There’s a lot of that going on at the moment. I’ve seen a few observation aircraft doing similar things. Possibly mapping or so sort of air quality monitor. I’m not sure. What is really striking is the amount of air freight. I had no awareness of just how many freighter operators there are and how many flights.
Noted the cargo flights also Ben. I've seen an increase in cargo flights from China into Stansted of late. Or it could be that the lack of passenger flights is highlighting the cargo stuff.
Living under the approach to Newcastle I make a dash for the window on the very rare occasion I hear something actually coming in at the moment, which is hardly anything. Saw an unusual Learjet on approach a couple of days ago with massive tip tanks. Didn't show up on Flight Radar so couldn't identify. Also the angle of the sun made any markings impossible to make out.
Downloaded the UK danger areas, the top set of runs looks as if its Area 5 & the lower one Area 8. Both of these are designated Air to Air refuelling areas. Google eg_enr_6_5_1_1_en.pdf to get the map.
Planefinder looks interesting, will have to try it on another day when military are airborne, 'cos today it showed a RAF 146.
Keith