This the final slide of note from the presentation featured prior. The vessel on the left looks, and is, rather silly ~ Airbus hoping that Flettner rotors will deflect us from the fact that carbon emissions due airliners continue to rise near-exponentially. More to the point the same report points out that almost all reductions in emissions are due advances in jet engines, whilst the most ubiquitous aircraft in the form of the Boeing 737 dates from a time now nearer to that of the Wright Brothers than our own.
Altogether more worthy of worthy of our attention is the re-discovery of surface-effect craft in the form of Regent's efforts in the US. Note in particular that it relies solely on aero-propellers instead of water-screws: something I think we need to get used to if we want drones to move faster and more efficiently over water.
Conventionally what stymied these aircraft was fairly lousy sea-keeping, which meant that they would as often as not come to grief when seas got choppier; which they've a nasty habit of doing.
