There are many technical problems with Flyer I 1903. The plane was unstable, underpowered and had propellers that appeared only in 1908, exactly in the same year when the Wright brothers flew for the first time in front of credible witnesses. The brothers simply lied about their flights in 1903-1905. They built their planes in France in 1908 with french engines (Barriquand et Marre), french propellers and using the entire French flight experience of 1908.
see:
http://wright-brothers.wikidot.com