hybrid contrails

Army Chief of Staff Gen. Mark Milley was the keynote speaker at Norwich University during its Reserve Officer Training Corps Centennial Symposium, Northfield, Vermont, on April 21, 2016. During his speech he talked about "little green men and hybrid armies" [at 34m40s] This refers to forms of...

This is a follow up to the thread https://www.metabunk.org/threads/squiggly-sinusoidal-thin-contrails-over-europe.3194/ that I think merits its own thread. In the above thread there are seven in total different occurrences of these highly unusual contrails captured on photo or video. I have...