A review of Area 51 and its tech

reply to post by mbkennel


When the do RCS, the target is rotated. So they know the cross section from all angles. I guess emitter isn't the right word. Each antenna is used for transmit and receiver. You ping and then see what is reflected. If the panels are flush with the frame, then the frame will not interfere with the antenna.

en.wikipedia.org...

This wiki leaves a lot to be desired as far as explaining phased arrays. Note my knowledge is only of the time delay type. I'm not so sure about the other phased arrays mentioned in the wiki.

en.wikipedia.org...

Not so good either, but beam forming is hard to explain. A noise cancelling microphone is a form of beam forming. You can do beam forming with RF or sound (especially sonar).

In any event, you don't need a tower for a blimp. They run a blimp at KNUQ as a tourist attraction. It goes right to the ground. If they did need a tower, why do you think it would look differently from the old blimp towers still standing?

www.airshipventures.com...

I'm not positive, but I think if they ever moored a blimp to that tower, you would see the blimp simply from the lights on base. And then they couldn't really work on the blimp if it was on a tower. That is why they had those old blimp hangars.

reply to post by gariac


Yes, of course they rotate the target, you're right, I was thinking of a full indoor anechoic chamber. But when I looked at pictures of all the other outdoor RCS ranges, they look different, and as I would expect. There is just one direction the beam*s* come out, but there are multiple antennae covering the various parts of the frequency spectrum; the physical design for antennae for the various frequencies is distinct, as are the circuit designs.

I don't see that on the tower in question.

If it were RCS I'd expect one single obvious preferred direction, instead of three apparently equal ones (what's the point when you can move the target) with only a uniform set of apparently invisible antennae.

(Yes, I think I know how beamforming works---with multiple oscillators whose relative phase you can individually program and control you can do all sorts of neat tricks in the far field)

Regarding blimps:

Of course they'd have a hangar, but there can be reasons to have a mooring post too---quick refuel, crew/cargo change, or a place to sit while they get the hangar ready, or possibly to wait until the winds are sufficiently low that it can safely fly into the hangar. In the 1920's airships had hangars and mooring posts.

It could be considered too dangerous/risky to bring the craft to ground level in ambient environment (airships are very light and sensitive to winds); a hangar landing might be tricky.

As far as the physical design, well it's generally determined by function and economics (high strength, able to support bending loads, no need to have enclosed office space) , and steel girders work the same way they did in 1920 and when they built the Eiffel tower.

reply to post by mbkennel


I have no explanation why the tower rotates nor why there are panels on all sides.

For "normal" RCS, a dish is a broadband device. The gain will vary with frequency, but basically the dish covers a wide band. The feedhorn is also wideband. Now for phased arrays, I don't believe they are as frequency agile. But radar is a narrow band device since noise is proportional to the square root of the bandwidth. Radar needs to recover weak signals. RCS, given the proximity to the target, doesn't need to be as sensitive. Eh, I'm rambling here.

So if the tower was for a blimp, why would it have panels at all?

Originally posted by gariac
reply to post by mbkennel

 

I have no explanation why the tower rotates nor why there are panels on all sides.

It may be time to Think Different.

For "normal" RCS, a dish is a broadband device. The gain will vary with frequency, but basically the dish covers a wide band. The feedhorn is also wideband. Now for phased arrays, I don't believe they are as frequency agile. But radar is a narrow band device since noise is proportional to the square root of the bandwidth. Radar needs to recover weak signals. RCS, given the proximity to the target, doesn't need to be as sensitive. Eh, I'm rambling here.

Empirical examples of known RCS ranges, say where they tested the B2, show something different. www.thehowlandcompany.com...

So if the tower was for a blimp, why would it have panels at all?

There aren't any obvious panels in the third picture in the original posting that I could see. Maybe it's an illusion or artifact of construction technique. I just see horizontal girders which may be a different color (composites? or shaped to reduce effect of cross-winds?)

They built a tower for some reason and a tower has to be high. What are the possible reasons to be high?

if it were just a radio transmitter, it would look like a radio transmitter, no need to go to the expense of building something so strong. If it had to support something on top, say like water or a air/ground-traffic-control or observation tower, then it would have to be stronger, but there isn't much of anything on top---permanently affixed that is.

There appears to be a center core, but why? Something has to go up and down inside. Why?

I can't figure out any obvious safety functionality, and it seems to be nonsensical for security observation (you'd have huts with panoramic vistas on a foothill).

Also, any tower in the middle of a *flight* *test* area must really be necessary---you usually don't want random towers just for the heck of it, and I don't think a flight test squadron includes expensive non-functional modern art.

And finally, it is pretty far away from the offices. Why? If it were just to "look out" from, why make it so far away?

I agree that blimp mooring post is a pretty exotic explanation but I can't think of any other which fits logic and observational evidence.

The Tejon ranch facility is a very conventional RCS. A bit smaller than Hellendale, but both are similar. Hellendale of course has the ability to hold the test article underground and pop it up. Anyway, I don't see why you mentioned these facilities. They are frequency agile, but they use horns and dishes, so it is easy for them to be frequency agile. I don't see how this is inconsistent with my comments on phased arrays. Incidentally, Jim Howland used my photography to show the "Dycoms" section of Groom Lake, er not that he would admit anything beyond liking the photograph. I should get him to upgrade to the July 2010 imagery, which is better than what he used.

I am not saying this is a radio tower, but rather a tower with panels in it, which to me makes me think it is some sort of phased array technology. Now that I think about it, if it was just radar rather than RCS, it would have height finding capability. A vertical phased array would be able to steer the a reasonably sharp beam in the vertical direction, and less so in the horizontal. [The array has more vertical cells than horizontal cells.] Basically to do beam forming, you need to occupy some physical space so that the panels have a natural time delay between them.

The July 2010 pano and the google earth imagery suggest to me the tower has panels. Incidentally, a conventional radio tower would be held up with guy wires. Guy wires are terrible for aircraft. They are hard to see. Building a free standing tower that is around 150ft to 180ft tall is like building a 15 to 18 story building. This is serious engineering.

Regarding the notion of testing an aircraft from multiple directions simultaneously, in engineering there is the notion of superposition. [This has nothing to do with the Kama Sutra.] If the system is linear, then you can do one "test" at a time and then combine the results to see what would happen if you did all the tests at the same time. The wiki does about as bad of an explanation as I just did.

en.wikipedia.org...

reply to post by bobw927


Checking out the dugway proving ground on google earth I found what looks just like the henge that was allegedly used to test the "nazi bell" in europe. The almost exact construction can be viewed in this video:

www.youtube.com...

I know it´s Proj Camelt** but it is still pretty interesting imo.

If you´re interested in the bell check out Joseph P Farrels books or check out this coast to coast show:

www.youtube.com...

Cheers!

reply to post by firepilot


Well to me that base still seems to be very active. The runway is brandnew. Did I miss something?

I think area 51 is just a giant red herring these days. I don't doubt that at one time it was some place very important to TPTB, but it has become to high profile recently to do any serious secret research. Granted, there could still be things going on underground, but as far as aircraft and such are concerned, I think it highly unlikely.

Also, a blimp? Really? Blimps are huge, ponderous, and slow. Not to mention an easy target to take down. The only way one could go unnoticed is if they have come up with a way to make it actually invisible, not just stealthy radar type style.

Originally posted by InvaderSkich
I think area 51 is just a giant red herring these days. I don't doubt that at one time it was some place very important to TPTB, but it has become to high profile recently to do any serious secret research. Granted, there could still be things going on underground, but as far as aircraft and such are concerned, I think it highly unlikely.

Also, a blimp? Really? Blimps are huge, ponderous, and slow. Not to mention an easy target to take down. The only way one could go unnoticed is if they have come up with a way to make it actually invisible, not just stealthy radar type style.

Well, there have been many reports of Big Black Triangles flying slowly.

It may not be fully neutral buoyancy and could use dynamic lift as well (consistent with the triangle planform)---it may not be able to hover without active engine use.

And yes, active optical stealth (intelligently illuminated ground-facing panels, possibly even engineered metamaterials) would be the key novel technology. It's not invisible, like with stealth, the actual term is Low Observability. Just a little bit away you can make things appear very odd or barely recognizable. In daylight if you illuminate the bottom with the right brightness & color blue for the altitude and dust, a craft can be very hard to see---this has been known for decades.

There's no question that passive and active optical stealth is A Big Deal.

Check out this link from 10 years ago:

forum.keypublishing.com...


The final step is Cognitive Stealth a.k.a. low recognizability. Conduct certain operations in a way to make it appear to be what people imagine an ET craft to be. This makes it less likely a, say, Revolutionary Guard commander at a SAM site will press the button if it is observed. Active illumination can help.

The tower in question looks to me like some type of solid state phased radar array a
little like RAF fylingdales but on a smaller maybe more advanced version for testing
the latest stealth tech. this is just a guess on my part based on looks and probability,
like it has 3 sides and the panels look flat but actually they have nodes all over them.


upload.wikimedia.org..." target='_blank' class='tabOff'/>

the nodes.

reply to post by stealthyaroura


The US has similar arrays (Pavepaws). I never saw a panel close up, but the element reminds me of a discone. That is another very broadband antenna. I think these phased arrays are a bit more agile than I suspected now that I have seen the individual element.

The pavepaws array is more or less circular. That gives it the ability to beam form to both the side and up/down.

reply to post by mbkennel


Thanks for the article. Interesting stuff! I have to say, I find the possibility of active stealth like that much more believable then any government having a use for blimps. Though, you could be on to something with the slow triangles being mislabeled.

reply to post by gariac


interesting.So are we still thinking radar here with the strange structure?
on a side note my uncle was a radar tech at RAF fylingdales
from the 70's through to the 80's.
USA run, with British civilians at the time.
just like Menworth hill is now. (The worlds largest listening station in the world)

Let's see. The goal of stealth is to minimize electromagnetic radiation reflections. This "active stealth" emits electromagnetic radiation known as light. ;-). This seems counterproductive.

I'm always skeptical about these active visual stealth schemes. If you think about it, the object has to match the background based on the observer's location. Hence it has to "be all" to all that see, but the observers have different viewing locations, so there is no optimal light to emit.

Then there is the issue of shooting beyond visual range. Given the reach of modern weapon systems, you will be terminated way before you see the whites of their eyes.

duplicate post, sorry.

Originally posted by gariac
Let's see. The goal of stealth is to minimize electromagnetic radiation reflections. This "active stealth" emits electromagnetic radiation known as light. ;-). This seems counterproductive.

No, the goal of stealth is to minimize observability, meaning that you want electromagnetic emissions and scattering as indistinguishable from background as possible. Background in 2cm microwave isn't the same as in optical.

I'm always skeptical about these active visual stealth schemes. If you think about it, the object has to match the background based on the observer's location. Hence it has to "be all" to all that see, but the observers have different viewing locations, so there is no optimal light to emit.

There is no optimal light to emit just as there is no optimal microwave to refract. But you know pretty well what the luminance of the sky at various altitudes and weather conditions is, and if you have decent intelligence, you know where the most probable bad-guy-shooting-at-you locations are likely to be. This isn't any different than radar. There are tow obvious directions: where the SAM site is, and if that doesn't work, in the direction of the SAM, to confuse a modern imaging targeter.

And empirically, doing just a little bit with decades old technology seemed to buy a pretty decent capability from the reports. The best is the enemy of the good. Sure, if your opposition had a full-sky real-time multispectral four meter telescope with 2 pi optics projecting onto a Keyhole-quality gigapixel CCD with 10 teraflop signal processing you'd be detectable optically at some good range. Well, you can't get those on amazon, and your opponent might not have them everywhere.

Then there is the issue of shooting beyond visual range. Given the reach of modern weapon systems, you will be terminated way before you see the whites of their eyes.

And that's why the B2 is how it is. Even the F-22 and B-2 show up, at short enough distances and high enough transmitted power, but in real application, the welcome present would have already launched. Or you would have already taken the pictures you needed.

You're limited by your worst return, so it makes sense to have broad-spectrum low observability across all sensor modalities to a given standard. You then plan your mission around that. If you can be seen at 5km, you have to do whatever you need by 7.5 km.

so what kind of telescopes or cameras do we need to get clear shot of the area?

reply to post by mbkennel


Your argument is just semantics. The aircraft is observed by radar, hence you minimize the echo in the direction of the observer.

You can't put a light on a plane and match the background. Point sources have an inverse cube fall off. The light required would be a function of the distance to the observer. But if you knew the position of the observer, you would just take out that target. A panel light source would be inverse square law, but a similar problem. And then this lighting has to stand up to the friction hence heat due to air resistance.

Basically high standoff BVR simply makes visual stealth an academic exercise. This doesn't mean the aircraft should be painted lime green, but the point is agonizing over being spotted visual isn't required these days.

The biggest threat is the accidental contrail.

reply to post by minusugune


If you are referring to getting a shot of Groom Lake from Tikaboo, you need to achieve an equivalent focal length around 2500mm with about 3 inches of aperture. That means a 5 inch reflector or a 3 inch refractor telescope, plus a barlow or eyepiece projection. The refractor will beat the reflector in a "poor seeing" condition.

If you meant seeing the planes in the sky, check out the Tonopah Test Range website. They have the visual tracking gear.

reply to post by ApplesOnFire


It's somewhat hard to tell but the towers almost looks like solar panels of some sort, and less like windows. I do agree with your comment, I also do not believe Area 51 is used for harboring aliens. I do believe however that Area 51 is used for the same things it has been known for such as experimental aircraft. I love hearing about this and hope over time more information is released to the public.