There was some concern (not by me) that I needed to hold the 26 lb panels down when traveling. My roof is unusual with the raised side rails and the front and back caps are higher than the roof. I have added a 2"X 8" triangle in front of the first panel to keep air out although that far forward it's probably in a low pressure area...no lift and protected from the 70 mph winds.
There is also a 1" opening at the top and bottom of the panels so doubt there is enough pressure under the panels to lift them up. I'll put some small pieces of paper under the bottom of the supports and if they do not blow out from under...no problem and no cord needed.
I already knew the aerodynamic of a brick but here is a good wind tunnel test of a bus. Little or no wind at the roof on the front half of the bus. The turbulence at the back concerns me some although my roof is unusual with raised areas at the front and back so not sure if there will be any turbulence at the sunken roof level at the back.
https://m.youtube.com/watch?v=_NPNiyR5cWo
For those worried about the panels lifting up, I decided to run a cord from the 2x8 triangle to Eye bolts under the panels and a cord to the roof for every 2 panels to hold them down. Also added 2 more fixed panels for a total of 900W.
