In 1969 Bill Gates asked: "Who would ever need more that 250 Kb of memory?"
In 2008 even your mobile phone has at least 50 times that memory.
Aviation technology will change very dramatically in the not too distant future. I would not discard supersonic and hypersonic flight too quickly. Indeed, it is probably inevitable within this lifetime.
(From one old enough to recall traveling in state of the airline art DC3's, Connies, Short flying boats, the first turbine Viscounts and F-27's and excitement of the first "propless" B707s!!)
Tail Wheel