How it was done just a few years ago. Bird plane was for snooping on wildlife crime and clandestine work in rural areas. Big one carried a Pentax 645 (120 size film) It was a powered glider, 400 still shots on 6cm movie film stock. Motorway and construction progress shots mostly. Corgaff Castle was taken just after a snow storm and full-size aircraft couldn't take off till runways were cleared. All the models were hand launched and belly landers, no wheels , rough terrain on average. Golf course fairways were heaven ! Cameras were 35mm Canon, Pentax and Nikon. Advertising on aircraft proved to be a mistake hence the "Bird Research" motif . The guy with the shotgun under his arm always gave the clue " I suppose it`ll be these damned geese/buzzards/crows" The usual knowing nod, wink and bit of " I`m not at liberty to say" got me out of a lot potential trouble.