The path to green flight is paved with money. In our transactional world, good ideas are sometimes rewarded with filthy lucre, even if those ideas are intended to clean up a besmirched world. Several examples of clean aviation attracting solid investments follow, along with some stumbling on unexpected obstacles. Jetson ONE For a flying machine lighter than most of its prospective pilots, the Jetson ONE has attracted a host of followers, including the host of a late-night chat show. Besides receiving 3,000 purchase requests in two months the firm has sold its initial production runs for 2022 and 2023. At $92,000 a unit, 100 craft in the first year would net $9.2 million, enough to finance the simple assembly …