Thanks for your replies.
I have tried all of those techniques, they will indeed change the "eye alt", as long as I am not trying to view directly from the side of the flight path. What I am trying to do is to view the plane icon from the side, in the same horizontal plane as the track, where the performance of the controls during a 180 degree roll is evident.
Here is what happens in Google Earth:
I adjust the tilt of the view so that I am looking parallel to the earth surface. At that point I would like to "climb up" to the flight track to look at it, but no matter what I do, as long as the earth surface is horizontal, the eye altitude is locked to the earth surface.
I can change the eye altitude through a combination of mouse operations, but only if I change the tilt first. But then when I change the tilt back to get a look from the side of the track in the same horizontal plane, the eye altitude changes in a way that I cannot predict, and I wind up being either too high or too low to get a close up view of the track.
With everything that I have tried I either cannot get very close to the track, or I cannot get in the same horizontal plane, I have to look either up or down.
So, here is what I would like to do:
1. Set the tilt so that I am looking parallel to the earth surface.
2. Adjust the eye altitude until it is equal to the altitude of the track.
I looked on line, this apparently is a common question with multiple replies on how to do it, none of which work for me. Most of them are hacks of one sort or another.
Best regards,
Bill