I'm not sure these chaps are likely to help your essay much, nor probably can I. But, do a library search on recent conferences by both the RAeS and the AIAA - it's been a hot topic over the last couple of years and there are a lot of papers that should help you.
However, a few thoughts that I've picked up around the Bazaars...
Big issues are in general...
- Availability of spares
- Integrity of old spares
- Suitability of modern fuels and lubricants
- Lack of sim availability for crew currency and conversion training to modern standards
- Handling qualities not always being to modern standard either
- Manufacturing / maintenance techniques used with which modern crews are often unfamiliar
- Lack of current manufacturer support when you hit a snag.
Overall, if these and a few other problems are solved, and the aircraft are operated within the envelope for which they were designed, safety should be pretty much equivalent to modern types. In general operating costs will be much higher due primarily to fuel consumption and maintenance man-hours, but investment value much lower. So older aircraft, even pre-WW2 on occasion, can be a good commercial investment if an operator needs the asset but is planning to fly very few hours.
One other thing, a lot of the remaining fleets, and thus sources of parts of older types exist on the registers of "less respectable countries". This can cause severe paperwork problems as "first world" aviation authorities such as UK-CAA or FAA are rather disinclined to accept parts-release paperwork from such countries. A classic example of this is UK based Piper Pawnees, for which spares are readily available - from Argentina, not the UK government's favourite country at the best of times. So, you can buy all the spares you want, but UK-CAA won't let you use them.
Hope this helps a bit, but you might find it helps to post Engineering questions in "Engineers and Technicians", rather than here or certainly "Rumours and News". (Hint for new players, post once and in the right forum or you lose friends quite quickly.) These folks are giving "pilot answers" which are probably of limited relevance to an Engineering report.
Best of luck,
G
Last edited by Genghis the Engineer; 6th Nov 2003 at 05:41.