I only started in 2005 so can't really comment on 1993 but my sense is that the rate of change on the GA scene is relatively slow.
20 years into the future I think a lot of the current trends we see today will have accelerated. Legacy group A aircraft will gradually fade from existence, and the three axis microlight will become even more prevalent than it already is.
However subject to economic improvement I there may be some expansion in the more serious owner and charter operated SET. The recent granting of a SET AOC in France suggests that in the future TBMs/PC12s etc may enter the public charter business for the first time Europe. So perhaps a bit of a polarisation in fact between the 'top' and 'bottom' of the scene in terms of complexity and cost of the aircraft themselves.
The regulatory burden has become almost unbearable now but I am actually hopeful that this might swing back and that there are signs finally that the CAA and EASA might see another way. Hopefully in 20 years time we will have more cheaper and potentially non-certified equipment to enable aircraft to carry traffic avoidance and altitude reporting for whom it is currently too expensive. This would make the issue of airspace and TMZs less contentious. I suspect VHF will still be the primary way of communicating.
GPS approaches will be allowed without ATC cover in the UK and hopefully aircraft without a full CoA will be allowed to fly IFR with certain conditions attached (for example the Vulcan is now allowed to despite having a Permit to Fly) enabling the utility value of light aircraft to increase and more interest in doing an instrument qualifications as a result.
I doubt it will have happened by 2033 but eventually, in the longer term, JET A1 burning diesel engines will replace avgas burners in most new aircraft. The advantages of having a common fuel with jet and turboprop aircraft are obvious as well as the lower cost of the fuel itself.
Last edited by Contacttower; 22nd Oct 2013 at 16:48.