Super-heavy lift reusable launcher

Ian Parker wrote:

:On 10 Aug, 11:50, Fred J. McCall wrote:
: Ian Parker wrote:
:
: :On 9 Aug, 23:35, Fred J. McCall wrote:
: : Ian Parker wrote:
: :
: : :
: : :You are assuming that heavy lift is need for SSP. In fact what you
: : :require is the phase locking of small (a few Kw) units.
: : :
: :
: : That may be what YOU require, but is anyone proposing building one
: : that way?
: :
: : Why do I doubt it?
: :
: :
: :Its the onlt logical way to do it. Having large parabolic mirrors at
: :GEO is totally impractical.
: :
:
: Oh, is it? *Why is that?
:
: While you're at it, why do you need "large parabolic mirrors at GEO"
: for SSP?
:
: --
: "Some people get lost in thought because it's such unfamiliar
: *territory."
: * * * * * * * * * * * * * * * * * * * --G. Behn
:
:There are 2 basic approaches to beaming energy. One is to have a large
:fixed mirror. The other is a phase locked array. I am discussing phase
:conjugation and it is very interesting. Instinct tells me that a large
:fixed mirror cannot be the way forward.
:

True, but that is primarily because using visible light for beaming
power is not "the way forward". How do you propose to solve the minor
problem with that stuff called 'cloud cover'?

All this was worked out long ago. There's no reason to change it now.

--
"The reasonable man adapts himself to the world; the unreasonable
man persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man."
--George Bernard Shaw

In terms of size, here's an interesting chart

http://www.projectrho.com/rocket/rocket3f2.html

The engines I've talking about would have a bell diameter that would
neatly cover the city bus and would be about as tall as the Millenium
Falcon. They would attach to a structure about the size of the Eiffel
Tower.

The payload could easily loft three fully loaded Saturn Vs into an
escape trajectory at the same time - not that you would actually do
that.

Stage layout and operation is very similar to this vehicle

http://www.astronautix.com/lvs/rombus.htm

but larger..

On 10 Aug, 12:36, Fred J. McCall wrote:
Ian Parker wrote:

:On 10 Aug, 11:50, Fred J. McCall wrote:
: Ian Parker wrote:
:
: :On 9 Aug, 23:35, Fred J. McCall wrote:
: : Ian Parker wrote:
: :
: : :
: : :You are assuming that heavy lift is need for SSP. In fact what you
: : :require is the phase locking of small (a few Kw) units.
: : :
: :
: : That may be what YOU require, but is anyone proposing building one
: : that way?
: :
: : Why do I doubt it?
: :
: :
: :Its the onlt logical way to do it. Having large parabolic mirrors at
: :GEO is totally impractical.
: :
:
: Oh, is it? *Why is that?
:
: While you're at it, why do you need "large parabolic mirrors at GEO"
: for SSP?
:
: --
: "Some people get lost in thought because it's such unfamiliar
: *territory."
: * * * * * * * * * * * * * * * * * * * --G. Behn
:
:There are 2 basic approaches to beaming energy. One is to have a large
:fixed mirror. The other is a phase locked array. I am discussing phase
:conjugation and it is very interesting. Instinct tells me that a large
:fixed mirror cannot be the way forward.
:

True, but that is primarily because using visible light for beaming
power is not "the way forward". *How do you propose to solve the minor
problem with that stuff called 'cloud cover'?

All this was worked out long ago. *There's no reason to change it now.

--
"The reasonable man adapts himself to the world; the unreasonable
*man persists in trying to adapt the world to himself. Therefore,
*all progress depends on the unreasonable man."
* * * * * * * * * * * * * * * * * * * --George Bernard Shaw

Clould cover is a sighting problem. It all depends where you are
beaming to. If you want to electrolyse water you simply site yourself
where there is little clould cover. If again you want to power
aircraft at 10,000m there is little clould.

William Mook is championing light. I am not convinced of the
advantages over microwaves myself although we should, I think, have an
open mind. The same arument about phase coherence occurs with
microwaves too.


- Ian Parker

On 10 Aug, 12:26, wrote:
On Aug 10, 6:20*am, Ian Parker wrote:

On 10 Aug, 10:25, wrote:

Yes, but remember that receiver and transmitter have to exchange
photons in order to remain locked - so,the power beam will lag the
motion of the receiver by whatever the delay time is. * For GEO this
is 1/4 second. *At 930 miles altitude, this is 1/100th second.

That is true. Having posted I was going to add that rider. You indeed
need to extrapolate 2d/c ahead. Thus a degree of computation is
unavoidable.

Best done photonically - with the photons themselves in a photonic
medium - whether microwave or optical.

Possibly, but I don't think this is intuitively obvious. What you seem
to be doing here and further on is inventing an optical computer.
People have attempted to design them. An optical computer can (in
theory) solve problems involving Fourier Transforms faster than
standard digital computers.

Leading question. Can we reduce an extrapolation problem to a series
of Fourier Transforms? Yes we can. We put old data in and the Fourier
Transform provides an extrapolation.

However I regard this as really getting beyond the scope of this
discussion. We should not be diverting intio new computing paradymes.

I read through the rest. The basic principle of an array in physical
optics is that your light intensity is a product of two things. It is
the envelope of a single element * The envelope provided by the array
viewed as point sources. Thus your individual element is going to have
a fair spread.

Check on the physics of sparse arrays of elements. *You can focus
within the Rayleigh criterion - but the efficiency with which you do
it goes to hell in a sparse array rather quickly - even if you
resolved all the other open issues.

Simple conjugacy gives a sub optimal solution in the sparse case - or
does it? A sparse array gives us subsidary maxima and minima. We want
to minimise enery in these subsidery maxima.

Actually I am beginning to feel that conjugacy is optimal. I will
think some more about it. I feel that a paper could be written on the
subject. What we need to show is that depatures from conjugacy give a
worse solution. I am working on this one.

You are indeed correct in saying that you need equipment for detecting
the phase of the source.

Which is achieved automatically by putting a phase conjugate mirror on
the backside of a laser cavity, and a phase conjugate window on the
front. *You can get 1 million to 1 trillion power gain in such a
system

This is best done by having a unit which
consists of a camera with a Michaelson interferomer.

If all you want to do is detect. *However the simplest thing to do is
to have a powerful laser equipped with nonlinear mirrors and front
window and illuminate it with a bandgap matched laser from far away.
The output of the laser will then direct itself immediately along the
pilot beam in the opposite direction.

The only computation is done by the designer of the control circuit.
Knowing the power laser's properties, we know how long it takes for
power to build up at the reciever, so power level is easily controlled
by controlling the duration of the pulse - then the rate of pulse
determines overall power.

I think you will find that bang bang control systems do NOT give
optimal solutions. This is provable. A conjugacy mirror must send the
same AMPLITUDE back,

An individual
subunit (consisting of a number of units) would have a resolution of
1km.

Your efficiency with a sparse array would be very very low -
furthermore - you have instant response with a nonlinear window - even
if constructed from microwave elements using linear op amps - and the
system is more reliable besides.

For a microwave system yes. You can have one transmitter, one
receiver. For an optical array you can't. This BTW is not a sparse
array in normal sense of the term. All transmitters will form a non
sparse array.


- Ian Parker

wrote in message
...
In terms of size, here's an interesting chart

http://www.projectrho.com/rocket/rocket3f2.html

The engines I've talking about would have a bell diameter that would
neatly cover the city bus and would be about as tall as the Millenium
Falcon. They would attach to a structure about the size of the Eiffel
Tower.

The payload could easily loft three fully loaded Saturn Vs into an
escape trajectory at the same time - not that you would actually do
that.

Stage layout and operation is very similar to this vehicle

http://www.astronautix.com/lvs/rombus.htm

but larger..

============================================

Well, well, well. There is another of those wonderfully
future oriented things "we" discarded in the late '60's
and in the '70's, so as to free up money for that war in
Vietnam. The effect of choices then upon the present
and future now, is plain to see. ...Will this list ever
end? ??


Titeotwawki -- mha [sci.space.policy 2008 Aug 10]

"Alan Erskine" wrote in message
...
"Pat Flannery" wrote in message
news

At least Sea Dragon got into that engine size category:
http://www.astronautix.com/lvs/searagon.htm

Again; imagining something and actually making it happen are two
different things.

===========================================

OK on the obviosity. What's the point?

Titeotwawki -- mha [2008 Aug 10]

"Fred J. McCall" wrote in message
...
Ian Parker wrote:
:
:You are assuming that heavy lift is need for SSP. In fact what you
:require is the phase locking of small (a few Kw) units.
:

That may be what YOU require, but is anyone proposing building one
that way?

Why do I doubt it?

--
"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

========================================

Note on that quote. Francis Bacon said it better:

"Truth will sooner out from error than from ignorance."

Titeotwawki -- mha [sci.space.policy 2008 Aug 10]

On Aug 10, 3:23 am, Ian Parker wrote:
On 9 Aug, 23:35, Fred J. McCall wrote:



Ian Parker wrote:

:
:You are assuming that heavy lift is need for SSP. In fact what you
:require is the phase locking of small (a few Kw) units.
:

That may be what YOU require, but is anyone proposing building one
that way?

Why do I doubt it?

--
"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

Its the onlt logical way to do it. Having large parabolic mirrors at
GEO is totally impractical.

But not as from a Selene/moon L1 tether dipole element that's holding
its termination pod or array of laser cannons at 2r from Earth.

This Earth-moon L1 tether dipole element is originated at roughly
58,000 km from the moon, whereas it's LSE-CM/ISS (sort of tethered
Clarke Station, except much larger and considerably massive) is
efficiently station-keeping and sunny 97+% of the time, not to mention
the secondary/recoil worth of the Selene/moon IR.

Since there's no limits as to the taper or given volume of this
primary lunar elevator tether, there's no problems with artificially
establishing this tether within existing material specs.
http://en.wikipedia.org/wiki/Lunar_space_elevator
"Unlike the earth space elevator, the materials for the lunar space
elevators don’t require a lot of strength. The elevator can be made
with materials available today. Carbon nanotubes aren’t required to
build the structure."

http://www.lpi.usra.edu/publications...aryland01b.pdf

http://en.wikipedia.org/wiki/Lunar_space_elevator

http://www.star-tech-inc.com/papers/als/lunar.pdf

And there's lots of other independent research besides that of my LSE-
CM/ISS, though all of which is officially ignored and banished by the
mainstream cabal that's still in a full blown damage control of their
DARPA need-to-know and nondisclosure policy.

~ Brad Guth Brad_Guth Brad.Guth BradGuth

"Martha Adams" wrote in message
news:lJCnk.660$7N1.338@trnddc06...
"Alan Erskine" wrote in message
Again; imagining something and actually making it happen are two
different things.

===========================================

OK on the obviosity. What's the point?

Just like Mookie's 'dream'; it'll never happen. For the reasons I've
already stated.

Ian Parker wrote:

:On 10 Aug, 12:36, Fred J. McCall wrote:
: Ian Parker wrote:
:
: :On 10 Aug, 11:50, Fred J. McCall wrote:
: : Ian Parker wrote:
: :
: : :On 9 Aug, 23:35, Fred J. McCall wrote:
: : : Ian Parker wrote:
: : :
: : : :
: : : :You are assuming that heavy lift is need for SSP. In fact what you
: : : :require is the phase locking of small (a few Kw) units.
: : : :
: : :
: : : That may be what YOU require, but is anyone proposing building one
: : : that way?
: : :
: : : Why do I doubt it?
: : :
: : :
: : :Its the onlt logical way to do it. Having large parabolic mirrors at
: : :GEO is totally impractical.
: : :
: :
: : Oh, is it? *Why is that?
: :
: : While you're at it, why do you need "large parabolic mirrors at GEO"
: : for SSP?
: :
: : --
: : "Some people get lost in thought because it's such unfamiliar
: : *territory."
: : * * * * * * * * * * * * * * * * * * * --G. Behn
: :
: :There are 2 basic approaches to beaming energy. One is to have a large
: :fixed mirror. The other is a phase locked array. I am discussing phase
: :conjugation and it is very interesting. Instinct tells me that a large
: :fixed mirror cannot be the way forward.
: :
:
: True, but that is primarily because using visible light for beaming
: power is not "the way forward". *How do you propose to solve the minor
: problem with that stuff called 'cloud cover'?
:
: All this was worked out long ago. *There's no reason to change it now.
:
:
:Clould cover is a sighting problem.
:

No. If you're using visible light frequencies, cloud cover is a
TRANSMISSION problem.

:
:It all depends where you are
:beaming to. If you want to electrolyse water you simply site yourself
:where there is little clould cover.
:

Which is rather like saying that if you want to electrolyze water you
simply site yourself where there is little or no water.

:
:If again you want to power
:aircraft at 10,000m there is little clould.
:

You're not going to do that from orbit.

:
:William Mook is championing light. I am not convinced of the
:advantages over microwaves myself although we should, I think, have an
pen mind.
:

In general, if William Mook is championing something, it is probably a
good thing to stay away from. Mr Mook has a years-long reputation for
wanting undoable things done.

:
:The same arument about phase coherence occurs with
:microwaves too.
:

Solutions are already known. Use big transmitters and big rectennae
for receivers.

--
"The reasonable man adapts himself to the world; the unreasonable
man persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man."
--George Bernard Shaw