combinations of different control
techniques including the flaps, attitude control thrusters,
gimballing the engines, and differential throttling of the engines.
You wouldn't necessarily need all four techniques. Unfortunately I
don't have a reference handy which shows any conclusions of this
sort
of testing.

By far the advocates of HTHL, air breathing, SSTO's win the prize
for
most complex vehicle. Not only are the air breathing engines overly
complex when compared to rocket engines, the vehicle is required to
stay *in* the somewhat denser parts of the atmosphere longer to use
its air breathing engines to accelerate. On top of that, you still
need a rocket engine in there somewhere to circularize your orbit.
Plus you need landing gear that will support the vehicle on
take-off,
retract properly, then redeploy without fail for landing. Add to
that the need to have wings, rudders, and all sorts of other movable
surfaces to make it stable from subsonic take-off and landing to
hypersonic speeds. All in all, very complex.

In exchange for which you don't need to lift 2/3 of the vehicle mass
in oxygen to get it off the ground.

In particular, NASP did nothing

You could have stopped there.

to further the cause of cheaper
access to space. It was sold as a hypersonic cruise vehicle *and* a
launch vehicle (which is an acceleration type of flight). These are
two vastly different sets of requirements which would result in two
vastly different vehicles. Reminds me of Shimmer, the fictional
floor
wax and dessert topping which was the centerpiece of a classic
Saturday Night Live skit.

Since NASP was killed long before it produced even a prototype engine
design, the feasibility of the completed project is irrelevant.

Only two scramjets have ever been flown successfully, so it's not
clear what kind of potential that technology has. My guess is a lot
more than the naysayers claim.

--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)