Telemetry data from SpaceX Youtube

On Tuesday, January 5, 2016 at 3:11:55 PM UTC-5, wrote:
Well I am no rocket scientist, But I clicked through the telemetry


I got to thinking about the implications of the SpaceX data. One huge design error of Falcon9 is the first stage release. Throttling down and coasting as the method of separation causes a "re-launch" at altitude. The rocket simply has to burn larger than it would of otherwise. This is just a fuel waste issue.

Orbits are supposed to be known. One huge reason is the necessity for emergency landing at anytime. This is a real man-rating issue. The capsule never achieved a stable orbit as seen in the telemetry data. Meaning it was on an elliptic one. It is necessary to detect the orbit not just burn to the proper injection location. Injection point is supposed to be a geographic point where a spacecraft engine shuts down onto a spherical orbit. The ascent to injection must also be spherical not elliptic. Retro in my mind are for changing orbits. Small burns to go from spherical to spherical form. Again elliptic orbits are hard to measure.

The use of a landing first stage causes a stage release requirement such that the is enough fuel to re-land. This compromises the injection location. I am not sure, but think the altitude for downrange separation is an issue concerning the proper ascent trajectory. It seems like a multicomponent ascent? Just a thought.

The guidance telemetry shows motion while it sits on the launch pad. This means bad non-man rate-able systems.

The reuse of any part is indication of poor judgement. Quality control for two scenarios is costly. One new engine and two rebuilt engine. Tearing the used engine down to rebuild it is more costly than building one. You can not just xray an engine and bless it ok because no cracks are seen. It needs a part by part xray and review. SpaceX is obviously engaged in feelgood technology.

The referenced paper requires a theoretical physicist to read it. But the first introduction diagrammatically shows a theory to simulate.

Back one step. SpaceX has no business attempting manned flight.

It has a 2D theory highly readable, use it. But be aware the NRL writer details a theory for earth rotation effects. The results indicate no need to use a rotation theory. I leaves this inference to a correct level of readership.

Even now there are still lessons to be written. A functional movement of mass center as fuel burns is approximated. In reality the emptying tilted canister function is required. This con-founder is likely corrected in the classified NRL systems. A solid engine will have an easy mass center function. A blessing for the small fry.

A human in Falcon9 with no reason in reality other than "feel good" is a serious judgement failure. It is a risk benefit for men to take. What is the discovery or testing to be? Everybody knows the correct spacecraft to field. The little two seat space shuttle is the craft of this time. It is automatic with man ability if the need is found. An "X" craft? on an Atlas. This is all that anybody should be redesigning and launching.

This is a reality world folks. One escape "X" craft for the space station also.
One crew in a full suit. And pods as suits for the evacuees.

There are to many judgement errors at SpaceX. A maned flight has to advance human reality. They are basically a feelgood government sponsored money waster.

People need to understand. Ablative re-entry is the correct theory. Landing re-entry gets the craft on the ground with no cargo human or material.

In article ,
says...

On Tuesday, January 5, 2016 at 3:11:55 PM UTC-5, wrote:
Well I am no rocket scientist, But I clicked through the telemetry


I got to thinking about the implications of the SpaceX data.
One huge design error of Falcon9 is the first stage release.
Throttling down and coasting as the method of separation causes
a "re-launch" at altitude. The rocket simply has to burn larger
than it would of otherwise. This is just a fuel waste issue.

Right there, at the very beginning of your post, you've made a horrible
assumption. Why in the world would anyone want to minimize "fuel
waste" for a vehicle where fuel costs are LESS than 1% of launch
costs?!?!?!?

You have fallen into what Henry Spencer calls the "performance uber
alles" mindset. This mindset comes from assuming that launch vehicles
should be the same as missiles. Historically, this happened because the
first launch vehicles were missiles that were converted or adapted into
launch vehicles (e.g. Soyuz, Atlas, and Titan II). The implicit
assumption made was that "performance" is the most important metric to
optimize when designing a launch vehicle. That assumption is quite
simply *wrong* for commercial launch vehicles.

In order to capture the largest share of the launch market, the metric
to optimize is lowest cost per launch. This, of course, assumes that
you need to be able to actually launch the customer's payloads, so that
payload mass to orbit is a fixed value, not something to optimize.

Similarly, the size (height, width, dry mass, and etc.) of the launch
vehicle is not something to optimize either. Who cares how big it is as
long as it gets the payload to orbit!

So, what SpaceX has done is to deliberately make Falcon 9 much bigger
than "necessary". Falcon 9 Full Thrust has *more* performance than it
needs for most missions. So, it "sacrifices" that extra performance to
enable reuse of the first stage. If successful, reusing the first stage
could have the following benefits:

1. Reliability. Recovered stages can be inspected and test fired so
that any design or manufacturing defects can be discovered and corrected
on future vehicles. Not having your launches fail very often is a good
thing which customers and insurance companies appreciate. Expended
stages can't be inspected post flight because they are in pieces either
at the bottom of the ocean (for US launches) or scattered across very
sparsely populated areas (for Russian launches).

2. Costs. Recovered stages can be reflown. As long as the cost to
inspect and refurbish recovered stages is less than the cost of
manufacturing, testing, and shipping a new stage to the launch site,
SpaceX saves money. This money saved can be used to increase profits,
increase investment in the company, reduce customer launch costs, or any
combination of the above.

3. Investor confidence. A company which shows visible progress in new
tech can be quite attractive to investors. I'm fully aware that reusing
Falcon 9 first stages could fall short on #1 and #2 because first
generation reusability may not be completely successful, if at all.
But, these very publicly visible demonstrations of reuse shows progress
in new tech that can enable SpaceX to find investors for their
LOX/methane Raptor engine as well as a next generation (presumably
reusable) launch vehicle. I'm not the only one who believes this. Paul
Krugman wrote an article about the reinsurance of innovation in things
(as opposed to software and the Internet).

Things to celebrate, like dreams of flying Cars: Paul Krugman
http://www.masslive.com/opinion/inde...o_celebrate_li
ke_dream.html

From above:
Over the past five or six years, however - or at least this is how
it seems to me - technology has been getting physical again; once
again, we're making progress in the world of things, not just
information. And that's important.

I've snipped the rest of your post because the conclusions follow from a
flawed premise.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

In article ,
says...

wrote:

On Tuesday, January 5, 2016 at 3:11:55 PM UTC-5, wrote:
Well I am no rocket scientist, But I clicked through the telemetry


I got to thinking about the implications of the SpaceX data. One huge design error of Falcon9 is the first stage release. Throttling down and coasting as the method of separation causes a "re-launch" at altitude. The rocket simply has to burn larger than it would of otherwise. This is just a fuel waste issue.


Fuel is cheap, which is the point.

For Falcon 9, fuel costs are reportedly less than 1% of launch costs.
Any SpaceX engineer who was hell bent on minimizing "fuel waste" would
be fired. Aruging with the boss is not a good thing.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

Jeff Findley wrote:
Right there, at the very beginning of your post, you've made a
horrible assumption. Why in the world would anyone want to minimize
"fuel waste" for a vehicle where fuel costs are LESS than 1% of
launch costs?!?!?!?

No argument from me for the here and now. There is a certain
interesting irony though. As vehicle reusability does become routine,
fuel costs will "naturally" increase as a percentage of launch costs.
Particularly as vehicle reusability approaches that of commercial
aviation. Probably many years out though.

rick jones
--
denial, anger, bargaining, depression, acceptance, rebirth...
where do you want to be today?
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...

On Sunday, January 17, 2016 at 5:22:04 PM UTC-5, Rick Jones wrote:
Jeff Findley wrote:
Right there, at the very beginning of your post, you've made a
horrible assumption. Why in the world would anyone want to minimize
"fuel waste" for a vehicle where fuel costs are LESS than 1% of
launch costs?!?!?!?



Thanks for the comments. I was using "fuel costs" in another vein. Fuel to lift unused fuel is my usage. The cost is wasted cargo mass. The philosophy is to fuel for the usage. Adding stages to get to orbit is akin to adding fuel to the variable sized main fuselage. Multi-stage rockets are cost tradeoff with the efficiency of the variable fuel engine stage. i.e. one stage to orbit is one boundary with mass of tanks sans fuel, the other boundary to efficiency. The most efficient rocket always looses structural material i.e. walls as the flight proceeds. But variable wall mass is a compromise in another fashion i.e. container integrity.

In general an engine lofts a mass range. The Falcon9 obviously is not seriously considered to be used for a single little microbot type of cargo, i.e.10kg. So the general fuel for the mission statement is philosophic not engineering.

The use of theory to control the flight path is unavoidable. The rotating thread rod to change angle of thrust has a physical relation to thrust angle effect. So a data of prediction is???? Begging the question, "when is control data created?" Theory or experiment? Theory with control data record has always proven itself correct.

In sci.space.policy message -
september.org, Sat, 16 Jan 2016 11:57:11, Jeff Findley
posted:

In article ,
says...

wrote:

On Tuesday, January 5, 2016 at 3:11:55 PM UTC-5, wrote:
Well I am no rocket scientist, But I clicked through the telemetry


I got to thinking about the implications of the SpaceX data. One
huge design error of Falcon9 is the first stage release. Throttling
down and coasting as the method of separation causes a "re-launch"
at altitude. The rocket simply has to burn larger than it would of
otherwise. This is just a fuel waste issue.


Fuel is cheap, which is the point.

For Falcon 9, fuel costs are reportedly less than 1% of launch costs.
Any SpaceX engineer who was hell bent on minimizing "fuel waste" would
be fired. Aruging with the boss is not a good thing.

Stationary fuel at ground level is cheap. But fuel at MECO altitude and
velocity is not cheap.


--
(c) John Stockton, Surrey, UK. Turnpike v6.05 MIME.
Merlyn Web Site - FAQish topics, acronyms, & links.

On 1/18/2016 8:54 PM, Fred J. McCall wrote:
wrote:
Fuel to lift unused fuel is my usage. The cost is wasted cargo mass. The philosophy is to fuel for the usage.


The 'philosophy' is wrong and not what SpaceX plans to do. Fuel
(whatever it is used for) is cheap. Hardware is expensive. If you
can spend fuel to save hardware, that is a good deal. THAT is what
SpaceX wants to do

snip

As further evidence (for the proposition that use of fuel to save
hardware is the SpaceX objective) consider the latest version of Falcon
9 V1.1 which uses "densified" fuel:

http://spaceflight101.com/spacerockets/falcon-heavy/

Here *even more* fuel is being lost in terms of cargo mass, but allows
the V1.1 rocket with (first-stage) recovery a performance profile closer
to what the F9 V1.0 (Merlin-1D/Octaweb/non-densified) had without.
Clearly you can see the design preference and evolutionary direction.
These choices are not accidental.

Hope this helps.
Dave

On Saturday, January 16, 2016 at 11:53:52 AM UTC-5, Jeff Findley wrote:
Things to celebrate, like dreams of flying Cars: Paul Krugman
http://www.masslive.com/opinion/inde...o_celebrate_li
ke_dream.html

From above:
Over the past five or six years, however - or at least this is how
it seems to me - technology has been getting physical again; once
again, we're making progress in the world of things, not just
information. And that's important.


The thing I hate most about Krugman is when he pontificates on subjects he absolutely knows nothing about. It's bad enough when he's wrong in his own field, stay out of mine...

His miracle cure for global warming ain't here yet. And I assure you it ain't gonna be miracle fairy dust either or solar panels on the rooftops of New York or whatever else his "faith" tells him...

In article , says...

Jeff Findley wrote:
Right there, at the very beginning of your post, you've made a
horrible assumption. Why in the world would anyone want to minimize
"fuel waste" for a vehicle where fuel costs are LESS than 1% of
launch costs?!?!?!?

No argument from me for the here and now. There is a certain
interesting irony though. As vehicle reusability does become routine,
fuel costs will "naturally" increase as a percentage of launch costs.
Particularly as vehicle reusability approaches that of commercial
aviation. Probably many years out though.

Fuel costs won't become what I would consider significant until copies
of vehicles are flying on the order of 100 times before they are
retired. And even this depends heavily on how much it costs to
refurbish the vehicle versus building a new one.

I seriously doubt we'll see this level of reuse out of Falcon 9 first
stages, since it's a first generation reusable. I'd expect their next
engine and vehicle will incorporate the lessons learned in the Falcon 9
program.

One of the biggest mistakes NASA made with the space shuttle was to
declare it "operational" after only a few flights and to keep it flying
for decades despite the fact that it too was a first generation reusable
design and had many flaws which made reuse very expensive.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

In article id,
lid says...

In sci.space.policy message -
september.org, Sat, 16 Jan 2016 11:57:11, Jeff Findley
posted:

In article ,
says...

wrote:

On Tuesday, January 5, 2016 at 3:11:55 PM UTC-5, wrote:
Well I am no rocket scientist, But I clicked through the telemetry


I got to thinking about the implications of the SpaceX data. One
huge design error of Falcon9 is the first stage release. Throttling
down and coasting as the method of separation causes a "re-launch"
at altitude. The rocket simply has to burn larger than it would of
otherwise. This is just a fuel waste issue.


Fuel is cheap, which is the point.

For Falcon 9, fuel costs are reportedly less than 1% of launch costs.
Any SpaceX engineer who was hell bent on minimizing "fuel waste" would
be fired. Aruging with the boss is not a good thing.

Stationary fuel at ground level is cheap. But fuel at MECO altitude and
velocity is not cheap.

Excuse my language, but I'm calling bull****!

Fuel cost is paid when the vehicle is loaded and each pound of fuel
added to the vehicle costs the very same amount. Your wrong headed
thinking about "performance" and "fuel waste" is the sort of wrong
headed thinking that has kept launch vehicles expensive for decades.

Again, who cares how much fuel is "wasted" when its cost is *less* than
1% of launch costs? Falcon 9 could "waste" far more fuel than it does
now and still charge customers less than the competition, still get
payloads to orbit, and still make a profit.

The metric to optimize is overall launch cost and today fuel costs are
quite simply lost in the noise. A good engineer does not try to
optimize away a cost that is less than 1% of the overall cost.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer