Having watched the video of the Chinook, one of those random questions just popped into mind.
Seeing it drop 6 individual bags of aggregate at a time, very carefully and precisely, would it be quicker and/or cheaper to do it with say 6 Jetrangers or 350s (other types are available!), going round and round in a circuit taking one bag each at a time? I’m thinking of the high speed commercial lifting operations that you see with Christmas trees/rocks for dry stone walls, that sort of thing.
I have no idea how much a Chinook or a Jetranger costs, how much those bags weigh or if they could even be lifted by such aircraft.
And definitely no criticism at all of the job the Chinny is doing, just idle meanderings of the mind while walking the dog.