It's all about the Math - with an assist to the Thunderbirds

Back in the day, math in high school wasn't much fun.  I missed the slide rule era by a few minutes.  I was on the front end of electronic calculators so much so that the education system was afraid to let me use them.  And no way would anyone try to teach me how to use them.  I'll guess my teachers at the time didn't know how they worked.
There is a point to this.  
The point is trying to define if some photos are the skill of the photographer - or just lucky.  In my case, let's work on the luck factor.

Close Pass

NIKON D500 Ver.1.15/70.0-300.0 mm f/4.5-5.6

450 mm, 1/2500 sec, f/5.6, ISO 180 (Auto)

MANUAL mode, Size DX

Two things.
Photographically this won't win any awards.  Way too far away that even 450 mm couldn't help it.  Needed aggressive crop.  Looks good on small media.  Not so much on the monitors.  I used a specialty sharpening package to help out.  But not enough detail int he aircraft for me.
Now to the physics.  
Given items.  The F16 is 49.5 feet in length.  Speed of sound is approx 770 MPH standard day sea level.  One mile is 5280 feet.  Thunderbirds, or Blue Angles, are not allowed to exceed the speed of sound for air show purposes.  For the sake of this discussion, lets say that each opposing aircraft are traveling at 500 MPH, on the very conservative side.  The closing speed would be 1,000 MPH.
Now the fun stuff.
My methodology for this type of picture is to follow one aircraft and at a point where I think the cross will occur, press and pray.
At a closing speed of 1,000 MPH, the aircraft are getting closer at 1467 feet per second.  About the speed of a 9mm round.  To take this a step further, the D500 will shoot at 10 frames per second.  Simple math, what I do best, would say that the aircraft will travel 147 feet per second,  roughly three time the length of the aircraft.  It is very possible, I'd say even probable, that the opposing aircraft would not be in the photo.  Opposing aircraft shots are not easy.  You could possibly guess where the cross will occur and focus there.  And hit the shutter when you see the aircraft.  You will of course miss the shot.  
The opposing aircraft that was traveling at 500 MPH is now traveling at 1,000 MPH.  And if your panning is perfect so you catch one aircraft in focus, the opposing aircraft has moved, in this case, over seven inches.  
I tried to catch a cross of two prop aircraft.  Let's say they crossed at 600 MPH and I had to use a shutter speed of 1/250 to catch the prop blur.  The opposing aircraft would have covered a little over 50 inches during the shutter actuation.  it didn't work for me.  The software help isn't that good.  In this case, it would have been better to guess the point, press and hope for the best.
So much for perfect focus.  
In my case, this is all luck.  And a lot of software work.