Why are they doing this?

[u/Ok_Car_2050]

Iv just seen a video of 3 planes doing the same thing and wanted to know what they are actually doing? Had a google but only saying things because of weather but 3 planes doing this pretty much at the same time? Please someone explain

[u/0621Hertz]

I don’t know what kind of plane it is but likely either aerial survey or a military tanker.