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Old November 26th 18, 09:11 AM posted to sci.space.policy
Fred J. McCall[_3_]
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Default SpaceX gets FCC approval to deploy thousands more internet satellites

JF Mezei wrote on Sun, 25 Nov 2018
22:35:27 -0500:

On 2018-11-25 06:20, Fred J. McCall wrote:

Again, your deficient reading skills and defective intellect have
betrayed you, since neither one of us has said any such thing.



I'll just note that you 'cleverly' removed the 'thing' you claimed we
both said, which was NOT the following:


So, you're now denying stating that ground based fibre strand can't
support more than 100gbps ?

Are you still denying a fibre strand with WDM can support multiple
concurrent 100gbps links ?


Nope. You see, unlike you I am capable of actually paying attention
to what other people write.

Now, did you look up the bandwidth of the internet backbone links?


This discussion is happening because you denied current commercial
capaciies on ground based fibre links in order to support your claim
that the Starlink will compete against ground lasers


No we are not and you are a liar, since I never said any such thing as
the preceding (which you will now remove from your quote and claim the
'thing' is something else, as you did above).


You made those asserions without knowing at what capacity the magical
Musk lasers will have between satellites. (generally speaking, the
longer the distance between laser and receiver, the lower the capacity.


Since I never made any such assertion, you are a liar.


Then again, you don't even seem to iunderstand the difference between
capacity and speed of light.


I don't feel particularly responsible for how things 'seem' to your
defective intellect, which has obviously crossed two different
discussions.


No, you tried to claim it will be as limited as your Canadian service,
which is simply false.


Never claimed it would as AS limited. What I claimed is that Musk's
dream won't magically unleash unlimited capacity that will replace
ground based links.


Since no one said it would, what you 'claimed' was just a little
opaque to the rest of us who speak regular English.


The limited spectrum between ground and satellites
will limit capacity ...


No, that's not the limiting factor.


... and economics will limit how many ground stations
you can afford to have. (and eventually, the broadcast footprint of a
satellite betwene itself and ground station will limit how close ground
sations can be to each other, as well, if they re-use the same spectrum
as used for retail service, then each ground station will represent a
dead zone where you can't obtain retail service.


What utter poppycock! Or are you claiming to be rebutting something
no one has said again?


So they need to
strategically position their ground stations to not only be near ground
based Internet majors "hubs", but also to not prevent retail serviec to
those traders who will allegedly queue up for that reduced latency
service no matter the price.


You seem to be obsessed with 'ground stations' while ignoring
everything you've been told that network experts (of which I am not
one) have said about the Starlink network. Let me repeat some numbers
I've given before that I'm sure your goldfish mentality either never
comprehended or forgot as soon as you read it, Mayfly. Starlink (by
itself) has the capacity to handle 50% of the total internet backhaul
on the planet. Starlink (by itself) can handle 10% of the total
traffic for even the 'densest' geographic area.


In other words, if you want to sell London to New York links, you may
not be able to put ground stations near either city. If they use
different spectrum fr the uplink vs retail connections, then this is not
an issue, assuming the satellite that is above has 2 radios with
antennas pointed to ground, one for retail connections and one for the
uplink.


Yes, if an idiot like you designs the system, there will be all sorts
of problems. Fortunately, I suspect they're not hiring idiots like
you for that job.


Go look up the bandwidth of the internet backbone, you havering loon.


There is no single internet backbone. Go lookup what _the_ "Internet"
means. I'll be professional and omit gratuitous insults.


In other words, you don't even know enough to understand the question,
much less answer it.



You're actually arguing two different things here. One of them is
semi-valid. The other claims the laws of physics are incorrect.
Starlink WILL have lower latency. The laws of physics say so.


But you only take a very narrow view of latency. Much of the latency
isn't actual transit time but time through each router, especially when
they are congested. You are considering only transit time on a Geman
autobahn where the speed limit is speed of light. You fail to consider
the time spend waiting in queues at toll booths, and slowing down when
going through interchanges to switch to another road.


You don't seem to understand, well, much of anything. Nor do you seem
to be able to differentiate between me and Jeff. Nor do you seem to
understand how networks actually work (they're not highways and data
packets aren't automobiles, no matter what Al Gore may have said).


If Musk sells satellite to satellite retail service (which doesn't use a
ground station), then the 2 end points may have reduced latency, but it
also means all satellites must start acting as routers instead of
swicths since not all traffic is going to the satellite that has link to
a ground station.


What utter poppycock!


Introducing routing in each satellite adds latency.


You don't appear to understand the difference between a router and a
switch.


Yes, on the ground, New York to Los Angeles takes longer than New York
to Chicago. But there will be cases when latency to Los Angeles will be
less than latency to Chicago. (congested links for instance).


So what? The network experts are predicting that Starlink will
typically be around 25 ms latency. Now go check your connection (mine
is currently running around 22 ms).



Once again, BFR/BFS allows launching these satellites for less than
$40,000 each.


Vague empty fictional promise on twitter. Until BFR/BFS flies, we can't
know the cost to launch each kg of payload. Remember that those costs
include amortization of the development and testing costs. And those are
unknowns.


Horse****. Analysis by people who do rockets for a living. If
BFR/BFS comes anywhere close to its designed capability, you can get
reasonably close numbers for this.


The fact that we're talking about 12,000 of them and
producing several thousand of them a year will make them much cheaper
to build than current satellites.


That is like the argument that because the fur coat is on sale, you need
to buy it.


Horse****.


12,000 cheaper satellites could still be very much more
expensive than 1 very expensive satellite.


Yes, and monkeys might fly out your butt.


The A380 example I provided ...


Is irrelevant. Things that are different are not the same.


So, while SpaceX has excelled with their small Falcon9, it does not
automatically mean that they will excell at a rocket of a scale they
have never done before (and a BFS of a scale nobody has ever done before).


'Small' Falcon 9? Really? There is never a guarantee of success, but
that's certainly the way to bet in this case. They've proven out the
difficult technologies (tanks, engines).


Not so much. When has SLS ever flown the real operational article?


They'd have 1 test flight of SLS, haven't they ?


No, they haven't. The first test flight will (currently) be in 2020.


They've had drop test
of Orion. That is more than BFR/BFS.


OK, so we know gravity will affect Orion. This should not be a
surprise to anyone and I'm pretty sure we can bet that BFS will be
affected by gravity without dropping it to check.


Well, let's see. They've demonstrated they can build the tanks.


Do you REALLY know the actual results of the tank tests they have made?
Musk stated the exceeded the max pressure test in destructive testing.
This is good. But if BFR/BFS is to achieve the economics that are
promised, re-usability becomes essential for many many many flights. So
has SpaceX published results of how those tanks are doing in multiple
fill/empty cycles? If not, then nobody in the public can claim SpaceX
has the tanks succesfully tested and ready for production.


And we're back to the Mayfly ignorance of how science and engineering
works. For Mayfly, everything MUST fail until its operational, at
which point I guess he must always be astonished.



It will pretty much 'work as advertised' or they'll cancel it. It's
not going to be 'scaled back'. They're on the third (I think) design
iteration and it's gotten around 10% BIGGER, which is not 'scaling
back'.


10% bigger isn't necessarily good news. Could mean the thing will be
heavier than originally predicted.


I should have said "10% longer", but whatever. If it' "heavier than
originally predicted" (and it probably will be; most aerospace
vehicles are) one way to deal with that is get more fuel on board,
which you do by (tada) making the vehicle physically bigger to hold
more fuel. I suspect this is what is going on with the most recently
announced changes. BFR changed very little other than to get very
slightly longer. BFS on the other hand got significantly longer and
the engine configuration changed.



As for your 'devolve' path, that's rather like claiming that
if the Boeing 747 project had run into difficulties it would have
'devolved' into a project to produce 737s. It's a preposterous
notion.


Core 747 development was funded by the US military. When Military
decided to not buy it, Boeing decided to continue development and create
commercial passenger and cargo planes with it.


That's about half true. While the initial concept of the 747 came out
of a DoD competition (which Lockheed won and which became the C-5),
that doesn't mean that the military paid. Frequently initial design
studies are funded out of B&P money, which is internal to the company.
Since Boeing made it through the first downselect, that would likely
be where government money got significantly involved. Boeing didn't
"decide to continue development and create a commercial passenger and
cargo plane". That was pretty much always the plan, since they'd been
asked by airlines for a larger capacity aircraft.


The reason for the hump was to put the cockpit out of the way so cargo
can be loaded through the nose.


Again about half true. There are other ways to "put the cockpit out
of the way" and both Lockheed and Douglas did it differently than
Boeing. You know there's a passenger lounge up there, right?

And despite all that, it didn't become a Boeing 707 with an extra
fuselage (a design that was apparently actually proposed at one point
for the A-380; two A-340 fuselages pasted together side by side).


The 747 was state of the art for those days, so they knew how to
design/make it.


Nope. For example, it required new and much more powerful engines.


The A380 was beyond state of the art, hence Airbus
having to delay the official project launch for many years in the 1990s
until they develop enough new tech to make the 380 possible.


According to Airbus, the major cause of delay was "the complexity of
the wiring in the aircraft". Now, how long had we been putting wiring
in aircraft at that point? To that I would add the mad merry go round
of structures that had to go on among the countries involved so that
everyone would get their piece of the industrial pie.

Note that Boeing had been involved in a design study for a Very Large
Commercial Transport aircraft with several of the companies that
teamed for the A-380 effort. Boeing withdrew after a couple of years
because they projected development would cost around $15 billion and
didn't think that could be recovered by the commercial market for such
and aircraft.


The problem is that by pushing the state of the art only till the plane
can be airworthy, it didn't push enough and the 380 ended up being too
heavy to deliver on all the prmised performance advantages over smaller
planes.


They couldn't figure out how much the wiring would weigh? How long
have we had gravity?

Airbus mismanaged the whole thing, too. Remember that $15 billion
that Boeing thought it would take to develop such an aircraft? Airbus'
initial estimate was €8.8 billion, around 20% less than Boeing thought
it would take (and without all the round robin bull**** with
structures that Airbus did). Actual cost? Somewhere north of £16
billion, or around 66% MORE than Boeing estimated. Because of WIRING.


SpaceX is in the same sitiuation.


Not even close. Again, they've already tested the hardest parts.


It is pushing the state of the art to
design/built the BFR/BFS, and in the case of BFS, pushing it by a huge
amount. How far they can afford to push the state of the art remains to
be seen amd that will determine not wheter it is built or not, but how
much cargo it can carry or how many times it can be re-used.


Wrong. If they can't get close to the current design performance,
they just won't build them. What do you think would be the point?


And the longer it takes to develop and test the new technologies that
are required for BFR/BFS, the more cash it takes.


Usually true, but not a given. However, this is why I expect around a
2 year slide in BFR/BFS and use the $10 billion upper limit of the
range for development costs instead of the optimistic lower end of
SpaceX figures (orbital flights in 2020, Mars cargo flights in 2022,
manned Mars mission in 2024 with a development cost of $3 billion).


The difference between the two positions is that we assume they're
going to try to do what they've said they're going to do and look at
progress while you assume they won't try to do what they've said


I haven't said that.


Not in so many words, but your constant caviling makes your position
obvious.


Your unwaivering blind faith in Musk pushes you to
insult anyone who doesn't have the same faith that he will deliver
BFR/BFS exactly as promoted.


You're lying again.


If Musk announced he was about to develiop a Galaxy clas sstarship with
transparent aluminium windows and a warp engine, you'd believe him
because in the past, SpaceX has always delivered.


Well, nothing succeeds like success, so if he announced such a thing I
wouldn't bet against him. Of course, I could engage in the same sort
of 'logic' you use above and say that if Musk announced he was going
to take a **** you'd have dozens of medical reasons for why he might
not be able to.


Musk is moving to unchartered territory and I accept the BFR/BFS project
may or may not turn out exactly as promised. And I asccept that not
everything Musk tweets is factual, a lot of its is just PR stunts to
anmuse his twitter audience.


Your inability to tell the difference is YOUR problem.


Only because NASA is dragging their feet on the manned version and
they haven't used up all the Cargo Dragon V1 in stock yet so don't
need to fly the cargo version.


The fact, beyond your faith is that Dragon 2 has not flown. It may be
all ready and held only by paperwork, or it may have failed some NASA
tests and needs further fine tuning. Not the type of thing that is made
public so you or I can't know either way. So blind faith in Dragon 2
being ready is wrong.


It's the former and it's public. Testing was completed successfully a
while back and the tested hardware has been delivered to the Cape.
Both the unmanned test and the first manned flight are firmly
scheduled and NASA doesn't do that on blind faith.

But perhaps monkeys will fly out your butt...


--
"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