| Subject: Re: Google Earth overaly for the tall tower at Groom Lake |
| From: "miso@sushi.com" <miso@sushi.com> |
| Date: 18/02/2009, 04:48 |
| Newsgroups: alt.conspiracy.area51 |
On Feb 17, 2:10 pm, "m...@sushi.com" <m...@sushi.com> wrote:
On Feb 16, 9:29 pm, obviouslydelusional
<obviouslydelusio...@gmail.com> wrote:
On Feb 16, 12:15 pm, "m...@sushi.com" <m...@sushi.com> wrote:
On Feb 16, 10:58 am, obviouslydelusional
- Almost all unguyed towers have a diminishing cross section with
height. That is, they are narrower near the top. Their bases have to
be of greater cross section to resist the bending moment due to wind
loading and/or horizontal saucer impact. In the case of guyed towers,
the cross section can remain the same as it gets taller, as the guy
wires control the horizontal load. The Groom tower appears to have
constant cross section, but without guy wires. This is very odd. It
suggests the need for a constant internal volume.
This I totally agree with. That is, the towers getting smaller at the
top. Now if you were going to do something with radar at the altitude
of flight, you would probably want sensors at multiple heights, and
that would imply not making the tower smaller at the top.
Having "stuff" at different heights wouldn't normally result in a
cross sectional change, at least for items the mass magnitude of
sensor arrays. The main bugger is lateral wind loading, and to a
lesser extent, seismic loads. A properly engineered free-standing
tower should always taper, as that will match the loading. Now there
are a couple of reasons to deviate from that. One would be if it's
not worth the expense to construct a tapering section. Sometimes just
putting up a cheap, simple, straight pole is all you need. It's not
worth the cost of building a tapered pole. But in the case of
assembling a truss structure you ARE building it. Might as well taper
it to save material costs. The second reason not to make it tapered
is you need the internal volume fixed in order to enclose or support
something. Don't know what though.
- Some towers of relatively large cross section contain internal RF
radiators for comm purposes. These are usually referred to as self-
radiating masts. This is a possibility, but why was the tower built
with a constant cross section?
Do you mean the tower being like an AM radio type radiator? You need
to isolate the tower from the ground with ceramic insulators. Anyway,
there is usually a transmitter shack nearby.
This doesn't seem like an especially likely possibility, but can't
rule it out. How do you know the tower isn't insulated? As an
example, see figure 10 in the following document, showing the radiator
inside a tower. Seems like it shouldn't work, but apparently it does.
http://www.ramboll-telecom.com/services/~/media/Files/RT/Analysis%20a...
> - The lighter than air tether concept is intriguing. This has
been
the traditional means of docking lighter than air craft. The large
internal volume of the tower could contain equipment or personnel
lifts. Perhaps a connection with the newly constructed very large
hangar?
They have been flying a Zeplin out of KNUQ lately. It just sits out on
the ground, i.e. no new infrastructure was added.
If the craft in question has the typical elliptical shape, then your
argument makes sense. But what about non-standard lighter than air
shapes with the planform of a triangle? Or a craft with stealth or
other sensitive material that needed to be kept away from the ground?
- All that aside, have a look at this paper called, "External
Calibration of Millimeter-Wave Atmospheric Radar Systems Using Corner
Reflectors and Spheres". It may be found at:http://www.arm.gov/publications/proceedings/conf11/extended_abs/berga...
The paper describes shooting metal spheres up out of a tower via air
cannon to calibrate a weather radar system used for determining wind
shear. Note that Figure 1 in the paper shows a schematic with a
calibration corner reflector pointed at the radar system.
But that tower was fiberglass.
And you know the material of the Groom tower to be....??
Now we turn back to Groom and Google Earth. Where is the tower
located? Adjacent to the DYCOMMS RCS facility. Note that the
easterly vertex of the tower appears to be pointed directly at the BDD
(Big Damn Dish). There is some angular distortion due to the
satellite image angle, but it looks close. Finally, look at the
shadow cast by the easterly vertex of the tower on the ground. There
is something about a third or quarter way up attached to the tower
edge. Compare this to the Figure 1 schematic in the paper and
calibration corner reflector.
I see the item you mention, but it could be a dish hung on the side of
the tower.
Agreed.
As a slight divergence to the subject, have you noticed in GE what
appears to be the white, circular foundation for the tower,
presumably concrete? At least that's what the eye wants to see at
first glance. But....what if that were a rotating base instead and
the tower could be turned? Only images taken over time will reveal
any change in position.
It is known that in the past Groom has used aluminum spheres dropped
from aircraft to calibrate their RCS facility. They live on today as
boundary markers. Perhaps the tower is a "sphere cannon" to fire
calibration spheres up through the BDD's target area. This would be
much more accurate than dropping from aircraft.
What is ironic here is we are at the point where you have to wonder
how much these aircraft designers depend on RCS measurements. That is,
CAD is much more advanced than the days of the F117. You can tell this
simply by how they don't use those angular dimensions anymore. [I
suspect but have no proof that LLNL NEC program was used in stealth
design. The old version was very primitive, being computer card based.
Remember, the punch card didn't die until the early 1980s.] Anyway, my
point is RCS measurements may not be as important as they used to be
since they get it right at the design stage.
RCS testing remains still as a very big deal. Computational analysis
will get you very far these days, but it's not 100%. There are still
surprises due to interactions of assemblies. When you've thought of
and addressed every possible contingency, what bites you in the butt
is what you didn't think of. That's what testing is for.
Don't know about the NEC program. The F-117 was designed using the
Echo-1 program (per Ben Rich's book). The B-2, with the much more
advanced curved surfaces, was done with Echo-2 (or so it is rumored).
Aesthetic tower my arse. ;-) Interesting paper.
When I said program, I meant program. ;-) NEC is an old Fortran
program for antenna analysis. It is now open source. NEC2 can be run
on a PC these days, since a PC is probably like like 1960's
supercomputer, if not more powerful. Part of NEC deals with reflected
radio signals.
http://www.nec2.org/
It is a user pain in the ass, but the results are pretty good.
I'm willing to bet there is a lot less emphasis on RCS testing, but I
suppose it is hard to prove. You can tell by how dramatically the
stealth aircraft DON'T resemble the F117 that computers are involved.
The F22 is pretty stealty, but don't look all that strange.
My guess is the RCS is used in qualification of aircraft shape, not
design. That is, you prove to the feds that you met the test so you
can sell it. If you had to depend on RCS data in design, the project
would certainly take longer. Time is money. Worse yet, you take too
much time you may not get the next contract.
Two more things here. One, Lockheed wrote their own version of NEC,
called MM3D, which was rumored to be stolen by the Soviets. Second,
you would probably put a plane through RCS if you were working on
active stealth. Of course, there are arguments if active stealth even
exists.