Be aware that contrails are different as opposed to grayish "vapor trails" sometimes observed when flying reduced with flaps extended. They are formed of liquid h2o within the immediate decompression and cooling of air higher than the wings. RDoug: I found precisely the same thing straight away — The "M", https://70mhz-frequenzausgang13332.getblogs.net/70136464/detailed-notes-on-haarp-wettermanipulation