Contrails look like brilliant white comets high in the sky, at an altitude of over 30,000 feet in cold, dry air. At that height, even a large airliner is barely visible. Contrails appear some distance behind the airplane where the hot exhaust and cold air mix. The air pressure up there is so low that the ice crystals sublime directly back into invisible water vapor in a minute or so. Contrails disappear completely, leaving clear blue sky.
Chemtrails appear at lower altitudes, often low enough to identify the model of aircraft with the naked eye. The number of streaks emerging directly behind the aircraft often does not correlate with the number of engines. Chemtrails form long clouds that can stretch from horizon to horizon. Chemtrails spread out into a milky haze that covers the whole sky. Chemtrails do not disappear like Contrails because they are a solid aerosol.
Transcontinental airliners fly along fixed paths, going both directions at different altitudes, another plane coming along every few minutes. You may have looked out the window on one of your travels to see another airliner come zipping by, separated by only a couple thousand feet in altitude. Have you every noticed one of these passing jets leaving behind a lasting Chemtrail? If that were the case, then visibility along these flight paths would soon be reduced to zero. Every flight would be forced to fly by a different path.
Have you wondered what has happened to the bright blue sky we used to enjoy all summer long? Go outside and look for yourself.