Leaning tower of falcon 9

"Fred J. McCall" wrote in message
...


And I'm stating that you are a fool and wasting my time.



You know Fred, unless you've got a gig I'm not aware of and getting paid for
this, you're under no obligation to respond to JF.
So he's not wasting your time. You are. You can stop responding to him any
time you want.
--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net

"Jeff Findley" wrote in message
...

Advocates of reusable launch vehicle tech have known this since the days
of the X-15 (earlier if you want to count the German rocket powered
fighter experience). It was rocket powered and the three copies which
were built flew so many times, I can never remember exactly how many
flights were made.

199. I always remember that because they were 1 short of 200 and did try for
it, but couldn’t get the conditions and everything in order before the money
finally ran out.

Jenkins (no surprise) has a good book on the X-15.

Jeff

--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net

JF Mezei wrote:

On 2016-06-20 21:55, Jeff Findley wrote:

SpaceX has recovered more than one stage. They've recovered four so
far.


If the first one that was recovered isn't the one which will fly first,
it means that it isn't really flyiable without refurb if another stage
is in a better condition.


It means no such thing. What it means is that SpaceX completely
dismantled it to see if the design goal was being met.

Read what SpaceX is saying.


I have no problem with SpaceX taking its time to examine things. But the
fact that no a single stage has been designated for a reflight yet means
nobody should be making claims that "it'd a proven technology, it will
be able to fly 10 times without refurb" etc etc.


You need to learn to read.

Read what I actually said.

Read what SpaceX is saying.


Just because there is higher degree of confindece that what SpaceX does
will happen (as opposed to NASA) doesn't mean that it is a done deal at
this point in time.


Still puling out your NASA lie, I see.


Since this is all new stuff, SpaceX has to develop validation tests for
those inspections. I am sure it os far mroe involved than looking at the
stage with a flashlight and using some Palmolive and s sponge to clean
off some burn marks.


I doubt they have to 'develop' anything. Presumably they already have
acceptance criteria for new stages. Those should work just fine as
acceptance criteria for used stages.


Consider the one that landed "leaning". If landing was hard enough to
cause a leg to crumple, they probably have to do more expensive tests to
ensure the rest of the stack is fine since the other legs transfered the
full force of landing.


Despite having it explained to you multiple times and eventually
claiming you understood it, you're back to making silly statements.
The leg didn't 'crumple'. The crush core collapsed just like it is
designed to do. There is no 'transferred force' from the landing leg
to the stage itself for ANY leg. And there is no 'stack'; it's a
single stage.

Read what people explain to you or stop wasting their time.

Read what SpaceX is saying.


And I would suspect that for each flight, they would have high speed
video of launch and several phases to detect any anomalies. Say they saw
something strange on takeoff, but stack landed fine. They will still
want to investigate.


And if unicorns come and **** rainbow dust all over things they will
no doubt want to investigate.


In fact, the crumpled leg one is likely a good candidate to help develop
inspection/testing procedures since the likelyhood of something being
broken is higher on that one.


Wrong. You still don't understand how the landing legs work.

Read what people explain to you and stop wasting their time.

Read what SpaceX says.


--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
-- Thomas Jefferson

JF Mezei wrote:

On 2016-06-20 21:59, Jeff Findley wrote:

I'm betting it's the huge backlog of launches to take care of. Paying
customers no doubt come first.


Would it be correct to state that production of new stage1s has been
"productized" and is now running smoothly ? If they need to increase
production rate, then it is a matter of duplicating machines and
employees. Easier said than done, but folks like Boeing, Airbus increase
production rates routinely.


Have you ever worked for Boeing or Airbus? Are you aware that rockets
are HAND BUILT, so increasing production requires acquiring new
workforce and bringing them up to adequate skill levels?


Would it be correct to state that recovery, inspection and attempts at
relaunch of used stage1s would be an R&D effort that would operate
separately from the production line ?


No.


If so, it would not be impacted by attempts at increasing production of
new parts for stage1.

However, budgets may be such that the R?D for reflight is limited
because not so strategically important/urgent. or maybe they reaslize it
is more work tnan they had thought.

Wher I can see some impact with production is in inspecting the landed
stages, they discover some part that is damaged and then tell production
folks to strenghten that part. (and then wait for that stage with
improve part to land so they can inspect it and perhaps use that one for
first reflight).

There are too many possibilities to draw any conclusions on this.


Only if you're stupid.

Learn to read and read what people are telling you.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn

"Greg \(Strider\) Moore" wrote:

"Fred J. McCall" wrote in message
.. .

And I'm stating that you are a fool and wasting my time.


You know Fred, unless you've got a gig I'm not aware of and getting paid for
this, you're under no obligation to respond to JF.
So he's not wasting your time. You are. You can stop responding to him any
time you want.


I always like to give them a chance before I ****can them as
worthless, Greg. That's the explanation for why I still respond to
****e like this from you, as well.


--
"Then tomorrow we may all be dead. But how is that different
from every other day?"
-- Morpheus

In sci.space.policy Jeff Findley wrote:
They've done extensive tests of the Merlin engines, which should be
the "long pole in the tent" when it comes to reflights without
refurbishment.

Would the next pole be the welds in the plumbing, followed by
structure?

rick jones
--
I don't interest myself in "why." I think more often in terms of
"when," sometimes "where;" always "how much." - Joubert
these opinions are mine, all mine; HPE might not want them anyway...
feel free to post, OR email to rick.jones2 in hpe.com but NOT BOTH...

JF Mezei wrote:

On 2016-06-21 06:09, Jeff Findley wrote:

It should. There is nothing fundamental about a liquid fueled rocket
stage from an orbital launch vehicle that prevents reuse. It's just
that no one has *tried* all that hard to reuse one, until now.

And there is nothing fundamental about jet engines to prevent reuse. And
this is done every day by jetliners.


Well, DOH!


HOWEVER, the airlines and FAA learned via experience that jet engines
can only run so many hours before needing certain level of inspection,
and after another set of hours, require a heavy maintenance check.


No, they didn't learn that 'from experience'. They learned it from
what the engines and vehicles were designed to be able to do. Just
like SpaceX has 'learned' that they can relaunch at least 10 times.


Oh, and after a "hard" landing, the aircraft needs a maintenance check.


Just the landing gear and only if the landing is so 'hard' that it
exceeds the design specs of the aircraft.


So SpaceX will learn via experience how many times a stage can be
reflown with just a flashlight inpection, how hard a landing the stage
can take without needing more serious inspection and after how many
flights is a major inspection required (and whether such major
maintenance is economic or not).


No, they will CHECK via actual experience whether or not their design
goals are holding up. Engineering ain't wishful magic, Mr Mezei.


When you look at the Orbital ATK fireworks at Wallops, didn't they run
the engines to test them before ? All seemed fine and yet, engines failed.


What does that have to do with the price of tea in China?


Doing a flight test (including landing) of engines 10 times is cool. But
you really need to test until they fail.


No you don't.


There is a big difference if
they fail on the 11th simulation vs on the 25th simulation.


Are you talking testing or simulation? They're not the same thing.


(on the
25th, it means that when you fly the 10th flight, the engines are still
far from failure).


Maybe. Maybe not.


fired on the test stand to test and qualify them. There is no
fundamental problem here that needs solving.

It is a question of validating the predictions. They've weeded out the
problems they know about. They haven't weeded out problems they don't
know about YET.


And may never know about them and thus never weed them out.


It could very well be that they can do 25 flights instead of 10. Or it
may be just 5. It could very well be that a major inspection can extend
the life of stage by X more flights, but still remains to be seen if
that major inspection is economically sound or if building a new one
ends up cheaper.


And maybe unicorns will fart magic rainbow dust all over everything.
Do you know ANYTHING about how actual engineering works?


Building new ones may present advantages if there are continuing
improvements to the rocket being made, at which point, the older rockets
without improvements are less attractive. There are a lot of variables
in this.


If you're constantly making hardware changes, every flight is a new
experiment. This is what SpaceX is trying to AVOID with things like
standard engine designs.



What "new stuff"? Visual inspections? Validation firings on a test
stand? What do you expect them to do between flights?

That is the question. How do you validate a rocket for reflight to
ensure nothing untoward happened during last flight. This is what SpaceX
needs to develop. This is more about procedures than engineering.


I'm sorry. I was apparently unclear. YOU 'VALIDATE' THEM THE SAME
WAY YOU VALIDATE A NEW ONE. They already have that. All clear now?


Possibly, but I doubt it since that's what the crushable inner core is
supposed to do. It wasn't unexpected at all.

If a leg "collapsed" because of hard landing, it still means it was a
hard landing.


The leg didn't 'collapse'. It did just what it was supposed to do.
The 'crush core' crushed. That's what it's there for. You obviously
either never understood this when it was explained to you in detail or
you have the long term memory of a ****ing mayfly.


If the collapsible core was fully compressed, it means
additional un-absorbed G forces would have been transmitted to the
stage.


Wrong.


Just just stating that because the gear absorbed some of the
excess G force doesn't mean that it absorbed all of it.


If it didn't the leg would have broken. It didn't. The leg and crush
core performed just like they were supposed to.

Pay attention when people explain these things to you.

Read what SpaceX says.

remaining ignorance elided

Buy a ****ing clue. Then phone a friend, if you have one, to explain
to you just what a 'clue' is and why they're useful.


--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
-- Thomas Jefferson

In sci.physics Fred J. McCall wrote:
JF Mezei wrote:

On 2016-06-21 06:09, Jeff Findley wrote:

It should. There is nothing fundamental about a liquid fueled rocket
stage from an orbital launch vehicle that prevents reuse. It's just
that no one has *tried* all that hard to reuse one, until now.

And there is nothing fundamental about jet engines to prevent reuse. And
this is done every day by jetliners.


Well, DOH!


HOWEVER, the airlines and FAA learned via experience that jet engines
can only run so many hours before needing certain level of inspection,
and after another set of hours, require a heavy maintenance check.


No, they didn't learn that 'from experience'. They learned it from
what the engines and vehicles were designed to be able to do.

Nonsense.

Early jet engines had a service life (Time Between Overhaul or TBO) of
10-15 hours.

It took decades of refinements to get TBO up to the current 10's of
thousands of hours, with inspection times and many parts replaced much
more often then that, and those times are STILL determined by operational
and maintenance records.

New engine designes usually have short maintenance and inspection
time requirements until the engine has proved itself in use.


--
Jim Pennino

On 6/21/2016 3:18 PM, wrote:
In sci.physics Fred J. McCall wrote:
JF Mezei wrote:

On 2016-06-21 06:09, Jeff Findley wrote:

It should. There is nothing fundamental about a liquid fueled rocket
stage from an orbital launch vehicle that prevents reuse. It's just
that no one has *tried* all that hard to reuse one, until now.

And there is nothing fundamental about jet engines to prevent reuse. And
this is done every day by jetliners.


Well, DOH!


HOWEVER, the airlines and FAA learned via experience that jet engines
can only run so many hours before needing certain level of inspection,
and after another set of hours, require a heavy maintenance check.


No, they didn't learn that 'from experience'. They learned it from
what the engines and vehicles were designed to be able to do.

Nonsense.

Early jet engines had a service life (Time Between Overhaul or TBO) of
10-15 hours.

It took decades of refinements to get TBO up to the current 10's of
thousands of hours, with inspection times and many parts replaced much
more often then that, and those times are STILL determined by operational
and maintenance records.

New engine designes usually have short maintenance and inspection
time requirements until the engine has proved itself in use.



the problem is vertical landing, all that fuel to slow you down, you
have to take round trip. better to land it like the shuttle, glide
down, no fuel needed.

OBW, military has done the vertical landing R+D for a while, but it took
the microprocesser age to get it smart enough

In sci.physics Sergio wrote:
On 6/21/2016 3:18 PM, wrote:
In sci.physics Fred J. McCall wrote:
JF Mezei wrote:

On 2016-06-21 06:09, Jeff Findley wrote:

It should. There is nothing fundamental about a liquid fueled rocket
stage from an orbital launch vehicle that prevents reuse. It's just
that no one has *tried* all that hard to reuse one, until now.

And there is nothing fundamental about jet engines to prevent reuse. And
this is done every day by jetliners.


Well, DOH!


HOWEVER, the airlines and FAA learned via experience that jet engines
can only run so many hours before needing certain level of inspection,
and after another set of hours, require a heavy maintenance check.


No, they didn't learn that 'from experience'. They learned it from
what the engines and vehicles were designed to be able to do.

Nonsense.

Early jet engines had a service life (Time Between Overhaul or TBO) of
10-15 hours.

It took decades of refinements to get TBO up to the current 10's of
thousands of hours, with inspection times and many parts replaced much
more often then that, and those times are STILL determined by operational
and maintenance records.

New engine designes usually have short maintenance and inspection
time requirements until the engine has proved itself in use.



the problem is vertical landing, all that fuel to slow you down, you
have to take round trip. better to land it like the shuttle, glide
down, no fuel needed.

Gliding down requires an aerodynamic configuration, i.e. wings and
control surfaces as well as retractable landing gear, which is a lot
of extra weight and complexity.

OBW, military has done the vertical landing R+D for a while, but it took
the microprocesser age to get it smart enough

So you need a microprocessor, a simple altitude radar, and throttles on
the engines, BFD.



--
Jim Pennino