>https://globe.adsbexchange.com/?icao=ae4f15
Depends on what you are asking about… dozens a day cross the pond for a variety of European destination for a myriad of reasons/missions.
Or are you referring to the flight path markings?
Which could be the result of intentional radar / gps signal jamming or the fact that it is transponding MILAT and you are on a site specific to adsb.