It'll be planes, because the running cost per mile travelled is critical to making the whole thing cost effective.
Power consumption and weight of the rig isn't insubstantial, so the smallest planes and gliders can't be used, and after that cost per hour and cost per mile are the key metrics.
Power consumption and weight of the rig isn't insubstantial, so the smallest planes and gliders can't be used, and after that cost per hour and cost per mile are the key metrics.
Planes can be 10x cheaper by that metric.