A few comments I would like to throw into this interesting discussion.
- The Wright brothers chose Kitty Hawk for its strong, steady winds.
- The Wright Flier probably did not need to accelerate along the rail. In the 27mph winds of 17 December 1903 it may well have been developing sufficient lift to get airborne when static, due to the head wind. The thrust of the propellers was simply needed to maintain its position over the ground and prevent it getting blown backwards. (The ground speed of the first flight was 6.8mph)
- By starting with such a strong head wind, the engine only had to sustain flight, which as many will know, takes a lot less power than a take off does. A simple analogy is the difference between sustainer ('turbo') engines on gliders and those on the self launchers of the same model which are typically 3 to 4 times the power.
- The Wrights had been practicing with their gliders for four years. No wonder modern day pilots struggle with the twitchiness of replicas of the Flier. Unicycles and 1970s model helicopters both take hours of practice to master but can be operated once the knack is acquired.
- The rail gave the Wrights a level, consistent take off surface. Soft sand is never an easy runway for take offs, but is a fairly forgiving surface for less than perfect arrivals.
- Hoffman Field did not have Kitty Hawk's reliable headwinds. The descending weight catapult gave the closest equivalent.
- The first flight started a considerable distance from the hill. The ground there is virtually flat. See http://ferrytrails.********.co.uk/2012/11/kitty-hawk.html (replace the stars with blog spot (no space)) (Note an error in the text of the link above. Its states the last flight of the day was 59 minutes. As we all know, it was 59 seconds).
I have been to Kitty Hawk and would strongly recommend 'believers' and 'non-believers' do too.