Gimbal distance and Speed Range Estimates using Lines of Bearing and/or DCS

My take... The plane is still banked left, but it's not turning anymore. That is to say, the turn was coordinated until the target was more or less front of the plane.
Being banked but not turning puts the aircraft into a sideslip.
I see no reason for the pilot to not level the wings in that situation.
 
I notice that not all information we have on this case is used.

In the analysis so far, is there anything in the Gimbal video that falsifies the report given by Ryan Graves given in a previous post, i.e., the object was within 10 nautical miles, it approached the other objects on the SA, and then came to a stop while the other objects made a 180 degrees turn.

If not, I see no added value in inventing alternative scenarios that contradict his report.

There's a difference between falsifying claims of others, like the claim of sudden moves or high speeds in the other two Navy videos, and inventing alternatives to claims made by a Navy pilot that are supported by his video evidence. Who do you think has the highest credibility in the latter case? He does not claim it was ET, he only makes claims about distance and movements that can or cannot be verified with the ATFLIR video.
 
In the analysis so far, is there anything in the Gimbal video that falsifies the report given by Ryan Graves given in a previous post, i.e., the object was within 10 nautical miles, it approached the other objects on the SA, and then came to a stop while the other objects made a 180 degrees turn.
Note that "came to a stop" is with respect to the ground; since there was a 120 knot head wind, air speed would still be 120 knots, and pulling a fighter into a steep ascent might easily do that (though I doubt 120 knots gives it the best rate of climb).

If we trust this information, we can rule out spacecraft and most commercial jet flights.
 
@Itsme

I think the 10 Nm range is consistent with the data we have. I don't know if that's the solution, but it cannot be discarded because it is one of the possible solutions. And if anything, the pilot testimony gives it more weight.

I have added a measure of the object's size at PT1 (0'01 mark) and PT4 (0'31 mark), based on the distance and FOV, using the fact that the object represent 1/23rd of the width of the screen at the beginning of the video (post #159 by @Edward Current) and is 20% bigger at the end (his post #190). This gives additional constraint to the possible trajectories, as the estimated size of the object must remains roughly similar between PT1 and PT4 (this is of course under the assumption it's not changing shape).

To match R. Graves' report, Gimbal would have to be somewhere in the 10Nm range at PT1. At 10Nm it's estimated size is ~ 6.2 m. It looks like this :

PT1.jpg

At PT4, it would be around this location :

PT2.jpg

About 10% closer from the F-18, explaining its apparent size in the ATFLIR is ~10% bigger. Measured from this point, it's corresponding size is similar, 6.2 m, so this is consistent, the object does not change size. If it's going against the wind, the West would be on the top on these plots (and at the beginning, the F-18 would also fly against the wind in fact). Gimbal is not stationary, but it moves by ~1.2Nm in 30 sec, i.e. ~150 Knots in average (270 because it's going against a 120 Knots wind?), with a stop at the end. And of course an "impossible maneuver" since it stops but keep its altitude.

The background clouds would have to be behind the intersection of the lines of sight (to go from right to left), so at least at 35-40Nm from the F-18. The cloud cover presents around the time of the event could help to know how far the clouds were, because in order to be visible in the ATFLIR that is looking -2° along the vertical, they must have a certain height. But this is much more uncertain and I don't want to speculate too much here.


CLOUDS.jpg


Again, this is one option among others, but one that would match Ryan Graves' report.
 
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Graves, from 20:25 in the video below:

This object [gimbal] was proceeding behind the larger group and essentially it approached and then it stopped for a bit and then as the formation turned back 180 degrees it just stopped from that position and then immediately went in the other direction more or less.
Content from External Source
Note that the object isn't claimed to be stopped during the video.

If it's moving, the sightlines cross on the near side.

I've mutilated TheCholla's drawing by adding a Gimbal trajectory (red line) along the last sight line (because it appeared stationary at the end) and indicated some other sight lines, if the UAP was flying straight.
PT1.jpg
 
Doing some numbers:
Given that we have the elevation angle (looking down 2 degrees), if we had the altitude or distance to the target it could be possible to calculate the other (distance or altitude). We don't have any of them, but since they are related, it is possible to at least see how one depends on the other.

beta_angle.png

where beta is the down-looking elevation angle, h1 is the F-18 altitude, h2 is the altitude of the target, d is the ground distance over an spherical earth between both, and R is the radius of the earth. I want to see how 'h2' depends on 'd'. And it looks like this:

gimbal-rangevsAltitude.png

where I deliberately made the calculation as far as 1000 km for those looking into the Atlas hypothesis.

Edit to include a shorter range version of the plot:
gimbal-rangevsAltitude2.png

1. The minimum altitude the gimbal object can have is about ~12500 feet, and the object would be at 220 km distance (122 NM)

2. At 10 NM (18 km), its altitude would be 23000 feet

3. If the altitude of the top of the clouds can be determined (check this thread), that may increase the minimum altitude the object can have, and hence the downrange could be also limited to a maximum.
 
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Unless somebody comes up with good arguments against it, I consider this is a good estimate of the situation.
I think the estimates that have been posted by myself and others with two independent methods make it fairly clear that given the uncertainties and unknowns involved the object could be pretty much anywhere and the lines of sight don't give enough information to constrain the range in a useful way.
This is of course inconsistent with a plane.
Since the object could be anywhere, it's consistent with a plane.
Finaly, a far away plane does not match the 9% growth in the size of the object,
The image does not show the object but rather a lens flare / glare produced by intense IR coming from the object. The size of the glare is a result of the convolution of the source intensity angular distribution (as seen from the detector) together with a characteristic function that describes nonidealities in the optical system. That 9% increase will be apportioned between the larger apparent angular size of the source and an increase in the size of the glare just because the source is brighter. The source could be brighter because of smaller distance, or it could also be a highly directional source which became brighter as the F-18 positioned itself behind it.

Put another way: the null hypothesis that you should be trying to refute is that there is a plane, with a relatively small portion of its area as seen from the rear covered by a jet engine, which is brighter directly from behind as the combustion chamber enters line of sight. Is that picture consistent with the observed increase in size? I think it is.
 
@markus Have you read the latter posts ? The clouds tell us the lines of sight cannot be parallel, they move the wrong way for that, and they stop which is inconsistent with a steady/straight trajectory.

The plane hypothesis is not impossible but possibilities are less, with the plane having to turn a good deal for the background movement to stop, and to be at a reasonable distance to stay in realistic speed ranges.
 
I think the estimates that have been posted by myself and others with two independent methods make it fairly clear that given the uncertainties and unknowns involved the object could be pretty much anywhere and the lines of sight don't give enough information to constrain the range in a useful way.

Since the object could be anywhere, it's consistent with a plane.

The image does not show the object but rather a lens flare / glare produced by intense IR coming from the object.
We do have additional info from Graves that the object was within 10 nautical miles. They had other sensors on the objects since they showed up on the situational awareness monitor.

And the "glare" interpretation to me is still an unfortunate but persistent confusion of thermal images of exhaust plumes with optical images of bright light sources.
 
@markus Have you read the latter posts ? The clouds tell us the lines of sight cannot be parallel,
Even if they are not parallel, that doesn't mean the intersection point can't be really far away. It just means there are clouds which are even further away. We don't know how big those clouds are, their altitude, or how fast they're moving on their own. They say very little.
they move the wrong way for that, and they stop which is inconsistent with a steady/straight trajectory.
They don't stop, they slow, but all it means is that the F-18 is now moving close to parallel with the object. There is no inconsistency.
The plane hypothesis is not impossible but possibilities are less,
There haven't been any arguments that meaningfully threaten the plane hypothesis.
 
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We do have additional info from Graves that the object was within 10 nautical miles.
We know that there was a radar return reported within 10 nautical miles. We do not have any corroboration for the hypothesis that the source of the return is the same as the object that was observed. This is important, for example, in an EW context.
They had other sensors on the objects since they showed up on the situational awareness monitor.
We don't even know there were any objects. There were, if Graves is to be believed, radar returns. That's not the same.
And the "glare" interpretation to me is still an unfortunate but persistent confusion of thermal images of exhaust plumes with optical images of bright light sources.
Calling something a confusion, unfortunate or otherwise, is not an argument. If you truly believe this cannot be a glare, you're welcome to provide the data and the argument that refutes that interpretation.
 
We know that there was a radar return reported within 10 nautical miles. We do not have any corroboration for the hypothesis that the source of the return is the same as the object that was observed. This is important, for example, in an EW context.
So how do you think they got the object in the ATFLIR FOV? They must have just randomly pointed it somewhere and got lucky?

Calling something a confusion, unfortunate or otherwise, is not an argument. If you truly believe this cannot be a glare, you're welcome to provide the data and the argument that refutes that interpretation.
I have done so on several occasions but it tends to get me in trouble: my posts are put in quarantine awaiting moderator approval as a result. I concluded this topic is too sensitive on this forum because people are already highly invested in it publicy and concinved they are right personally. So I will refrain from discussing it any further here.
 
So how do you think they got the object in the ATFLIR FOV?
One of the pilots asks the same question, before he's interrupted:
"That's not in L&S though, is it?"
"That IS in L&S, dude"
"Well but the flir's looking..."
"Look at that thing!"

What was he about to ask? Plausibly, he was about to ask how come it's in L&S when L+S isn't boxed in the ATFLIR display. If the object being targeted by the pod is not actually the L&S target the radar has designated, and the operator simply made a mistake in believing he was tracking the L&S target when he wasn't, all that range information coming from the radar is useless.
They must have just randomly pointed it somewhere and got lucky?
They presumably pointed it roughly in the general direction of one of the objects, and ended up imaging something else. For all we know, what they imaged could even be the source of the fake radar returns, only much further away. That said, "luck" is not really a good counter-argument here, because the entire reason this incident is talked about is that it looks weird. They are selected for their very weirdness, where saying or implying "they wouldn't be so lucky" tacitly assumes this is a fair sample of a typical intercept. It's not. It's entirely possible that they tried to get an image of one of the fake returns, but there happened to be an actual object behind it. All the occasions where a pilot/WSO tries to get an image of a fake return but couldn't were forgotten by history. We only remember this one, because it's weird.
I have done so on several occasions but it tends to get me in trouble: my posts are put in quarantine awaiting moderator approval as a result. I concluded this topic is too sensitive on this forum because people are already highly invested in it publicy and concinved they are right personally. So I will refrain from discussing it any further here.
That sounds a little convenient.
 
@markus you can choose to ignore the data when it doesn't align with what you want the object to be. But that's exactly what this forum is supposed to fight against isn't it?

Simply show us a recreation of the event that doesn't distort the data too much and is consistent with a plane.
 
@markus you can choose to ignore the data when it doesn't align with what you want the object to be. But that's exactly what this forum is supposed to fight against isn't it?
What data am I ignoring, exactly?
Simply show us a recreation of the event that doesn't distort the data too much and is consistent with a plane.
This has been done several times in this thread by myself and others.
 
What data am I ignoring, exactly?
1) The movement of the clouds
2) The frame analysis by CassiO that allows us to refine the line of sights :
I tried to explain it here : https://www.metabunk.org/threads/gi...lines-of-bearing-and-or-dcs.11836/post-261466

Again, a plane could fit this data, but it has to turn and it cannot be very far (for example 100 Nm that was often mentioned is impossible in terms of the speed the plane should have). Not even going into the fact that a distant plane means radar error, a completely bogus pilot report, and a mysterious plane that nobody can identify. Sorry this is too much for me.
 
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Fine if you're happy with Gimbal being a plane, but I'd like those who are not convinced by it to be able to discuss the data further. For example, @Edward Current, who has made really solid analyses so far, wanted to revisit this by considering the clouds. If he has a chance to do it I'd be interested to hear what he can come up with (no pressure of course :)).
 
1) The movement of the clouds
Here's what I said about the movement of the clouds:
Even if they are not parallel, that doesn't mean the intersection point can't be really far away. It just means there are clouds which are even further away. We don't know how big those clouds are, their altitude, or how fast they're moving on their own. They say very little.

They don't stop, they slow, but all it means is that the F-18 is now moving close to parallel with the object. There is no inconsistency.
You don't have to agree with the argument, but you can't pretend it doesn't exist. Well, I suppose you can, but then you won't be making much connection with reality.
2) The frame analysis by CassiO that allows us to refine the line of sights :
I tried to explain it here : https://www.metabunk.org/threads/gi...lines-of-bearing-and-or-dcs.11836/post-261466
As I explained in the previous, there are important uncertainties in the analysis because we lack an estimate of the size of those clouds, their altitude, how fast they're moving, and how fast the object moves with respect to them. But no matter: we can take the analysis at face value; it changes little.
Again, a plane could fit this data, but it has to turn
Where's the mathematical proof of this? Remember to include all the uncertainties and unknowns, including possible different conversions between true airspeed and calibrated airspeed, wind shear (between plane and object), object velocity, wind shear (between object and clouds), cloud feature size, cloud deck altitude, etc. You have to put all this information together and show it's not consistent with any straight-line trajectory with plausible above-stall-but-below-supersonic velocities (Supersonic, however, can't be completely disregarded since this is a military training area. And no, it's not absurd that they would misidentify one of their own planes. This is a rare event, selected because it's unusual. This can't be emphasized enough).
and it cannot be very far (for example 100 Nm that was often mentioned is impossible in terms of the speed the plane should have).
This isn't true. I went back to my model and I set the airspeed at a constant 353.7 kts, which results in an azimuth delta of 2.56 degrees in the first 20 seconds, matching XXL's cloud stitching. This airspeed is between the values obtained from two different online calculators (calculator 1 gave around 355-360, calculator 2 gave around 347-352), so it's certainly plausible. Here's the result:

image_2021-12-11_165816.png
The red line represents the distance covered by a plane traveling just as fast as the F-18 in a straight line at a distance of ~100 Nm. The object would have to be traveling fast for sure, but nothing crazy. It's not even supersonic. Moreover, it doesn't have to be at a distance of 100 Nm. That's just an extreme example. If you want the object to be traveling at most about as fast as the F-18 and to be roughly consistent with a straight line trajectory, you get that the allowable region is this:

354_los_range.png
Which easily spans some 70 nautical miles of airspace. The orange dot is the position you suggested, abandoning the straight line desideratum, which was done based on the assumption that the objects in the radar were actually the same thing that was observed in the FLIR, and that Lt. Graves' report is accurate (I'm not suggesting he's lying, but he could be misremembering the exact numbers, or they could've been subject to a game of telephone, etc). One of the problems with the "extreme physics" hypothesis is that it's completely unconstrained: nobody knows what some putative alien spacecraft would be able to do, or even want to do, so you could just as well put the orange dot about a light year away and claim it's moving 70 times faster than the speed of light. Who knows? In contrast, the fact that the plane-going-in-a-straight-line hypothesis has a huge allowable range is pretty powerful, since it means if you want the "extreme physics" hypothesis to win you have a lot of stuff to reject.

Furthermore, @MclachlanM's DCS reconstructions show how closely the behavior in the video can be matched by another F-18 at 13 Nm or so, which is well within the range you think is reasonable, well within the range of possibilities supported by your own analysis (it's borderline on mine but there's a lot of uncertainty in a DCS reconstruction done by hand so it's still broadly consistent). His posts represent a clear proof-by-construction that your early assertion that "a plane could fit this data, but it has to turn" is incorrect.
Not even going into the fact that a distant plane means radar error,
I already addressed the radar issue. We're potentially dealing with an EW situation and since we don't have and probably will never have access to the data, we have no means of verifying whether the returns are genuine; and even if they are, we know the ATFLIR wasn't necessarily tracking the target the operator thought it was tracking (because L&S isn't boxed).
a completely bogus pilot report,
Where does it have to be "completely bogus"?
and a mysterious plane that nobody can identify.
Like the Chilean navy video that stumped experts for two years and was solved within a week by members of this site?
 
Markus said:
One of the pilots asks the same question, before he's interrupted:
"That's not in L&S though, is it?"
"That IS in L&S, dude"
"Well but the flir's looking..."
"Look at that thing!"

What was he about to ask? Plausibly, he was about to ask how come it's in L&S when L+S isn't boxed in the ATFLIR display. If the object being targeted by the pod is not actually the L&S target the radar has designated, and the operator simply made a mistake in believing he was tracking the L&S target when he wasn't, all that range information coming from the radar is useless.
Of course not. In the FLIR1 video the same thing happened: The ATFLIR was first slaved to the radar target and then continued to track the object optically on its own. The WSO must have done the same here. This scenario is a lot more plausible than pointing the ATFLIR somewhere in the same direction (with a 1 degree FOV) and happening to catch something else.
We can safely trust the "within 10 nm" statement of Graves.

Actually, the first question was:
"That's not our L+S though, is it?" (listen to attached file)
 

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The ATFLIR was first slaved to the radar target and then continued to track the object optically on its own.
Say that happened. Say it was e.g. slaved first and switched to autotrack before the beginning of the video. That doesn't really change the situation much because if this was some fake target projected by an EW system (or a result of a malfunction) there would be nothing there, and by switching to the vision track he might've inadvertently targeted another object that happened to be in the frame.
The WSO must have done the same here. This scenario is a lot more plausible than pointing the ATFLIR somewhere in the same direction (with a 1 degree FOV) and happening to catch something else.
Why? Most other cases where an operator pointed the ATFLIR or any similar system at some fake target in the middle of the air, he found nothing... so we never heard of those incidents. A typical Navy pilot does some 1000 flights during training alone. Even if this is a crazy lottery ticket, the Navy buys a lot of lottery tickets.
We can safely trust the "within 10 nm" statement of Graves.
Why?
Actually, the first question was:
"That's not our L+S though, is it?" (listen to attached file)
To me it sounds like "in", and so does the response. Really the audio is too distorted to tell for certain (compare green needle/brain storm), but it doesn't matter because it means the same thing: the first guy is doubtful that this is the(ir) L+S target, and insists that something doesn't add up even after the second's confirmation.

If the scenario I proposed above is what happened (fake target initially slaved, switch to autotrack, now inadvertently targeting something else), you'd expect the fake and real object positions to diverge. So if the first guy noticed that the object on the radar and the object on the flir are on different headings, he'd be pretty certain they're not the same object. He'd ask the second ("that's not in/our L+S though is it?", phrased as if he knows what the answer is), get confused with the answer (because surely it can't be the(ir) L+S), and try to clarify further.

This scenario sounds more compelling than my initial idea, come to think of it.
 
Non of the 3 videos actually show ATFLIR RADAR slaving of any kind, any reference to slaving comes from accounts.

Slave and auto track are not exclusive settings as I understand it. You can leave your RADAR slave on and use auto track to smooth the tracking as the radar SLAVE relies on the rate of return on your RADAR. So if you have a track you can leave it on slave in case your optical track is lost and auto track will be there in case your radar track becomes aged and it also is smoother because it's tracking updates faster.

Re questions like what happens if you are SLAVED to a RADAR target than you then lose returns from it, my understanding is the track becomes aging, i.e. it gets different symbology on the SA but remains a track and is updated with predictions based on last known velocity and position. At this point you might unslave I guess.

There are a lot of question that are something we could ideally only ask a non involved F/18 ATLFLIR operator about. But this seems unlikely to happen at least until that aircraft/pod is out of service.
 
you'd expect the fake and real object positions to diverge.
Graves says something like that happened.
Article:
“The wedge formation was flying, let’s call it north, then they turned their return radius right into the other direction, which is how aircraft turn. We have to bite into the air. So they turn in the other direction and keep going. Meanwhile, the ‘Gimbal’ object that was following behind them suddenly stopped and waited for the wedge formation to pass. Then it tilted up like you can see in the clip, and that’s when my video cut out, but it just kept following the other five or six, doing like a racetrack pattern,” Graves stated, explaining what isn’t shown on the public “Gimbal” video.

He also said,

“We started locking these things up as solid returns and then slaving the FLIR to it, meaning you’re seeing an IR [infrared] source. That’s when we realized this wasn’t necessarily some type of radar malfunction. There were physical objects out there.”
Content from External Source
 
Say that happened. Say it was e.g. slaved first and switched to autotrack before the beginning of the video. That doesn't really change the situation much because if this was some fake target projected by an EW system (or a result of a malfunction) there would be nothing there, and by switching to the vision track he might've inadvertently targeted another object that happened to be in the frame.

Why? Most other cases where an operator pointed the ATFLIR or any similar system at some fake target in the middle of the air, he found nothing... so we never heard of those incidents. A typical Navy pilot does some 1000 flights during training alone. Even if this is a crazy lottery ticket, the Navy buys a lot of lottery tickets.

Why?

To me it sounds like "in", and so does the response. Really the audio is too distorted to tell for certain (compare green needle/brain storm), but it doesn't matter because it means the same thing: the first guy is doubtful that this is the(ir) L+S target, and insists that something doesn't add up even after the second's confirmation.

If the scenario I proposed above is what happened (fake target initially slaved, switch to autotrack, now inadvertently targeting something else), you'd expect the fake and real object positions to diverge. So if the first guy noticed that the object on the radar and the object on the flir are on different headings, he'd be pretty certain they're not the same object. He'd ask the second ("that's not in/our L+S though is it?", phrased as if he knows what the answer is), get confused with the answer (because surely it can't be the(ir) L+S), and try to clarify further.

This scenario sounds more compelling than my initial idea, come to think of it.
Occam's Razor: your scenario requires a fake target AND a real object, BOTH in the same direction (within 1 degree).

Mine simply requires an object with a radar return and an IR signature.

The latter is more plausible but contradicts your belief because it gives credence to the 10 nm range. So you decide to reject the simplest explanation and try to defend this with made-up statistics about the number of times the ATFLIR is pointed at a radar target but sees nothing.

We're entering confirmation bias territory again, which typically leads to an endless exchange of arguments...
Not by me in this case, I'll stick to the information provided by Graves: the object was within 10 nm when the ATFLIR recording was made. There's nothing in the video that contradicts Graves' report.
 
Occam's Razor: your scenario requires a fake target AND a real object, BOTH in the same direction (within 1 degree).
https://en.wikipedia.org/wiki/Look-elsewhere_effect

Again, we're not looking at a fair sample. If the above happened frequently we'd see lots of such videos (or, more likely, none, since then the effect would be expected and well-understood).
Mine simply requires an object with a radar return and an IR signature.
Not simply: it requires the object to stop, turn around, and do a bunch of senseless maneuvers, while presenting an IR signature strong enough to obscure it completely even from close range (since we know we're looking at the glare, not the object itself). It further requires that the object resisted identification even with the pilots having the ability to come close and take a good look at it.

I suppose something like a drone carrying a strong IR flashlight to obscure identification is possible, but you have to weigh that against the likelihood of misidentification in the face of the hundreds of thousands/millions of lottery tickets the Navy buys each year in its regular operations, and the known fact of electronic warfare in the modern battlefield.
The latter is more plausible but contradicts your belief because it gives credence to the 10 nm range.
On the contrary, it explains why that range estimate would be incorrect.
So you decide to reject the simplest explanation
The "simplest" explanation is not that there was some physics-defying object dancing around in a military training area with impunity, which was pursued by pilots who were ultimately unable to see anything more than infrared images or radar contacts.

But I'm not "rejecting" that explanation: I can't reject it any more than I can reject a magic teapot in the caverns of Ganymede (because it's utterly unconstrained). I am proposing other scenarios that explain the observations without the need to assume ancient tea parties happened under the surface of Jupiter's moons.
made-up statistics
https://en.wikipedia.org/wiki/Look-elsewhere_effect

It's a real thing and you have to account for it. Pooh-poohing a proposed explanation saying "it's unlikely" in an event selected for its unlikeliness is meaningless.

Obligatory xckd: https://xkcd.com/882/
Not by me in this case, I'll stick to the information provided by Graves: the object was within 10 nm when the ATFLIR recording was made.
Again, why can we trust Graves's information is reliable? You didn't answer that question.
There's nothing in the video that contradicts Graves' report.
That's not how this works: what we have here are several possible null hypotheses which can explain the sighting without the need to invoke advanced technology, extraterrestrial/extradimensional visitors, time travelers, etc. Anybody who advances the latter explanation had better be able to reject the former. You have the much harder job here, since all I have to do is propose scenarios that are consistent with the available evidence. Your job is to reject that claim of consistency. Saying "there's nothing in the video that contradicts Graves' report" accomplishes nothing towards that goal. Also the video doesn't include radar information so by its nature it can't contradict what Graves reported.

But back to the dialogue in the video: why would pilot 1 be convinced the object was not the(ir) L+S target? Can you continue the sentence "well the FLIR's looking..." in a way that explains his disbelief?
 
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There's nothing in the video that contradicts Graves' report.
Keep in mind that at 10 NM, the glare (not the source of the glare, which one assumes is smaller) is about 14 feet across. If it's a jet (for example), at that range the wings and fuselage (even head- or tail-on) would occupy a larger portion of the FOV than the glare, so we then have to assume that the object's self-heat blends perfectly into the IR background so as to render it invisible in the video. The addition of this extra assumption — in addition to assumptions about the object stopping and turning around —actually has Occam's razor working against the 10 NM hypothesis.
 
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The "simplest" explanation is not that there was some physics-defying object dancing around in a military training area with impunity, which was pursued by pilots who were ultimately unable to see anything more than infrared images or radar contacts.
What physics is it defying? In what part of the video is it 'dancing around'? Who has stated the pilots did not see anything more? The case is most likely still classified. It could have been an advanced drone for all we know.

Again, why can we trust Graves's information is reliable? You didn't answer that question.
OK, I owe you that one: because Graves only reports the data and avoids all speculation. His report is not affected by his beliefs, and he does not hold back, invent, or reject any data because it does not fit his beliefs. That is what makes these pilots 'trained observers', not because they are incapable of observation errors, but because they are trained to report factually and professionally. Just watch the video below.
On top of that Graves has access to more information than we do and he knows the pilots who recorded the video personally.
 
image_2021-12-11_165816.png
The red line represents the distance covered by a plane traveling just as fast as the F-18 in a straight line at a distance of ~100 Nm. The object would have to be traveling fast for sure, but nothing crazy. It's not even supersonic. Moreover, it doesn't have to be at a distance of 100 Nm. That's just an extreme example. If you want the object to be traveling at most about as fast as the F-18 and to be roughly consistent with a straight line trajectory, you get that the allowable region is this:
I see two main problems with a trajectory like the one you point:

1) you use the first 20s, but the last 14s have closer line of sights. For the plane to maintain a steady trajectory (i.e. not strongly decelerate), it has to make a sharp turn. Because for a constant speed, the segments between each line of sight have to be of same length. You can argue the line of sights are uncertain and they could be further away from each other at the end. But why would the cloud movement stop then? If the plane maintains its speed, we should still see cloud motion as the camera tracks it.

2) To me the glare hypothesis is valid if we see the jet exhaust from behind (ex : Chilean case glare). In your trajectory we see it from the side all along. Why we don't see any jet signature, and why would the size of the glare increase ?

Like I said you can find a midrange point where the plane at normal speed has time to turn in a reasonable way. But midrange distance means it's less likely to not see a jet signature, especially when seen from the side (because it has to turn).

Furthermore, @MclachlanM's DCS reconstructions show how closely the behavior in the video can be matched by another F-18 at 13 Nm or so, which is well within the range you think is reasonable, well within the range of possibilities supported by your own analysis (it's borderline on mine but there's a lot of uncertainty in a DCS reconstruction done by hand so it's still broadly consistent). His posts represent a clear proof-by-construction that your early assertion that "a plane could fit this data, but it has to turn" is incorrect.

The trajectory of this reconstruction is at odd with the cloud movements, in the DCS reconstruction background clouds would go from left to right (i.e., they would open to the right, if they were in the simulation), but they go from right to left (open to the left).

Where does it have to be "completely bogus"?

If they say it was in the 10NM range, stationary (at least at some point, or going against the wind), and it turns out it's a distant plane, that's not an accurate report to say the least.

Like the Chilean navy video that stumped experts for two years and was solved within a week by members of this site?
The glare on that one is a different animal, with the clear signature of two exhausts. If doubt they brainstormed all day for two years on this one, it's probably just the time it took to get the report out.
 
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What physics is it defying? In what part of the video is it 'dancing around'?
I thought we were dealing with Graves's description, no? I think "dancing around" is a fair description of what the wedge formation + gimbal was doing, particularly with how gimbal was said to stop in midair and double back without turning to follow the rest of the formation.
Who has stated the pilots did not see anything more?
The silence here is effectively an admission that they didn't. If they had (based e.g. on reports of the cube-in-sphere types that were seen visually), Graves would say something like "so yeah then these guys approached the object, and it was shaped like a saucer and had glowing lights around it" or whatever, but he doesn't. He never said anything about visual contact with this object. Why?
The case is most likely still classified. It could have been an advanced drone for all we know.
If it was a matter of classification, the whole thing would be classified. They wouldn't be able to discuss anything about the incident, not just the visual contact portion.
OK, I owe you that one: because Graves only reports the data and avoids all speculation.
How do you know? Maybe you are some sort of insider and can confirm that, but I can't.
His report is not affected by his beliefs, and he does not hold back, invent, or reject any data because it does not fit his beliefs.
Again, how do you know?
That is what makes these pilots 'trained observers', not because they are incapable of observation errors, but because they are trained to report factually and professionally.
The claim here seems to be that the pilots report just the facts as they observed them without adding or removing anything and without inserting their own interpretations of the data. But the fact that it was reported that the gimbal object "rotated" when we know the apparent rotation was due to glare shows that this did not occur in this case, since the pilots made the (natural and understandable) error in assuming that the shape in the image corresponded to the shape of the object itself. So at least there some extra (incorrect) information was added by the observers, training or no.
Just watch the video below.
On top of that Graves has access to more information than we do and he knows the pilots who recorded the video personally.

Interesting, I'll watch the whole thing in time. Are there any specific points in there that are particularly relevant for what's currently under discussion? I watched the part where he talks specifically about gimbal and it seemed like a (useful) summarization / clarification of points he brought up in previous interviews.
 
The claim here seems to be that the pilots report just the facts as they observed them without adding or removing anything and without inserting their own interpretations of the data. But the fact that it was reported that the gimbal object "rotated" when we know the apparent rotation was due to glare shows that this did not occur in this case, since the pilots made the (natural and understandable) error in assuming that the shape in the image corresponded to the shape of the object itself. So at least there some extra (incorrect) information was added by the observers, training or no.
"Rotating glare" is an assumption, not a certainty. I've never seen glare in ATFLIR images, only something resembling diffraction spikes (at the red arrows), even when looking straight into a jet engine or a fire. I did see people confusing the Sukhoi jet exhaust plume with glare, or using images of inferior FLIR cameras with supposed glare. But we certainly do not know the gimbal object is a rotating glare.

1628779706700~2.pngScreenshot_2021-12-13-19-20-43-369~2.jpeg
 
"Rotating glare" is an assumption, not a certainty. I've never seen glare in ATFLIR images, only something resembling diffraction spikes (at the red arrows), even when looking straight into a jet engine or a fire. I did see people confusing the Sukhoi jet exhaust plume with glare, or using images of inferior FLIR cameras with supposed glare. But we certainly do not know the gimbal object is a rotating glare.

1628779706700~2.pngScreenshot_2021-12-13-19-20-43-369~2.jpeg
I do not agree with your assertion that what we are seeing in that picture is jet exhaust, I believe you think it is from the Sukhoi's thrust vectoring but the flare is in 4 directions at once and the nozzle vectoring does not work that way, and you have never fully demonstrated that it does.
 
"Rotating glare" is an assumption, not a certainty.
It's not a certainty, but between Mick's analysis and this analysis, all evidence points to rotation that is local, not distant (it doesn't necessarily have to be rotating glare). It is an assumption to claim that the object and/or its exhaust plume coincidentally rotated in concert with the plane's bank angle and as the FLIR passed 0° left–right. So, again, Occam's razor: It's unlikely that the necessary conditions of a rotating object/exhaust plume, the object stopping/changing direction, and the object being either smaller than 14' across or the same temperature as the distant background, were all met.
 
I see two main problems with a trajectory like the one you point:

1) you use the first 20s, but the last 14s have closer line of sights.
The first 20 seconds are only used to pick the true airspeed that matches XXL's stitched image. The lines I plotted in the above are taken at 1, 11, 21, and 31 seconds. The picture looks comparable if you use 4, 14, 24, and 34.
For the plane to maintain a steady trajectory (i.e. not strongly decelerate), it has to make a sharp turn. Because for a constant speed, the segments between each line of sight have to be of same length.
This is not quite right because the F-18 is turning, and in fact its turn rate changes quite a bit as it turns. In fact, I noticed something interesting: here's what the trajectories look like if you plot only the last 4 seconds, that is, right after the object crosses over in front of the F-18's nose:

355_los_last10.png
Here's the same thing zoomed in near the F-18:
355_los_last10_detail.png
... These lines never touch. There's no intersection point. More properly, the intersection point is behind the F-18, which is inly possible if the camera is moving with the object. This means that as long as the modeled trajectory here is close to right, we can conclude the gimbal object is moving right to left from the F-18's perspective. With a straight-line trajectory, it has to be beyond the mess of intersections near the convergence point. This rules out anything closer than 30 Nm or so, minimum. In my analysis the lines only look plausible for a straight line trajectory if the object is further still. Here's one of the closest ones that could fit, at 60 Nm:
355_los_closest.png

Same caveats as before apply: this is the best reconstruction I was able to make but there's a lot we don't know as far as wind shear and the real TAS, which I'm fixing to match XXL's reconstruction (which has its own set of assumptions), I had to use smoothed frame-by-frame azimuths in lieu of the unavailable raw data, so there's a large but difficult to quantify* set of possible trajectories that can be consistent here. Some new ones: the times are now 1, 12, 13, 34 (I wanted them to cover more of the video), and I made some accuracy improvements (that don't change much in the final product, but are worth noting). That said, the 10 Nm figure seems now very difficult to make consistent with any scenario.

* Difficult to display, too: using little fans instead of straight lines as ersatz error bars it might give the impression that the errors are uncorrelated.
But why would the cloud movement stop then? If the plane maintains its speed, we should still see cloud motion as the camera tracks it.
It never really stops, it merely slows because towards the end of the turn the F-18 and the object are moving roughly in the same direction. The fact that the lines after crossing the nose (when the sight lines are tangent to the path) diverge is consistent with the little remaining cloud movement here.
2) To me the glare hypothesis is valid if we see the jet exhaust from behind (ex : Chilean case glare). In your trajectory we see it from the side all along. Why we don't see any jet signature, and why would the size of the glare increase ?
That trajectory was just an example of how it didn't have to be that fast to be at some extreme distance, even if we keep the intersection point where it was. I agree that a trajectory as you described seems more likely and seems more consistent with the total of the evidence. But a jet engine is not the only thing that could create a glare like that: reflected sunlight is also a possibility, in which case it could be reflecting off the side of a fuselage, or something, it's just the jet engine seems a better match based on prior experience.
Like I said you can find a midrange point where the plane at normal speed has time to turn in a reasonable way. But midrange distance means it's less likely to not see a jet signature, especially when seen from the side (because it has to turn).
Again, there's no reason to believe it has to turn. "Midrange" here is some good 50 Nm or so. A Super Hornet, seem from the distance I indicated above (60 Nm), would have a wingspan spanning 0.007 degrees, or 1/50th of the ATFLIR 0.35° x 0.35° field of view.
f-18_at_60nm.png
About this big.

The trajectory of this reconstruction is at odd with the cloud movements, in the DCS reconstruction background clouds would go from left to right (i.e., they would open to the right, if they were in the simulation), but they go from right to left (open to the left).
Fair enough, that trajectory also disagrees with this new analysis because the sight lines would always cross even towards the end. Still you can easily mirror his trajectory across the intersection point and obtain a similar match, but with the right cloud movement and correct sight lines post-nose.
If they say it was in the 10NM range, stationary (at least at some point, or going against the wind), and it turns out it's a distant plane, that's not an accurate report to say the least.
bogus adjective
: not genuine : COUNTERFEIT, SHAM
a bogus claim
The evidence was completely bogus.

I'm assuming here that the operators described what they saw to the best of their ability. I don't think making a perfectly honest and understandable observational mistake merits the word "bogus", especially with something so weird that we're still talking about after several years and doing detailed quantitative analyses over a period of several months. They had seconds to decide what to do, and hours to think about it before writing a report.
The glare on that one is a different animal, with the clear signature of two exhausts.
Well, four exhausts. It's a four-engine plane, though it doesn't necessarily look like it because the glares sort of blur together. It's possible this is what's happening here, especially if we're dealing with a plane with engines mounted nearer the centerline, like a business jet or a fighter.
If doubt they brainstormed all day for two years on this one, it's probably just the time it took to get the report out.
But that's the thing, people are busy. I wouldn't be surprised if we're doing much more analysis work on this (with far less data) than they ever did in the UAPTF.
 
"Rotating glare" is an assumption, not a certainty
It's not an assumption, it's a conclusion. We analyzed all the evidence and concluded that it's a glare (or some other comparable artifact) because its movement is only consistent with movement of the pod, not of an object that's free to move as it pleases.

I have an analysis I've been doing off-and-on for the past few months. I wrote a program to extract the angle of the gimbal object frame-by-frame from the foia'd GIMBAL.wmv from the Navy website. Then I take the frame-by-frame azimuth data and back out the required pitch and roll that you would use to point a two-axis system towards it, and compare the two. The ATFLIR, of course, is not a two-axis system. It has internal mirrors that are used to make the movement smoother, particularly near the center. At any rate there are things I don't understand so I refrained from posting it, but here is a preliminary plot:
rot2_el2_aoa6.png
On the left you have the red dot and a simulated trajectory at a constant distance, just to illustrate the path the object takes in the F-18's sky. On the right you have in yellow the predicted roll in yellow (assuming the angle of attack is 6 degrees as in @MclachlanM's DCS reconstruction -- this is a point of uncertainty since the AoA for a given speed and bank angle depends on the weight) vs the angle of the glare in green (both wrt the horizon). It's not a perfect match but the correlation is hard to ignore, especially because we know the ATFLIR has internal mirrors. Here's what it looks like if you lag it 1.8 seconds:
rot2_el2_aoa6_lag.png

I may not understand this completely but a correlation like this would be extremely unlikely to arise due to chance alone. As such, I'm perfectly comfortable rejecting the null hypothesis that the motion of the glare is independent from the roll axis of the pod, and I'll say without prevarication that we know this is a glare (or comparable camera artifact). Even if the object ultimately turns out to be a flying saucer, what we're seeing is the the sensor blinded by its august brightness, not the saucer itself.
. I've never seen glare in ATFLIR images,

Source: https://www.youtube.com/watch?v=K6cSoBE770Q


It's a thing that happens in optics. It's not something that can be designed out, not completely. Those jets in the beginning of the video above are vipers (F-16), so single-engine, but the glare from their engines is clearly oval-shaped, like the Gimbal.
only something resembling diffraction spikes (at the red arrows)
Those diffraction spikes are an example of what you could call a "glare", yes. A glare (or lens flare) can have just about any shape. You know those laser pointers with special caps that project various designs?
1639455793273.png
That's pretty much just a controlled form of glare. Some people, like the anonymous ATFLIR technician Mick interviewed, mention that you see similar things as the gimbal when people wipe the front of the lenses with their sleeves. The little abrasions you'd get by doing this would form an impromptu diffraction grating, which is just the sort of thing that's used to make patterns like the above. Smudges and fingerprints would have a comparable effect.
 

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I'm not impressed with the correlation, Markus. First of all, you have to add assumptions about the internal workings of the gimbal to account for the stepwise rotations of the object. Secondly, the total gimbal rotation during the 'sweep' is much larger than the total object rotation. I think the correlation is superficial and pure coincidence.

A jet produces hot exhaust gases that leave the nozzle under high pressure and will expand rapidly. The shape of this exhaust plume is something like this:

Screenshot_2021-12-11-09-30-56-185.jpeg

It will be visible in thermal images. The oval shape in your video can have many causes, like aspect ratio of the video, airflow causes by the jet's wings and tail, or the fact that these jets have double tail fins and an f16 has not..

Jets produce hot air, and hot air can be seen in thermal images. This is a simple truth. I have not seen a convincing glare in ATFLIR images, or other high quality FLIR imaging systems. On the contrary, Teledyne FLIR states the absence of glare is one of the big advantages of thermal imaging.

The diffraction spikes in the ATFLIR images are probably caused by an aperture somewhere in its optical path. They don't even remotely look like the gimbal object.

So my conclusion, based on the same evidence, differs from yours. Let's agree to disagree, then.
 
@markus
First, let me say I appreciate the detailed answers, thanks for that.

... These lines never touch. There's no intersection point. More properly, the intersection point is behind the F-18, which is inly possible if the camera is moving with the object. This means that as long as the modeled trajectory here is close to right, we can conclude the gimbal object is moving right to left from the F-18's perspective. With a straight-line trajectory, it has to be beyond the mess of intersections near the convergence point. This rules out anything closer than 30 Nm or so, minimum.
Note that Ryan Graves mentions that the object stopped before proceeding in the opposite direction (20'30 mark of the video linked above). So again his testimony aligns with the reconstruction, because if Gimbal was before the intersection point (as his statement implies), it means it was first going from left to right from the F-18 perspective, and the right to left movement you see at the very end could be the beginning of the complete change of direction he mentions. But yes of course a conventional craft could not be before the intersection point (maybe some sort of high-tech drone ?).

That said, the 10 Nm figure seems now very difficult to make consistent with any scenario.
Any scenario for a conventional craft, I agree.

But a jet engine is not the only thing that could create a glare like that: reflected sunlight is also a possibility, in which case it could be reflecting off the side of a fuselage, or something, it's just the jet engine seems a better match based on prior experience.
I have no expertise whatsoever with ATFLIR systems, so I cannot say anything about that. I'd love to see examples of a plane being seen from the side only as a reflecting glare, that would help advancing the discussion.

bogus adjective
: not genuine : COUNTERFEIT, SHAM
a bogus claim
The evidence was completely bogus.
Sorry, I'm not a native speaker and bogus was not the term I wanted to use, I didn't realize it was implying some sort of dishonesty. What I meant was "very inaccurate".
 
Jets produce hot air, and hot air can be seen in thermal images. This is a simple truth

I think this issue has come up before. The main gases in the atmosphere - nitrogen and oxygen - are very bad at absorbing or emitting infra-red radiation. That's one of the major factors in the so-called 'greenhouse effect'. So 'hot air', in the ordinary sense, does not emit much IR, and would not show up on any IR detector.

Of course a jet exhaust contains other gases, notably water vapor and carbon dioxide, which do emit IR. Whether a plume of jet exhaust shows up in an IR detector must depend partly on how much of these gases remains in the plume (and of course on its temperature). Judging by the video at #314, especially in the last few seconds when the jets on the right have turned sideways-on to the camera, the exhaust plume does not show up in 'black-hot' IR much beyond the immediate vicinity of the nozzles. They don't leave a long dark trail behind them.
 
Judging by the video at #314, especially in the last few seconds when the jets on the right have turned sideways-on to the camera, the exhaust plume does not show up in 'black-hot' IR much beyond the immediate vicinity of the nozzles. They don't leave a long dark trail behind them.
That's because the plume is 10 times thinner when viewed from the side compared to viewing it directly from the back, see figure in post 315 above. A 10x thicker layer of hot gases is much more visible.

The visibility of the plume of course also depends a lot on the thrust given by the engines.

Look at it this way: the engine nozzles have about the same temperature as the gases leaving the engine, but are much better at emitting IR. Why don't we see a glare from these nozzles when the jet is seen from the side?
 
I'm not impressed with the correlation, Markus.
Whether you're impressed is not important. What matters is how likely a correlation just as strong is to arise due to chance alone, which is to say, not very.
First of all, you have to add assumptions about the internal workings of the gimbal to account for the stepwise rotations of the object.
These are not assumptions, as they're described in patents, e.g. https://patents.google.com/patent/US9121758
As a result, compensating for aircraft pitch by rotating the roll axis may require significant power to move the large associated mass, and also is not fast (or agile) and may not be particularly accurate.
Content from External Source
Secondly, the total gimbal rotation during the 'sweep' is much larger than the total object rotation.
The graph demonstrates that it's not. The claim has been made before, and I suspect the reason is the angle of attack had been neglected. The F-18 like most fighters has a symmetric airfoil which means it's always flying pointing slightly up, just to generate enough lift to keep level. Banking results in loss of lift, so the AoA has to increase even more to keep level. Since the object is slightly below the horizon plane, larger AoA means there's a smaller angle to traverse in order to go across the zenith. I don't know what the exact AoA is, but we know it can't be zero.
I think the correlation is superficial and pure coincidence.
That's certainly a remarkable claim. The object, if moving independently,
1. Doesn't even have to rotate
2. Doesn't have to rotate by a comparable amount as that required to track the target
3. Doesn't have to rotate at the same time as that required to track the target
4. Doesn't have to make only one rotation movement

And that's only talking about the graph above, which constitutes strong evidence against the independence hypothesis, but by no means the only evidence. Your coincidence model also lacks explanations for why the rotations match image bumps within a frame or so and also the rotations of various other artifacts on the camera that are due to clouds and whose rotation match that of the gimbal object.
A jet produces hot exhaust gases that leave the nozzle under high pressure and will expand rapidly.
This video refutes that interpretation. Consider for example the change in magnification that happens around the 9 second mark:
f16_before.pngf16_after.png
On the left, the F-16s are completely obscured by the glare. On the right, the glare barely covers the engine nozzle. Exposure levels are almost the same, so they can't explain this difference.
The shape of this exhaust plume is something like this:

Screenshot_2021-12-11-09-30-56-185.jpeg
That does not match the shape in the video, which is definitely widest near the nozzle and changes little as the F-16 changes aspect, whereas this structure looks very different from the side than from the rear. If you squint you can actually make out a little bit of the exhaust plume, but it's much fainter than the glare (as expected from the fact that, as mentioned above by DavidB99, atmospheric non-greenhouse gases are transparent to IR).
I have not seen a convincing glare in ATFLIR images, or other high quality FLIR imaging systems.
I think you've been shown clear examples of glare in ATFLIR and other related systems, but "seeing" something requires also something of the viewer.
On the contrary, Teledyne FLIR states the absence of glare is one of the big advantages of thermal imaging.
Total "absence" of glare would be a physical impossibility. Whatever effects happen in visible light optics happen with infrared optics as well, simply because light is light.
The diffraction spikes in the ATFLIR images are probably caused by an aperture somewhere in its optical path. They don't even remotely look like the gimbal object.
Ok, let's put it this way: there's a clear overexposed area in both the Sukhoi video and this F-15/F-16 one, right? Imagine, for the sake of argument, moving the target away while simultaneously making the infrared light more intense so that the apparent brightness of the engine doesn't change. Carry out this correlated limit taking the target all the way to infinity.

What do you expect the image in the sensor would look like?
 
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