Steady on, Oz. I said 500 or 1000 years. Not 2000. Although the thought experiment could be set at anytime. Copper age, anyone? We could invoke a BN2A then!
Bre901, that's the point: How does the technology of the era limit what could be done, and how to work around those limitations.
For example, I think a reasonably competent hanglider is feasable using bamboo + silk cloth. Ditto parasails & conventional gliders. Not sure that 500 or 1000 years ago that plywood was available?
Power is a very difficult one. Steam thrust was demonstrated in ancient Greek times. Perhaps some sort of steam engine is feasable with available metalurgy.