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@Edward Current if you happen to check how sensitive is the final parallax motion-stop to the F18 exact ending trajectory, the unknown plane direction, and both combined, this would be interesting to see.

Ok, sorry for misinterpreting the cue dot then. You're way better than me, and most of us I'm sure, at seeing things in 3D. I still think this almost-complete slowdown of parallax motion is quite a coincidence, cue dot Az or not. If you guys are confident that your trajectory is plausible, go...

Am I wrong in thinking that if the plane is banked and look straight at a non-moving object (or exactly aligned moving object), the cloud parallax will stop at 0 cue dot Az, not at 0 horizon Az ? Like you say, at 0Az cue dot, if you push the nose down you go towards the target. To me it's more...

The cue dot tells us that when the object is right in front of the pod, the background motion is at its minimum. This is not the case in your schematic above. The directions need to be perfectly aligned, not simply parallel. I'll give you that, I don't know much about aviation. Do you mean that...

In that configuration the pod head azimuth would not be 0 like in the vid (0 azimuth for the cue dot, which is more representative of the object alignment of the pod head because this is in the plane reference). It would be a small angle to the right.

This represents hardly 0.1 FOV/second. Which means close to perfect alignment as I show above. That a scenario takes too much happy accidents to happen reduces its credibility. In the distant plane scenario, you need : - an unidentified plane, in an area of US military exercises - an...

Thanks for your reply @Mendel . Not sure you understand what I mean though. Getting roughly aligned with the object direction is different than being almost perfectly aligned. For the cloud motion parallax to stop as it does, the F18 has to be in close-to-perfect alignment with the object. Here...

A question that bugs me : what is the probability for a plane at 25000 ft, 350 Knots, to make a coordinated turn and end up in the exact boresight of another plane at 19000ft, 380 Knots, so that the cloud motion parallax is close to 0 ? In other words, @Edward Current , is the cloud motion...

Edwards Cool, not too far then. Yes you're right about the FOV. That's to consider that the clouds are perfectly flat though. All things considered I don't think the close trajectory having to climb makes a big difference, it's a trajectory that stops mid-air anyway, so it's already out of the...

Based on these 3D line of sights, a leveled trajectory at 30Nm means the distant plane would have had covered 3.3Nm in 30s. That's a speed of ~400 knots, faster than the F18. Is that consistent with what you find @Edward Current ? It's much easier to this these things directly in the 3D model...

@Edward Current I don't think we can conclude on the object having to change altitude in the close (before LoS) scenario. I did a quick schematic with Geogebra 3D, based on these positions for Gimbal at PT1 (0'01) and PT4 (0'31). I choose this one because in this scenario the size of the...

Thanks a lot, that's great. Don't you think any horizontal trajectory before the LoS will have a corresponding steady trajectory (or more), further away ? The vertical movement the object would need in the close scenario is new information.

@Edward Current , looks like great work. I think what would add a very valuable contribution to the discussion is whether your 3D model can retrieve what we see in the video, but with an object's trajectory as seen by the pilots : 10Nm or less, before LoS intersection, stops mid-air. If you...

Not sure about this. By comparing the vertical angle given by the cue dot on the display, with the same vertical angle in your simulator, it helps refining the AoA. Just eyeballing, the AoA needs to increase along the course of the video for the cue dot "offsets" to match. Which would be...

@Mick West , I got that, I'm talking about the vertical displacement of the cue dot. The moment when the blue circle and white circle interesect (wing plane, elevation plane). This is the moment when the cue should indicate 0 vertical offset. Because its upper bound is 0, it just moves...

To be perfectly clear, the moment when the cue dot is up the screen should correspond to when the blue arrow (cue dot) goes above the -2deg elevation plane ? Because it seems to suggest even higher AoA than 5, it matches better with AoA=8. But there is also elevation that plays into it of...

@Mick West , that's great ! That explains why the cue dot is much more negative than the elevation, then becomes positive. So this cue dot is giving helpful information after all. And it helps to refine the constraint for the AoA !

At least I recognize when I don't know something. This was simply a question, you seem to be more of an expert on the ATFLIR display, I'm not. Now I think I bring something to the table on reconstructing the trajectory. It's not because you don't like where this is going that you have to attack...

A video to compare the elevation given by the cue dot, to the pod elevation bearing on the screen. If we consider that the top vertical extent of the dot is 0deg, and the middle of the screen (reticle) is -90deg, the ruler gives us the vertical angle given by the dot. They are both consistent...

Possibly silly question, but are we even sure the pod is in A/A mode ? GoFast happened 10 minutes before. Could it be that they set the pod to A/G mode during GoFast, because they were essentially tracking an object, if not close to the surface, well below the plane. And left it that way during...