Further update:
For clarification, the problem is invoked by pressing the “insert” key to switch to “showcase” camera (I’m using MSFS 2020 keyboard profile.
Viewing aircraft exterior shows sea and sky when overland returns when the sim next started.
The wake turbulence issue has not returned.
Selecting the showcase camera on the menu bar only needs to be done once to fix it. However the problem will return at the next sim start.
Further update:
Wake turbulence issue is resolved. The Aerodynamic Visualization (CFD) setting (under Flight Interface menu) had become enabled after the SU3 beta update. On first boot, the sim was showing the CFD, which can easily be mistaken as wake turbulence. So the solution is to uncheck the CFD option.
I am still investigating the “showcase” camera view of only showing sea and sky. This occurs over land or sea.
I tested this a few times earlier. One the first spawn in, I got the sea, and water thing. The sim later crashed. On the second launch viewing the drone camera view worked as expected. It seems entirely random whether it works or not. I originally thought that activating the External camera via the top menu at least once would enable the keyboard shortcut to work, but that doesn’t appear to be the case, and it may randomly work anyway. I never saw this until last night.