As noted by others, a.) it really looks like a Draken, an old Swedish supersonic jet fighter used by contractors and the National Test Pilot School for a variety of roles, and b.) nothing like this ever gets "caught out" by a satellite unless it's the result of a crash (recall the panic over an F-117 going down decades ago because it 'pancaked' in a manner that could reveal its shape).
I have had acquaintances and a grad school mentor that worked on projects out at the remote test site (among other facilities). They had very, very good situational awareness about what was overhead and when, and established & practiced procedures on sanitizing things before anything got to where it could image the site. We also have decades of lessons-learned on things like heat signatures where airplanes were parked, such that their shape could be divined even when the test article was safely ensconced in a hanger.
We also practiced (and I would assume still practice) a variety of denial & deception activities to foil all manner of collectors and confuse the opposition, from RF to visual to various MASINT measures. One example is the Wet Site at China Lake, which was covertly built to assess the RCS of various maritime platforms (most famously Sea Shadow). When Soviet birds went overhead the radar dishes were pointed in a different direction and radiating on misleading frequences. The dirt spoil and vehicle tracks from the concealed construction of the test facility's saltwater pond was hidden like the tunnels in The Great Escape. Cool stuff.
> We (HN) could be tricked, but certainly not foreign state analysts
You have a high opinion of state analysts. There have been notable failures in the last few decades, and it’s hard to believe they were all intentional failures.
> If the centerline didn't extend under the covering, I'd be sure that is what we are looking at in the enhanced photo.
Why wouldn't they paint such a detail on it? If they went to the lengths of painting the aircraft (as opposed to just covering it) then presumably they want it to be credible.
I'm no expert in this stuff but to me the shadow of the plane matches other shadows pretty well, and also the shadow off the side of the hangar is light and looks like the rib structure, rather than solid so the roof is probably not solid. That seems much harder to fake.
You can also see the roof beams over the plane. Although that kind of detail could be painted on or come through the canvass if it wasn't perfectly tight.
The shelters are mobile. It wouldn't be practical to paint the runway/taxiway lines on it, and I don't know how you'd get them to line up from different angles.
E-ink wouldn't line-up with anything without knowing there is only one observer and the coordinates of that observer. It would be better, cheaper, and simpler to have an inflatable replica of whatever it is.
The fact that there's a shadow at the top for the wall, but not on the right side tells me it's not covered with anything solid. (Compare to the shadow of the other building.)
Look at the top of the wall shadow. The canvas/whatever material isn't attached at the peak and is sagging, and you can see the shadow of the top portion of the arch above it.
I'd say they pulled the cover back to the end and it's hanging over the side.
Actually, that's probably not even be a 'wall' shadow, but just the roof covering hanging. Which would sag but otherwise look like a wall.
That's what it looks like to me from the unnatural bends and shadows in the silhouette. The photograph is Big Foot-quality, so it really doesn't matter what it was.
Not to mention these toys are usually not kept secret from adversaries, but rather from the unsuspecting public who are funding the toys. Citizens' resistance to military-industrial misadventure is the biggest enemy the Defense Department has acknowledged it has to deal with ..
> nothing like this ever gets "caught out" by a satellite unless it's the result of a crash (recall the panic over an F-117 going down decades ago because it 'pancaked' in a manner that could reveal its shape)
With the proliferation of private imaging satellites in the last decade, this might be less doable than it used to be.
Cool, but India, Korea, China, Israel, and the EU all have imaging startups. Expecting Area 51 to stay unobserved when there were a few dozen spy satellites was fine. If China launches a Starlink-style constellation what’s the plan?
Is anyone is arguing that it's unobserved? Top comment said there is situational awareness.
But in this instance, it's a US company.
They didn't get "caught out". It's an acceptable or even intentional release, rubberstamped by the overseers, likely of the NGA flavor.
And since the jet was there on multiple days, it's almost like they wanted countries with less than full satellite coverage to have time to get a peek.
I would assume stealth aircraft are rather hard to clearly image with a Synthetic-aperture radar satellite. But the point was more about cutting down on the number of satellites you need to worry about. You can’t exactly hide the fact a satellite is sending out radar for imaging.
Stealth for jets isn't primarily designed for plan view. (Referring to radar cross section isn't just a generic use of the term for "detectable area of return".)
Even if it was stealthy from above, it would be easy to identify and defeat, especially on the ground: just look for the plane-shaped area without a ground return.
Or separately, a pair of co-orbital following satellites would entirely defeat all (publicly known) radar stealth (with the transmitter offset from the receiver). The US admittedly has similar pairs of these for "scientific purposes". I assume the military/IC have access or have their own.
And synthetic aperture radar can be disguised such that its nearly indistinguishable from background noise. It's one of the features that makes it superior to old school dish radar. That's not even a secret. It's currently deployed throughout the military: ground, sea, and air. Space based platforms probably had it first.
In terms of disguising synthetic aperture radar that’s much harder with a satellite which needs to send out a strong signal to hit stuff at 300+ miles and then bounce back to another detector at 300+ miles. Especially when there is such a limited number of easily tracked satellites to be concerned with.
10x distance requires 100x the signal.
When it comes to being stealthy from above, jets bank to turn. Pilots can handle much higher g loads vertically than horizontally.
> And synthetic aperture radar can be disguised such that its nearly indistinguishable from background noise
So the transmit power is the same as background noise and you can still get useful radar pictures out of it?
Amazing. I roughly know you can recover repeating signals that are below the noise floor, but still amazing.
See: https://en.m.wikipedia.org/wiki/Spread_spectrum along with cryptographically randomized frequency hopping, you would not be able to figure out when there is an actual signal rather than noise.
Picture a point source frequency hopping different collars of visible light on your wall. There are real limits to how many photons it can send before it becomes really obvious.
As satellites need to detect returns bounced off the ground hundreds of miles away they have some hard minimums for high resolution images vs aircraft or ground stations. 10x distance needs 100x the signal.
If the surrounding area where the plane is parked is coherent (which pavement and concrete usually is) then you will see an incoherent region in the SAR imagery where the plane resides which would be quite suspicious.
You can jam it (if you know the right frequencies) and you can also passively blow it out with a big corner reflector, which tends to result in a very bright spot and loss of surrounding detail.
Tangential, sorry. In the 70s/80s I grew up ~1.5 km from a Swedish Air Force Base's runway (located in the middle of nowhere, near our tiny "city" of 5k people) equipped first with Draken and later Viggen aircraft. Our kitchen was ideal for watching takeoffs.
It was a very common thing to see a few them take off in the morning during breakfast just before going off to school. Especially Draken made such a glorious sound when taking off:
In the early 00's when on holiday, something made me look up at the clear blue sky and I saw what can best be described as a control which looked like button mushrooms laid top to bottom one after the other.
Yes, I was commenting on those. The fact that it has them and really needs them. Those things aren't optional, if you look at the take-off you can see them keep the tail safe.
The general profile of the aircraft also resembles the F-16XL, which the USAF/NASA do periodically pull out for various reasons. It has that same sort of delta profile - which is of course shared with many other aircraft.
(the F-16XL is a very interesting story and would have been an interesting airframe to explore! It's sort of like the relationship between the F-15E and the F-15, a heavier fighter-bomber airframe built on the F-16 airframe.)
The F-16XL is mostly white and is housed at Edwards (last I knew) and there are detachment people there for testing. Can't think of a good reason that F-16XL would be at Groom.
But people are over-thinking it here. There's not enough information in the photo to determine (other than the aircraft isn't white).
> There's not enough information in the photo to determine
There's enough that I can say it's not an F-16XL. The mystery aircraft is much larger - 20 meters long x 15 meters wingspan, vs the F-16XL at 16m x 10m.
> They had very, very good situational awareness about what was overhead and when, and established & practiced procedures on sanitizing things before anything got to where it could image the site.
Sure, but surely that was then and now is now.
Surely in today's world, you are increasingly fighting a loosing battle if you think you can play whack-a-mole with things passing overhead ?
With every day, week and year that passes, more and more things get launched into space by both friend and foe.
If you continue operating on the premise that you think you can hide every time a non-national satellite passes overhead then surely you are only playing a loosing game where eventually you can't get any work done because you're hiding all the time from birds overhead ?
A bit like checkmate in chess. Eventually the king is surrounded and can't go anywhere without being intercepted.
I agree, and even with the most sophisticated ways of tracking incoming overhead phenomena, worst case they'd still have only a small window of time to hide everything under the bed. And, you know, press the button that makes all the foundations flip to hide the buildings underground and reveal painted images of the desert and huge burning piles of alien corpses.
Also, it's "lose" x2 (sorry, the wrong word makes it hard to read). I'll remove this line if you could fix please.
I think that is probably true, but if they are going to get caught out it's likely to be an LEO fast moving object from Russia that they've lost track of rather than a commercial imagery platform that isn't trying to hide.
As usual when attempting perfect op-sec, this probably works 364 days of the year and then someone does the equivalent of taking a selfie with a sensitive object in the background and shares it on instagram
While the shape is somewhat similar to a draken or an f-16xl with a cranked delta wing. There doesn't appear to be a vertical stabilizer.
It's possible that this is an existing aircraft modified to test alternate aerodynamic configurations similar to the F-15 STOL. Alternately it could be a flight-ready version of one of the tailless NGAD designs.
>nothing like this ever gets "caught out" by a satellite
there is nothing secret in a 3m resolution image of a new gen fighter given that its shape looks in that resolution like any other modern aerial development platform.
The shape is exactly a Draken though. Not similar, but equal. Google images of the Draken, there's no other possible match. I think in this case the size estimates must be wrong.
Given the low resolution and thus lack of detail, it's as close to an F16 Cranked Arrow shape as it is to a Draken IMO... And the size of an F-16 and Draken are very similar, so if the size estimates are wrong, it could as easily be an F-16 XL...
> When Soviet birds went overhead the radar dishes were pointed in a different direction and radiating on misleading frequences.
That kinda assumes that there are gaps in the coverage of surveilance. That might have been practically true, but what makes it so? Couldn’t an adversary in response to such measures park their surveilance satelites in a geostat or near-geostat orbit? Or step up the number of surveilance sats such that they barelly leave any gaps?
The image you linked were made by a weather monitoring satelite. It was optimised to capture a wide are of the globe. This is clearly not the type of lens you would use to surveil military activity. It is not even the right modality to capture radar signals.
Geostationary orbit is ~36000 km above the surface. Optical surveillance satellites work at altitudes of 200-400 km and already need Hubble-like mirror sizes to achieve the needed resolution. A geostationary satellite with a similar resolution is simply not possible to build and launch in this age. Geostationary also means that half the time you're looking at darkness.
Thank you very much for the answer. (both you and all the other people)
> A geostationary satellite with a similar resolution is simply not possible to build and launch in this age.
I think I will have to read up on that specifically more. I was aware how far GEO is, but I don't understand what makes the optics impossible. (Clearly it is as you say, all the sources agree with you.) Thank you!
While we may have evolved good practices to prevent satellite based espionage, it was just last September when a TikTok video revealed some secret aircraft tech while on base.
The shadow cast by the tarp suggests it's opaque, not transparent (or even translucent, really.) Combined with the horizontal lines across "plane", it all suggests a weather-beaten opaque tarp that's been painted to conceal its contents and confuse any overhead photographers.
And there's also the fact that the other possibility seems so unlikely: why would you store a sensitive experimental aircraft under a transparent tarp? I can't think of any reason to do so.
Could be, but the shadows and taxiway lines line up perfectly. That would require constant shifting of props to maintain for 3 full days (this is 101 stuff for GEOINT folks).
It's also important to keep in mind that spy sats get far better resolution than this publicly-released image would lead you to believe.
No- there would be a solid shadow down the right side of the structure (look at the right side of the bigger hanger in the zoomed out image).
The simple explanation for the shadow is that they left the solid end (wall) of the structure up. (They're often made of a different material like aluminum, or are otherwise more difficult to disassemble due to doors or other things mounted to a semi-permanent wall.)
(ETA: If you look closely at the very top of the shadow, it appears to be a fabric/tarp wall that is sagging slightly at the peak and not attached at the very top of the arch. You can see the shadow of that portion of exposed arch/ frame pretty clearly above it.)
Having the painted-on jet shadow match the actual time of day shadow I suppose is doable if they wanted to deceive a specific satellite passing overhead at a known time, but I doubt it, since it got seen multiple times over at least 3 days.
> Agreed, from this vantage point you couldn’t tell the difference.
I mean, you could, because if it was an opaque tarp rather than “uncovered skeleton” like the article claims, it would have a solid shadow visible somewhere when the sun isn't nearly directly behind the satellite, but the “skeletal” beams would not have a shadow on the ground, because you wouldn't see the ground through the tarp.
That was my first guess. Its not like we don't mess with our adversaries. Why did I think this? Because that's what I would do if I worked there and could.
Quite a few arms control discoveries have been made by civilians using open source satellite imagery. For example, US citizens discovered the massive new missile silo complexes that China has been building. They have identified rocket motor static test burns in Iran,and preparations for missile test launches at the Novaya Zemlya test facility in Russia.
I think you meant to add 'public' in there somewhere. I'm sure the large well-funded governments were well aware of all of this stuff before the public, it's their job after all.
We came upon this development after doing our regular scans of Planet Labs' low-resolution imagery of various locales of interest across the globe… When glancing at daily 3-meter resolution images of the base
Whoa. I didn’t know that daily satellite imagery was available to civilians.
How much of the planet’s surface is imaged and available daily?
Most users (especially county assessors) of high res imaging use aircraft since it's cheaper. There are other benefits, like smaller path width and reduced angular distortion. And flying when you know there isn't cloud cover, if timing isn't critical.
So using a balloon is novel, but using aircraft in general is much more common than satellite. It just isn't all marketed to the public. "Satellite imagery" has had more success as a publicly known term than "aerial imagery", and it doesn't occur to most people that they're different things.
>Whoa. I didn’t know that daily satellite imagery was available to civilians.
There at least used to be a requirement that imaging satellite operators only release imagery up to a certain resolution, and that anything higher was subject to review/ approval (presumably from NGA). And in exchange for this cooperation, the operator gets a nice federal contract for providing NGA copies of everything imaged, plus they get their launch permit approved.
>How much of the planet’s surface is imaged and available daily?
I think Planet Labs claims full coverage every three days? But that doesn't equate to 1/3 every day, and coverage that isn't evenly distributed, due to the nature of orbital ground paths.
It's more frequent than that. From the public image spec:
> The complete PlanetScope constellation of approximately 130 satellites is able to image the entire land surface of the Earth every day (equating to a daily collection capacity of 200 million km²/day).
The US knew when <X> satellite imagery company's satellites were going to go overhead at some US base, waited for the image to be taken and then moved all its aircraft before a missile attack recently by Iran (or Iran proxies).
They know 100% who is buying what imagery, and when the satellites will be overhead.
There is 0% chance that this is a mistake. I wouldn't be surprised if the US can OK or not OK the images that make their way to Google Maps - in France, every government site gets censored before it makes its way to Google Maps.
Almost certainly a prototype for the NGAD. With rhetoric and now actions from both China and Russia the US is feeling the threat.
There is a need. The F35 is really a multi-role fighter/attack jet. F22 reportedly still reigns supreme in air to air combat, but they killed that program and it would apparently be impossible to start back up, so there is incredible pressure to have a new viable air superiority fighter.
The F22 is also a short range fighter that the US has too few of to risk losing. It is valuable for domestic defense and NATO defense, but less valuable for defending airspace in places such as Ukraine or Taiwan.
The article mentions the timing and aircraft size being right for NGAD, and take it a step further and suggest Lockheed's loud then quiet marketing of an "SR-72" might also fit. Whether re-purposed/ modified as an NGAD candidate or as a separate program.
Regardless of the NGAD program, and knowing F-22 can't reasonably be restarted, I still don't understand why we aren't developing a 2nd iteration of the f-22.
Japan's been begging for either an export version the f-22 or that they be allowed to use the technology with a new design since the beginning of the program.
A partnership could result in a cheaper, updated generation 5.5 fighter (along the lines of the F/A-18 development into the F/A-18E/F), and would result in a US ally in the western pacific (cough cough china cough) being able to natively host and support the planes.
Because it is completely pointless. It is cheaper to saturate the sky with missile trucks (human or remote driven) and play reverse Space Invaders. Also morale hit if any of "Super Fighters" would be hit would be disastrous and magnitudes worse than F-117 loss.
Same reasoning would apply moreso to NGAD. And I'm suggesting in addition to, not instead of.
A second iteration wouldn't necessarily be a "super fighter", but a cheaper, relatively conservative improvement on the existing f-22 and a hedge against NGAD delays or failures.
An updated, lower maintenance stealth coating, a slightly scaled up airframe for additional fuel and range, and an updated communications suite (that's compatible with f-35's et al)... just that would be huge. As said, an fa-18ef update.
Since the tech is 30+ years old now, it's probably to our advantage to share at least some of it with our allies. Which spreads development costs and lowers $per/jet costs.
I don't know how you envision "missile trucks" working against, eg china, but humans on-board requires missile-defeating stealth, and cheap excludes the NGAD version.
And the morale argument is what? A reason to never build an awesome fighter jet again? Cool things worthy of national pride experiencing a failure will always hit morale. But a reboot of a 30 year old jet wouldn't be the prime candidate for that, anymore than people would currently think the new fa-18 is. It's an update of what will be a ~2 generation lag behind (publicly known) cutting edge.
> relatively conservative improvement on the existing f-22
F-22 is an air superiority fighter for the Cold War. It's a nice bird, sure, but it is... obsolete?
What tasks it can do _now_ what cannot be solved by a force of F-15/18 + F-35 with a complement of UAVs? The only one what comes to mind is a deep incursions into the enemy territory... which is realistically wouldn't be needed, because the only two countries what could require such operations by the time of such operations would required would already end the war or end the war by a nuclear fire.
> working against, eg china
Exactly like it's described. Bait at the front, trucks at 50-150km behind, local C2 and data aggregation in F-35s spread behind the front.
The difference between fighting a ragtags with AKs and a country with a sophisticated AA system is what you WANT to provoke AA so it would disclose its position and so you could react to it. Also it means you /will have/ a big amount of losses and of course you would prefer to lose UAVs or at most the type you have 3x in the inventory.
> A reason to never build an awesome fighter jet again?
Why not? Build it. But never let it fly where it can be actually shot down.
Agreed. If this was discovered in one of the thousands of other air bases that people know nothing about, maybe it was an accident. With Area 51 the US knows that it's constantly under watch by parties worldwide. I'm skeptical they'd choose to do anything actual secretive there anymore.
It's a test facility. They have to take the aircraft out from overhead cover in order to actually test them. Testing only at night would be much too restrictive.
They track all observation satellites and meticulously schedule aircraft movements for when they're not observed. The problem is Planet Labs alone has over 200 satellites, and that's in addition to other commercial imaging providers and all the governmental earth observation satellites. That means in recent years the margin for error has become increasingly smaller.
Given all that, while it's certainly possible this was deliberate, I don't think it at all implausible for it to be accidental. Some occurrence that delayed them by just a few minutes could potentially have caused this.
It was left out for multiple days. This isn't some accidental misjudgment of the time. This was either placed there knowingly or put there and forgotten about for days on end. The former seems way more probable than the latter.
> That means in recent years the margin for error has become increasingly smaller.
I'm surprised that there are still windows of time where any piece of land isn't "seen" by satellite. I thought there was 24/7 coverage especially on special sites like Area 51.
>All that being said, we must underscore that spotting a totally new and exotic aircraft design in the open at Area 51 is largely unprecedented, and for very good reason.
Why even still use that base except to troll enthusiasts?
At this point, people could have been born anew, grown up with the lore, had a full career and achieved decision making roles in using those bases with no budget oversight whatsoever.
I assume because it's still a great position for a base (wide stretch of easily defendable flat land) and the infrastructure is already there.
Plus, anyone capable of seriously surveilling such a well-positioned base will most likely also be aware of any other "secret" base that's usable for launching stealth aircraft; the space requirements alone make those hard to hide.
Because there are still needs to test secretive aircraft and technology? Just because everyone knows about its general location doesn't mean everything that happens within its borders is known. There's most likely useful work being done there today.
We would occasionally pull stunts like this for adversary satellites in the old days. I've never seen a transparent scoot-n-hide, though. And if we had an aircraft break down, we have equipment on base that could move it to a hangar in pretty much any condition -- even crashed.
We were always really sensitive to adversary satellite schedules and this would not happen for 5 minutes, let alone a few days.
My hunch is that the transparent scoot-n-hide is a custom job, the aircraft is real, and this was a show for some adversary.
As for what type of aircraft it is? Can't really tell. I could see it being anything from an F-16XL to NGAD to flat pieces of painted plywood cut out into shapes (it's been done before).
Potential reason: the skin uses Radar-Absorbent Material, which is sensitive to weather and sun. Or they actually have people working on it and they don't want too cook in the sun and aircraft wind/dust/Foreign Object Damage (FOD). Who knows.
This reminds me of how they hid the U2 from prying eyes in "Skunk Works: A Personal Memoir of My Years of Lockheed" by Ben Rich, that I'm currently reading. For anyone who's interested in experimental aircraft, the secrecy and the engineering this is a great read. He talks about the lengths they went to hiding the U2 and the Stealth Fighter from surveillance and everyone else.
Can someone explain how those planes work, without a rudder or a vertical stabilizer?
The Chinese aircraft depicted in the article has large vertical surfaces on the wing tips, but other prototypes depicted in the same article have no vertical control surfaces whatsoever.
I don't understand how you achieve controlled flight without those. Am I being dense?
Edit: specifically I don't understand how do you control yaw.
The B-2 uses airbrakes at the wingtips. Actuate the right airbrake to yaw right, etc. You can also use differential throttle of two engines to achieve the same thing.
I meant more left/right thrust to control yaw without sacrificing your stealthy edges, not necessarily the full f-22 capabilities. Ie, not needing to actuate control surfaces on the wings (or minimize the need), in the context of not having a vertical stabilizer.
Iirc, the B-2 has to "hide" certain control surfaces momentarily when getting pulsed with radar.
This has been a reality since Sputnik, it's not really a recent concern. The obvious solutions are:
- Test at night
- Test with clouds overhead
- Test indoors
Once the aircraft takes off or lands hiding it is easy. It's just for the few minutes that it's out on a tarmac that you have to worry about it being spotted.
One possibility is that this is a deliberate misdirection, there is no plane in that hangar or if there is it looks completely different from the one in the picture. The fact that so many people in this thread are going down the NGAD rabbit hole (a program which is barely fleshed out and nearly all of it is open for interpretation) may indicate that this is the path the US wants Chinese and Russian researchers to go towards in order to cover up the "true" path. I'm more willing to believe that than the possibility that they left a billion dollar aircraft out in the open with a publicly tracked satellite directly overhead. It's not like they don't know when Planet or other satellites are going to be photographing the base.
One aircraft that I have always assumed existed was the SR-71 replacement. When they retired it the official story was that it was superceded by satellites, but satellites have a level of predictability and trackability that is best complemented by an aircraft. I have always assumed that they had a replacement with capabilities that were once again classified.
That said, I don't think you'd find it at Area 51 given the fact that it would have been in service for a while by now and that Area 51 is more about testing experimental aircraft.
Only if your imaging satellite had X-ray vision. Have a look again. You wouldn't put a no-roof shelter over a plane, and you wouldn't be able to see what's inside. Use common sense.
So far I've not seen any comments that consider the wider context of the location in speculating what the aircraft may be.
Specifically, this aircraft is on the D1 taxi-way of the isolated EXTREMELY tall hanger 25 (H25) [2] at the south end of the runways, away from almost all other facilities.
Hanger 25 and the E1/D1 taxi-ways connecting it can be fully appreciated in aerial photographs [3] looking north published by dreamlandresort (DR). The hanger has direct links to both runways - the primary 14/32 (via taxi-way E1) and the short secondary (unmarked) 12/30 that only serves category A or B aircraft (via taxi-way D1).
Back in 2014 as hanger 25 was being constructed there were ground and aerial photographs that revealed the hanger's large size and especially its height which could accommodate a Boeing 747 tail rudder. There was much speculation [4] that it may support a project that has a mothership with 'parasite' aircraft attached.
It may be what we're seeing in this new imagery from Planet Labs is a 'parasite' flying-wing aircraft.
It's possible, based on remote location on the airfield, that this facility is supporting an ultra-high altitude or space launch system (think Virgin Galactic style). Mothership carries the parasite aircraft to a high altitude (taking off from runway 14/32) before it is released to climb to a higher altitude or possibly into very low earth orbit (100km+ altitude).
Note: structure references from page 5 of the Jeppesen HOMEY/KXTA airfield/airspace charts [0] published at dreamlandresort (DR) [1]
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I have had acquaintances and a grad school mentor that worked on projects out at the remote test site (among other facilities). They had very, very good situational awareness about what was overhead and when, and established & practiced procedures on sanitizing things before anything got to where it could image the site. We also have decades of lessons-learned on things like heat signatures where airplanes were parked, such that their shape could be divined even when the test article was safely ensconced in a hanger.
We also practiced (and I would assume still practice) a variety of denial & deception activities to foil all manner of collectors and confuse the opposition, from RF to visual to various MASINT measures. One example is the Wet Site at China Lake, which was covertly built to assess the RCS of various maritime platforms (most famously Sea Shadow). When Soviet birds went overhead the radar dishes were pointed in a different direction and radiating on misleading frequences. The dirt spoil and vehicle tracks from the concealed construction of the test facility's saltwater pond was hidden like the tunnels in The Great Escape. Cool stuff.