In 30 years I see VTOL technology being utilized in transport aircraft to minimize the space needed for air travel. As cities increase in size and real estate becomes harder and harder to secure in great enough numbers for the amount of air traffic that we will see in the future, traditional airports will decrease and we will see more heliport style air stations.

I'm not saying traditional airports wont exist, and there will still be plenty of air carriers flying the aircraft of today. But regional companies and air taxis, etc. will be utilizing more helicopters and VTOL aircraft than before.

I see a revamp in airspace and airways and a decrease in VFR operations (general aviation traffic). The new airspace will better accomidate IFR traffic and will help deal with the congestion that we get today.

New aircraft will be more efficient and probably will cruise higher and faster than today's designs. Cockpits will stay relatively the same, probably more use of HUDs and FLIR. Navigation technology will increase tremendously.

Piston aircraft will be a thing of the past, and alternative fueled turbines will probably be the new thing. I don't see there being a huge private plane industry but it will still exist. Simulators will be way better than they are today and will take the place of training in light planes (when getting a commercial ticket). Training will also be aircraft type specific.

Aircraft safety will be the biggest innovation I think, more and more emphasis will be put on traffic avoidance and systems will become more and more reliable. Better seats and restraints will be put into aircraft, as well as things such as airbags in airliners. Ultimately the future of flying is more efficiency, safety, and less environmental impact.