Here is your revised Hype project which I now call: GlobalAviation_JHSv1.hype.zip (1.7 MB)
There were numerous errors in setting keyframes and a “Timeline Action” issue. I won’t be fully writing them out but please see “Notes” below. In general You were working against yourself with different settings being in conflict such as keyframes for the same property being stacked on each other.
The main point with the attached Demo is to show You the animation can work - so I stripped things out that I thought were problems and re-animated the plane & clouds. Some of my settings may not be your final intention - but again the plane and clouds do work, so You have a place to begin making adjustments.
I did not see the value of having (2) sets of clouds so, for the “Back” clouds only, I used just one and re-synced the animation. I did not change the others in case there was some purpose I could not discern for the duplicates. Easy enough to re-create the second copy of “Back Clouds”.
There were conflicting key frames with the original “Back” clouds that were not present in the “Middle Clouds”.
Also - I changed all relative timelines to “standard” ones. There wasn’t necessarily a problem per se but I wanted to eliminate as many variables as possible in working on your project.
And here was your “plane issue” - I removed this Timeline action…