FLIR Technician Discusses Navy videos and claims to refute Mick's claims

Very well put. I did posit somewhere in another thread, that the bumps could be caused by good old turbulence. Haven’t heard anyone else mention this but it seems, at least plausible to me.
The Navy fighter and the UAP are flying too far apart for the same turbulence to be causing both the camera bump and a genuine UAP rotation at the exact same time. So if you want to include the possibility of turbulence having an effect, you could replace "onboard" with "nearby" in my chain of logic, and it would still lead you to the same conclusion.
 
The Navy fighter and the UAP are flying too far apart for the same turbulence to be causing both the camera bump and a genuine UAP rotation at the exact same time. So if you want to include the possibility of turbulence having an effect, you could replace "onboard" with "nearby" in my chain of logic, and it would still lead you to the same conclusion.

The bump affects the entire image (clouds, UAP, sky) in perfect synchrony. So if indeed the bump is caused by the turbulence, the turbulence affects, at those precise moments, the Navy plane alone which is carrying the sensor system generating the footage. Your term "onboard" is therefore remarkably more apt and plausible than "nearby". The corrective rotation perfectly synchronizing with the bumps is therefore also only "onboard".
 
Perhaps I am the only one who can not see any extraordinary there. I see bumps, I see rotations. Both on a video with a very short length. It is a little piece of sample so it could be easily a coincidence.

Edit: Btw, I have the impression, that the bumps and rotations become stronger, when the object seemingly slows down. Which can be a coincidence as well. Is that aspect already discussed? The Slow down? Is there a Slow down?
 
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Perhaps I am the only one who can not see any extraordinary there. I see bumps, I see rotations. Both on a video with a very short length. It is a little piece of sample so it could be easily a coincidence.

Also, at least some of the bumps or rotations seem suspiciously very aligned with the bank angle of the airplane. How or why that would be related I cannot know, but not something I can easily dismiss.
 
Perhaps I am the only one who can not see any extraordinary there. I see bumps, I see rotations. Both on a video with a very short length. It is a little piece of sample so it could be easily a coincidence.

Easily, you say?

Then let's calculate the probability of a coincidence, assuming the 34 second GIMBAL video has only 4 rotations of the UAP (as it does), but at random points throughout any 1,25 second period in the video (which is the average length of the 4 rotations of 1+0,5+3+0,5 seconds making up altogether 5 seconds). Let's not even consider that each rotation followed each bump consistently within 0,2 seconds, which would reduce the probability of accurate synchronicity with the bumps somewhat. And yet, under this generous and simplistic model, the likelihood that one rotation would roughly coincide with one of the bumps is 3,6 %. Feel free to calculate, using a more sophisticated uniform distribution (discrete) model fit for purpose, the likelihood of all the 4 rotations coinciding with all the 4 bumps with a consistent 0,2 second delay.

The synchronicity of the rotations with the bumps is not a coincidence.
 
To make this logic more explicit:

1) It is impossible that the faraway object is bumping the camera.
2) Therefore, the camera bumps are caused by a mechanism onboard the Navy jet. [ It has been theorized out elsewhere that fine tracking is done with movable mirrors, and the gimbal system activates when the mirror system exceeds a specific window.]
3) All UAP outline rotations are synchronous with camera bumps.
4) Therefore, it's very improbable that they don't have a common cause. [They have a common cause.]
5) Because 2) posits that the cause for the bumps is onboard the Navy jet, 4) implies that the cause for the UAP outline rotation is also onboard.

6) Therefore, the perceived rotation of the UAP in the GIMBAL video reflects a property of the observer (the Navy jet), and not a property of the observed object (the UAP).

7) There is no other property of the UAP in the GIMBAL video that makes it extraordinary.
8) By Occam's razor, that UAP is ordinary.
Yeah, well-argued. And I probably should have been noting the camera bumps in my videos.
 
I agree the bumps are significant. But the reason I mentioned turbulence is because there is a definite, significant bump at start of video, in white hot mode, that does not correlate in any way with the rotation, which starts later in video. What is this bump ?
 
I agree the bumps are significant. But the reason I mentioned turbulence is because there is a definite, significant bump at start of video, in white hot mode, that does not correlate in any way with the rotation, which starts later in video. What is this bump ?
Maybe you can pin-point a bit more where it happens. It is better for the context of this thread I think. Maybe a small extracted gif?
 
It’s at the start ( approx 0:02 )- immediately before the voiceover says ‘ dude is that a f’ing drone, bro ‘. There’s a distinct bump.

Thanks. Indeed, that full frame bump motion does not look correlated to any rotation.
 
It’s at the start ( approx 0:02 )- immediately before the voiceover says ‘ dude is that a f’ing drone, bro ‘. There’s a distinct bump.

Source: https://youtu.be/QKHg-vnTFsM


Look carefully at the clouds as the bump happens. There's a small but clear change in their behaviour-- they seem to drop and rotate slightly while changing the rate at which they are moving. It's very subtle but it's there.

bump.gif

EDIT: It might be interesting to understand why, in this case, the background seems to rotate while the 'object' doesn't. IMO that's more support for the idea that the object is an optical artifact.
 
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Look carefully at the clouds as the bump happens. There's a small but clear change in their behaviour-- they seem to drop and rotate slightly while changing the rate at which they are moving. It's very subtle but it's there.

bump.gif

EDIT: It might be interesting to understand why, in this case, the background seems to rotate while the 'object' doesn't. IMO that's more support for the idea that the object is an optical artifact.
That’s my point. I took this to be turbulence affecting the pod therefore, with regards the bumps later on, I had also attributed them to turbulence. Though they do line up with the mechanical rotations of the object. If it is the pod that is creating rotating glare and bouncing around whilst it does it - it’s a pretty catastrophic failure! :) More Fisher Price than Raytheon ! Maybe we can get a Fisher Price engineer on here to counter Dave Falch !
 
"If it is the pod that is creating rotating glare and bouncing around whilst it does it - it’s a pretty catastrophic failure!"

I don't follow, the pod has limits it's a machine most of it's job is for A/G targeting and laser guidance of munitions. This is not a catastrophic failure a few slight bumps here and there under optical tracking is not an issue in the pods main job. Given the internal name of the video it's likely we are seeing a lesson in the pods limitations under certain conditions.
 
That’s my point. I took this to be turbulence affecting the pod therefore, with regards the bumps later on, I had also attributed them to turbulence. Though they do line up with the mechanical rotations of the object. If it is the pod that is creating rotating glare and bouncing around whilst it does it - it’s a pretty catastrophic failure! :) More Fisher Price than Raytheon ! Maybe we can get a Fisher Price engineer on here to counter Dave Falch !
If I understand you correctly, that almost does not matter in terms of understanding that the UFO is not doing anything extraordinary, the "rotations" are all happening at the plane/pod rather than at the UFO.
 
"If it is the pod that is creating rotating glare and bouncing around whilst it does it - it’s a pretty catastrophic failure!"

I don't follow, the pod has limits it's a machine most of it's job is for A/G targeting and laser guidance of munitions. This is not a catastrophic failure a few slight bumps here and there under optical tracking is not an issue in the pods main job. Given the internal name of the video it's likely we are seeing a lesson in the pods limitations under certain conditions.
The sensor has limitations too. Just look at the small number of pixels and low dynamic range.
 
Look carefully at the clouds as the bump happens. There's a small but clear change in their behaviour-- they seem to drop and rotate slightly while changing the rate at which they are moving. It's very subtle but it's there.

bump.gif

EDIT: It might be interesting to understand why, in this case, the background seems to rotate while the 'object' doesn't. IMO that's more support for the idea that the object is an optical artifact.

Indeed. In fact, the behaviour of the image is identical to the behaviour during the four bumps at the end of the video, since in all 5 cases the background rotates independently from the object. In this case it would simply seem the de-rotator fails to stabilize the horizon during the automatic corrective response of the camera to the bump. That's why it looks as if the background is rotating instead of the object. (Check Mick's response to Falch video.)

This bump is also much softer than the four bumps at the end of the video. This fact possibly plays into the de-rotator not engaging. Maybe it's less sensitive to bumps.
 
"If it is the pod that is creating rotating glare and bouncing around whilst it does it - it’s a pretty catastrophic failure!"

I don't follow, the pod has limits it's a machine most of it's job is for A/G targeting and laser guidance of munitions. This is not a catastrophic failure a few slight bumps here and there under optical tracking is not an issue in the pods main job. Given the internal name of the video it's likely we are seeing a lesson in the pods limitations under certain conditions.
Catastrophic was used in jest….partly….These multi million systems are designed to track, lock and follow any aircraft pulling G and all manner of evasive manoeuvres. I would think that a gentle motion from left to right should not have the pod rotating in such a stuttered mechanical manner. It looks like the wizzo is hand cranking it with something akin to an old manual car window handle. Neither the sukhoi/f18 or air to ground footage from earlier in this thread show such mechanical rotations. I’m guessing it’s not normal. The flir1 footage has a bump but that seems to be a momentary lock issue. The go fast, which I believe must have involved a lot of pod rotation to keep track is very smooth in comparison.
 
These multi million systems are designed to track, lock and follow any aircraft pulling G and all manner of evasive manoeuvres. I would think that a gentle motion from left to right should not have the pod rotating in such a stuttered mechanical manner.
Mechanical systems always have to contend with the fact that static friction is higher than dynamic friction, i.e. it takes more force to get a mechanism going than it needs to keep it moving; and that means every mechanical system will see a "jerk" if you move it from a rest position.

On a telephoto camera setup, this jerk is amplified because a small angular change looks very big in the picture. The fact that the system can start and stop and only shake by a few pixels indicates high-quality mechanical engineering.

"Tracking, locking and following" evading aircraft is a use case where a) the pod is rarely at rest, and b) the magnification is not as great, so there'll be fewer jerks, and they'll show up less. So your own objection contains clues as to why we're not seeing these bumps in other footage.
 
The sensor has limitations too. Just look at the small number of pixels and low dynamic range.
It has pretty high dynamic range, and the IR resolution is diffraction limited, so more pixels wouldn't improve it. Interlaced scan was the bigger limitation.
 
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Catastrophic was used in jest….partly….These multi million systems are designed to track, lock and follow any aircraft pulling G and all manner of evasive manoeuvres. I would think that a gentle motion from left to right should not have the pod rotating in such a stuttered mechanical manner. It looks like the wizzo is hand cranking it with something akin to an old manual car window handle. Neither the sukhoi/f18 or air to ground footage from earlier in this thread show such mechanical rotations. I’m guessing it’s not normal. The flir1 footage has a bump but that seems to be a momentary lock issue. The go fast, which I believe must have involved a lot of pod rotation to keep track is very smooth in comparison.
ATFLIR was designed for ground targeting, not dogfighting. Now, if the ownship is pulling G's, that'll make it vibrate, which is why they added Electronic Image Stabilization for the TV mode.
 
Mechanical systems always have to contend with the fact that static friction is higher than dynamic friction, i.e. it takes more force to get a mechanism going than it needs to keep it moving; and that means every mechanical system will see a "jerk" if you move it from a rest position.

On a telephoto camera setup, this jerk is amplified because a small angular change looks very big in the picture. The fact that the system can start and stop and only shake by a few pixels indicates high-quality mechanical engineering.

"Tracking, locking and following" evading aircraft is a use case where a) the pod is rarely at rest, and b) the magnification is not as great, so there'll be fewer jerks, and they'll show up less. So your own objection contains clues as to why we're not seeing these bumps in other footage.
I believe the pod is never at rest whilst in use. The ‘limitations’ of the 2 axis of movement require constant rotation when in use. If you observe any ‘ live ‘ tracking pod footage which shows the onboard screen, you can see the corners of the screen in constant rotation. All other evidence of glare back this up. The glare is constantly on the move. I’ve tested this at home to observe mechanically what a gimbal pod must do to track an object. I agree that telephoto setup shows a jerk when moving from a static position but I don’t believe such evident ‘ play ‘ exists on these gimbal pods. It’s rotating on a kind of track which by its nature cannot allow such pronounced movement. That’s why I thought it may be turbulence as something that jerks the entire pod could make this jerk. Or a failure of the pod.
 
ATFLIR was designed for ground targeting, not dogfighting. Now, if the ownship is pulling G's, that'll make it vibrate, which is why they added Electronic Image Stabilization for the TV mode.
Was atflir specifically designed for air to ground ? I feel it’s more a collection of sensors and technology to assist both forms. The manoeuvrability requirements to track an evasive air target pulling G far outstrip that required for a ground target. I would presume ( always a bad idea ) that it has a lot of on board tech specifically for air to air. The bumps do seem significant though. It’s not immediately obvious on other comparable footage.
 
I believe the pod is never at rest whilst in use. The ‘limitations’ of the 2 axis of movement require constant rotation when in use.
Except there are 4 axes.
This has been discussed on metabunk before, up to the point where Mick quoted a Raytheon patent in this thread https://www.metabunk.org/threads/gimbal-lock-and-derotation-in-flir-atflir-systems.10792/
Ideally, a high resolution imaging and laser designation system in a highly dynamic disturbance environment would typically have, at least, a four gimbal set, with two outer coarse gimbals attenuating most of the platform and aerodynamic loads and the two inner most, flexure suspended gimbals providing fine stabilization
Content from External Source
 
I feel it’s more a collection of sensors and technology to assist both forms.
The way to go when putting up a solid argument is to find authoritative sources and evidence to support opinions and "feels", especially when contradicting others. In this case, Raytheon themselves serve:
Article:
Raytheon's Advanced Targeting Forward Looking Infrared pod delivers pinpoint accuracy and reliability for air-to-air and air-to-ground mission support.
 
Was atflir specifically designed for air to ground ? I feel it’s more a collection of sensors and technology to assist both forms. The manoeuvrability requirements to track an evasive air target pulling G far outstrip that required for a ground target. I would presume ( always a bad idea ) that it has a lot of on board tech specifically for air to air. The bumps do seem significant though. It’s not immediately obvious on other comparable footage.

My impression is I don't think it was specifically designed to for A/G only, but that is a large part of its use, it's main A/A use is for visual ID of aircraft when the rules of engagement require it, it doesn't seem to be used really for tracking a target during dogfighting (a rare event in A/A combat these days) Like it cant see behind or directly above the aircraft.

You essentially give it a look to make sure it's really a hostile fighter jet before loosing a missile, how this works with very long range missile launches way beyond visual range stuff I don't know I guess the difference is "all out war" versus the kind of limited engagements that are more common these days like US intervention in Syria etc where there's busy air with allies and civilian traffic.

In A/G mode you use it to put the targeting laser on the right spot on the ground for your laser guided munitions, so it has a more direct combat role.

Reading the DCS forums about it there's a lot people on there that seem to have insider knowledge about it, unsourced but it makes me wonder where they are in the discussions they certainly are aware of the 3 Navy videos and in fact use them to point out issues with the DCS simulated ATFLIR.
 
Was atflir specifically designed for air to ground ? I feel it’s more a collection of sensors and technology to assist both forms. The manoeuvrability requirements to track an evasive air target pulling G far outstrip that required for a ground target. I would presume ( always a bad idea ) that it has a lot of on board tech specifically for air to air. The bumps do seem significant though. It’s not immediately obvious on other comparable footage.
Have you seen where it's mounted? It can barely look up and to the right.

It needs to compensate for the ownship's maneuvers, and those tiny bumps are nothing compared to real jitter.
 
Except there are 4 axes.
This has been discussed on metabunk before, up to the point where Mick quoted a Raytheon patent in this thread https://www.metabunk.org/threads/gimbal-lock-and-derotation-in-flir-atflir-systems.10792/
Ideally, a high resolution imaging and laser designation system in a highly dynamic disturbance environment would typically have, at least, a four gimbal set, with two outer coarse gimbals attenuating most of the platform and aerodynamic loads and the two inner most, flexure suspended gimbals providing fine stabilization
Content from External Source
Thanks Mendel. I am aware of this. The two axis I speak of are the rotate and pivot. I’m speaking of the combination of available mechanical movements the pod uses rather than the actual number of distinct manoeuvrable sections within the pod. To track a target 54 deg left, swinging around the front, the pod must rotate and pivot. All manner of coelostat mirrors are doing their own rotation internally , I’m sure, but it’s that fundamental foundational movement I was alluding to when describing its necessity of constant movement.
 
The way to go when putting up a solid argument is to find authoritative sources and evidence to support opinions and "feels", especially when contradicting others. In this case, Raytheon themselves serve:
Article:
Raytheon's Advanced Targeting Forward Looking Infrared pod delivers pinpoint accuracy and reliability for air-to-air and air-to-ground mission support.
It was my opinion that the atflir could best be described as a collection of sensors onboard for A/A and A/G rather than designed specifically for A/G. I didn’t feel it necessary to provide evidence but thank you for doing it for me.
 
Have you seen where it's mounted? It can barely look up and to the right.

It needs to compensate for the ownship's maneuvers, and those tiny bumps are nothing compared to real jitter.
True. I’m not looking for an argument as to what atflirs best use is. I was merely noting that there is a lot of equipment on board specifically for A/A rather than such a use was an afterthought and added on later. Also most engagements are miles away so it’s proximity to the underwing though restrictive, is less so at those distances. Pilots would have to manoeuvre with its position in mind though. Looks like 1 o’clock to maybe 5 o’clock would be a bit of a blind spot but if pointed directly at target it would be fine. A/A systems would be used to shoot a rival out of the sky long before they would become visible to the pilot.
 
Have you seen where it's mounted? It can barely look up and to the right.

It needs to compensate for the ownship's maneuvers, and those tiny bumps are nothing compared to real jitter.
I am sorry, but I am sure the ATFLIR is not only made for looking down. I cannot prove my statement though (no specification docs online of course), but perhaps you have some links or docs showing your point?
 
I am sorry, but I am sure the ATFLIR is not only made for looking down. I cannot prove my statement though (no specification docs online of course), but perhaps you have some links or docs showing your point?
A picture of it with the airframe in the way of full 360 degree view is not evidence enough for you?
 
Thanks Mendel. I am aware of this. The two axis I speak of are the rotate and pivot. I’m speaking of the combination of available mechanical movements the pod uses rather than the actual number of distinct manoeuvrable sections within the pod. To track a target 54 deg left, swinging around the front, the pod must rotate and pivot. All manner of coelostat mirrors are doing their own rotation internally , I’m sure, but it’s that fundamental foundational movement I was alluding to when describing its necessity of constant movement.
The point is, though, that to track a slow-moving target, the pod has a choice of using the outer, coarse gimbals, or the inner, fine gimbals or mirrors.

A sensible algorithm would use the outer gimbals to bring the target with a fine positioning window and then use the fine gimbals/mirrors to track it inside that window, and during that the outer gimbals would not move.

So an object moving slowly across the ATFLIR's vision would
a) initially be acquired by the outer gimbals,
b) then tracked by the inner gimbals/mirrors to a set offset from the center,
c) re-centered via the outer gimbals,
d) tracked across by the inner gimbals/mirrors to the set offset,
and so forth.

The fact that the inner gimbals/mirrors exist means that the outer, coarse gimbals does NOT need to move continuously when tracking an object that exhibits "gentle motion" across the field of view.
 
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It was my opinion
I understood that.

The thing is that the exchange of opinions rarely progresses Metabunk discussions and almost never resolves differences of opinion.
That's why I highly suggest adding evidence to your opinions, instead of leaving that to others -- especially when you know that there is a difference of opinion.

I, for one, will rarely learn from other people's opinions; I learn from evidence; and if I have to seek it out myself, chances are I may not do it, and instead go on distrusting that opinion and not learn anything.
 
A picture of it with the airframe in the way of full 360 degree view is not evidence enough for you?
I looked at an article about a comparison of the Mig-29 vs the F/A 18 the other day, and it said that the Mig-29 had an advantage because it could fire its missiles at other fighters while the targets were 90° off to the side, and the F/A 18 could not. So your implied reasoning of "if it can't target 360°, it's not suitable for dogfighting" seems flawed to me.

What we're really trying to answer is how close and how agile of a target the ATFLIR has been designed to be able to track (after it has been established that ATFLIR was designed partially for air-to-air); but I'm a bit at a loss to see why this is important for the topic at hand, maybe someone can remind me?
 
The point is, though, that to track a slow-moving target, the pod has a choice of using the outer, coarse gimbals, or the inner, fine gimbals or mirrors.

A sensible algorithm would use the outer gimbals to bring the target with a fine positioning window and then use the fine gimbals/mirrors to track it inside that window, and during that the outer gimbals would not move.

So an object moving slowly across the ATFLIR's vision would
a) initially be acquired by the outer gimbal,
b) then tracked by the inner gimbal/mirror to a set offset from the center,
c) re-centered via the outer gimbal,
d) tracked across by the inner gimbal/mirror to the set offset,
and so forth.

The fact that the inner gimbal/mirror exists means that the outer, coarse gimbal does NOT need to move continuously when tracking an object that exhibits "gentle motion" across the field of view.
I kind of agree with all your points from a) to d) there Mendel.
Though I think I disagree with what that means in reality.
I imagine ( again, no expert ) that the outer main gimbal would be in constant motion for all exercises except something which remained locked in one position. It must do.
If we are to imagine that the pod in mid field view has a window of , say 1 deg. ( I think someone, possibly Mick, has stated the deg field of view for this atflir, but let’s imagine 1 deg.
The pod aims at that space in sky and then inner finer gimballed mirrors , which require minute movements within that window to track an object, take over.
These finer mirrors must be pointed at the correct part of sky to track, they are bound by the field of view.
In the gimbal footage the object tracks from 54 deg left and couple deg below, right across the nose. This is a massive amount of sky that it passes through which would require the gimbal to rotate very slow and steady constantly whilst the internal mirrors keep track within that field of view.
Mick, or anyone else can test this if they have a gimballed device, like the flir in Micks videos.
1) Attach device to chest ( or any motion less object ) with its base against chest so pointing out like an atflir.
2) Stick a laser pen on front lense to denote it’s line of sight.
3) Moving the pod using it’s bound 2 axis of rotate and pivot- track an imaginary line across a wall 54 deg left and a few deg below horizon.
It becomes immediately obvious that the pod must be constantly finely rotated with slight pitching all the way. Once it gets to centre, rather than a flipping of the pod, it merely must continue the rotation but apply an opposite, mirrored pivot to follow it the other side. It cannot do any other combination of movement and remain on track, it is bound to this motion if it wishes to remain on target path. It’s also the easiest position to remain in against a target trying its best to evade. The on board algorithm would be designed so as to remain at certain angles at any given time whilst tracking an object - dependent on its current trajectory.
I believe that the 0 deg point of gimbal lock ( described as an undesirable state by Raytheon ) is not a set position in front of plane but a point in relation to trajectory of object which lies directly along its pivot axis.
If it allowed an object to track straight along this line whilst only pivoting, it could lose lock easiest if object suddenly banked. The pivot point would always be at , say 45 deg from the line of predicted trajectory so that any sudden change could easily be countered by slight rotation.
I will try and do some drawings to explain this better but if we imagine an object tracks straight and level left to right. If the pod followed it by having the pod merely pivot in line with object without any required rotation- this could lead to sudden loss of track if the object suddenly moved up or down. The pod would have to rotate a larger amount and pivot to regain. Whereas if it remained at 45 ish deg, any sudden change is covered by slight rotation. It has its bases covered so to speak.
Very difficult to explain so apologies if not clear. Will try and do a brief drawing when I have time to better explain my thought.
 
I looked at an article about a comparison of the Mig-29 vs the F/A 18 the other day, and it said that the Mig-29 had an advantage because it could fire its missiles at other fighters while the targets were 90° off to the side, and the F/A 18 could not. So your implied reasoning of "if it can't target 360°, it's not suitable for dogfighting" seems flawed to me.

What we're really trying to answer is how close and how agile of a target the ATFLIR has been designed to be able to track (after it has been established that ATFLIR was designed partially for air-to-air); but I'm a bit at a loss to see why this is important for the topic at hand, maybe someone can remind me?
Your understanding of how AA missiles are targeted and launched and guided is not possibly accurate, the ATFLIR is not used to guide them to targets. They have their own targeting, the Sidewinder (AIM9x) is IR guided by it's own guidance IR detector. Other missiles use RADAR.
 
Also we have seen video, which Mick has described in recent podcasts where the on board system flashes a gimbal lock warning up on screen. It’s seen as possibly significant in the context of gimballed pods not being able to track and sudden rotation required to rectify. I don’t believe this is the case. I don’t think they would have an explicit on screen warning to tell the pilot that the camera is gimabal locked and in need of rotation. I believe this is a flight path warning, similar to a low altitude warning. It’s warning that the jet itself is approaching a gimbal locked position where one of its axis of movement will become redundant. This is probably only seen when attacking ground targets. Swooping in with extreme movements. This is from Wikipedia gimbal lock page -
“Consider a case of a level-sensing platform on an aircraft flying due north with its three gimbal axes mutually perpendicular (i.e., roll, pitch and yawangles each zero). If the aircraft pitches up 90 degrees, the aircraft and platform's yaw axis gimbal becomes parallel to the roll axis gimbal, and changes about yaw can no longer be compensated for.”
 
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