Where I see future potential is in small turbines.
As Peter said, very doubtful. R&D costs, certification costs, basic thermodynamics and a shrinking GA market makes this a long shot.
Also turbines are a totally different class of airplanes. You have to fly them like an airliner. For 150hr/year of recreational flying, they're a pipe dream.
Incidentally, all these speculative turbine-envy lifestyle discussions somehow always seems to end up at the JetPROP/Meridian, even though it's a noisy 70s design w/the range of a Cirrus...(cuz' it's the only turbine we could conceivably afford
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The AIR BP booklet shows avgas available in some suprising places
Ah, yes. Ever actually tried arranging for avgas in some of these surprising places? Either the booklet info turns to be out of date, the actual supply turns to be unavailable when you actually need it, or you need to preposition the drums a month in advance, at exorbitant costs.
Avgas *is* more or less available all around World. The problem is flexibility. You're simply excluded from a large number of airports which don't, and exposed to availability issues at those that do. Even in Europe you have to plan your routings carefully to account for availability.
Finally, I hate to bring up environmental concerns, but in this day & age fuel efficiency counts, and I don't see a bright future for 28gph twin piston avgas guzzlers... - btw, I really like the Tecnam P2006T concept w/Rotax mogas, but at 600nm range & 135 kts cruise, the specs are less than ideal.
(edit: Sure would be nice with a TBM though - I know we don't "need" it per se, but still...
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