re: #94 LudwigVanQuixote

Seriously, try it! Do the experiment. Take a straight wire or a pen or something long and thin and move it around . See if there is any place you can put your head where that straight horizontal thing looks curved and vertical.

Wind patterns move the comtrail, also the plane could be making a turn. It’s a mistake to think the trail is straight. It’s most likely an optical illusion.